Wednesday, December 21, 2011

Myths and Truths of Obesity and Pregnancy


Vitamins, Weight Gain, Preterm Birth and More

Ironically, despite excessive caloric intake, many obese women are deficient in vitamins vital to a healthy pregnancy. This and other startling statistics abound when obesity and pregnancy collide. Together, they present a unique set of challenges that women and their doctors must tackle in order to achieve the best possible outcome for mom and baby.

In the December issue of the journal Seminars in Perinatology, maternal fetal medicine expert Loralei L. Thornburg, M.D., reviews many of the pregnancy-related changes and obstacles obese women may face before giving birth. The following myths and truths highlight some expected and some surprising issues to take into account before, during and after pregnancy.

“I treat obese patients all the time, and while everything may not go exactly as they’d planned, they can have healthy pregnancies,” said Thornburg, who specializes in the care of high-risk pregnancies and conducts research on obesity and pregnancy. “While you can have a successful pregnancy at any size, women need to understand the challenges that their weight will create and be a partner in their own care; they need to talk with their doctors about the best way to optimize their health and the health of their baby.”

Myth or Truth?

Many obese women are vitamin deficient.


Forty percent are deficient in iron, 24 percent in folic acid and 4 percent in B12. This is a concern because certain vitamins, like folic acid, are very important before conception, lowering the risk of cardiac problems and spinal defects in newborns. Other vitamins, such as calcium and iron, are needed throughout pregnancy to help babies grow.

Thornburg says vitamin deficiency has to do with the quality of the diet, not the quantity. Obese women tend to stray away from fortified cereals, fruits and vegetables, and eat more processed foods that are high in calories but low in nutritional value.

“Just like everybody else, women considering pregnancy or currently pregnant should get a healthy mix of fruits and vegetables, lean proteins and good quality carbohydrates. Unfortunately, these are not the foods people lean towards when they overeat,” noted Thornburg. “Women also need to be sure they are taking vitamins containing folic acid before and during pregnancy.”

Obese patients need to gain at least 15 pounds during pregnancy.


In 2009, the Institute of Medicine revised its recommendations for gestational weight gain for obese women from “at least 15 pounds” to “11-20 pounds.” According to past research, obese women with excessive weight gain during pregnancy have a very high risk of complications, including indicated preterm birth, cesarean delivery, failed labor induction, large-for-gestational-age infants and infants with low blood sugar.

If a woman starts her pregnancy overweight or obese, not gaining a lot of weight can actually improve the likelihood of a healthy pregnancy, Thornburg points out. Talking with your doctor about appropriate weight gain for your pregnancy is key, she says.

The risk of spontaneous preterm birth is higher in obese than non-obese women.


Obese women have a greater likelihood of indicated preterm birth – early delivery for a medical reason, such as maternal diabetes or high blood pressure. But, paradoxically, the risk of spontaneous preterm birth – when a woman goes into labor for an unknown reason – is actually 20 percent lower in obese than non-obese women. There is no established explanation for why this is the case, but Thornburg says current thinking suggests that this is probably related to hormone changes in obese women that may decrease the risk of spontaneous preterm birth.

Respiratory disease in obesity – including asthma and obstructive sleep apnea – increases the risk for non-pulmonary pregnancy complications, such as cesarean delivery and preeclampsia (high blood pressure).


Obese women have increased rates of respiratory complications, and up to 30 percent experience an exacerbation of their asthma during pregnancy, a risk almost one-and-a-half times more than non-obese women. According to Thornburg, respiratory complications represent just one piece of the puzzle that adds to poor health in obesity, which increases the likelihood of problems in pregnancy. She stresses the importance of getting asthma and any other respiratory conditions under control before getting pregnant.

Breastfeeding rates are high among obese women.


Breastfeeding rates are poor among obese women, with only 80 percent initiating and less than 50 percent continuing beyond six months, even though it is associated with less postpartum weight retention and should be encouraged as it benefits the health of mom and baby.

Thornburg acknowledges that it can be challenging for obese women to breast feed. It often takes longer for their milk to come in and they can have lower production (breast size has nothing to do with the amount of milk produced). Indicated preterm birth can result in prolonged separations of mom and baby as infants are admitted to the neonatal intensive care unit or NICU. This, coupled with the higher rate of maternal complications and cesarean delivery – up to 50 percent in some studies – in obese women, can make it harder to successfully breast feed.

“Because of these challenges, mothers need to be educated, motivated and work with their doctors, nurses and lactation professionals to give breast feeding their best shot. Even if you can only do partial breastfeeding, that is still better than no breastfeeding at all,” said Thornburg.

Thursday, December 15, 2011

Majority take prescription drugs during pregnancy


Almost two-thirds of women in British Columbia filled at least one prescription at some point in their pregnancy, including drugs with potential risks, according to a new study by University of British Columbia researchers.

The study, published online today in the journal Clinical Therapeutics, is the first of its kind in Canada. Researchers analyzed population-based outpatient prescription claims data for patterns of prescription drug use during pregnancy in B.C. from 2001 to 2006.

The researchers found that 63.5 per cent of pregnant women in B.C. filled at least one prescription. One in thirteen – or 7.8 per cent – filled a prescription for a medicine known to be risky in pregnancy – most often for select medicines for anxiety, insomnia and depression. Drugs that are strictly contraindicated pregnancy, however, were filled in less than 0.5% of pregnancies.

“Although much remains to be understood about the appropriateness of medicine use that actually occurs among pregnant women in B.C., one encouraging finding from our study is that existing use of medicines with known risks declines dramatically when women become pregnant,” says co-author Steve Morgan, an associate professor in the School of Population and Public Health (SPPH) and Associate Director of the Centre for Health Services and Policy Research (CHSPR).

On average, pregnant women filled 2.6 different types of drugs, while 15 per cent used five or more prescription medications during their pregnancy. Prescriptions most frequently filled during pregnancy were for antibiotics (30.5 per cent), respiratory drugs (25.7 per cent), dermatologics (13.4 per cent), and drugs that act on the nervous system (12.8 per cent).

Other study findings include:

- The use of medicines in pregnancy slightly increased over time, going from 63 per cent of women in 2001 to 66 per cent in 2006.
- Women aged 20 years or younger were most likely to take prescription drugs during pregnancy (69 per cent) while the lowest rate occurred among those aged 30 to 35 years (62 per cent).
- Prescription medication use was also high in the first three months immediately following delivery, a period when women may be breastfeeding, with 61.3 per cent of women filling prescriptions.

“Since pregnant women are normally excluded from clinical trials of new drugs and post-market study is limited, there is little evidence on the risks and benefits of many of the most commonly used drugs in pregnancy,” says lead author Jamie Daw, a researcher at CHSPR, part of SPPH. “Given the prevalence of prescription drug use, more research is needed to help pregnant women and their physicians make informed decisions.”

Wednesday, December 14, 2011

Cold Medications in Pregnancy


Experts in pregnancy and breastfeeding health at the California Teratogen Information Service (CTIS) Pregnancy Health Information Line warn expectant moms about the potential dangers of common cold medicines during pregnancy. CTIS is a California non-profit housed at the University of California, San Diego that educates the public about exposures during pregnancy and breastfeeding.

"Every year around this time, we get a significant number of calls from pregnant and breastfeeding women in California who are battling colds and are worried about which meds they can and can't take," said Christina Chambers, PhD, MPH, professor of pediatrics at UC San Diego and CTIS program director.

"The callers I’ve personally spoken to have valid concerns because there are certain ingredients in over-the-counter medications they need to watch out for that could be harmful to their developing babies," explained Sonia Alvarado, CTIS supervising counselor who takes calls through the service’s toll-free hotline and online chat service. As a result of the potential for harm, Dr. Chambers and Alvarado have compiled a list of helpful tips for moms and moms-to-be battling colds this holiday season.

Top Five Cold Remedy Tips During Pregnancy:

1. Less is More. Remember that “less is more," or rather, less is more recommendable when it comes to treating colds during pregnancy. Take only those medications that are needed for your specific symptoms. Many cold remedies have three to six ingredients, some of which you (and your developing baby) do not need. If your major complaint is a cough, for example, then avoid a combination drug that includes a nasal decongestant, an extra medication you can do without.

2. Oral Decongestion Alternatives. While the majority of studies looking at oral decongestants during pregnancy are reassuring with first trimester use, it's still best to avoid them in the first trimester due to a possible very low risk for vascular issues in the fetus. Pregnant women could consider saline drops or a short-term nasal spray decongestant alternative.

3. Herbal Ingredient Warning. Watch out for herbal ingredients in many over-the-counter medications. Chances are they have not been studied in pregnancy.

4. Throat Lozenges and Vitamin Overload. Throat lozenges contain mostly sugar, however, some may contain other ingredients such as zinc or vitamin C. When taking vitamin C, the recommended daily allowance during pregnancy is 80-100 mg per day and zinc is only 11 mg per day.

5. Cough Syrups and Alcohol. Some cough syrups contain up to 10 percent alcohol. Get alcohol-free cough syrup. Your developing baby doesn’t need the alcohol exposure in addition to the other medications.

Friday, October 14, 2011

Exercise Before and During Early Pregnancy Increases Two Beneficial Proteins for Mothers-to-Be

A role in preventing preeclampsia?

Bethesda, Md. –Although exercise is generally considered to be a good thing for people with high blood pressure, it has traditionally been considered too risky for women who are also pregnant. Some studies suggest that exercise has benefits such as decreasing the risk of women developing preeclampsia, a condition that raises blood pressure to dangerously high levels but how this might happen has remained unknown. New research using an animal model falls into the “pro-exercise” camp: It suggests that exercise before conception and in the early stages of pregnancy may protect a mother-to-be by stimulating the expression of two proteins thought to play a role in blood vessel health.

The study was led by Jeffrey Gilbert of the University of Oregon’s Department of Human Physiology, while he was with the University of Minnesota Medical School. Dr. Gilbert will present the research at the Physiology of Cardiovascular Disease: Gender Disparities conference, October 12–14 at the University of Mississippi in Jackson. The conference is sponsored by the American Physiological Society with additional support from the American Heart Association. His presentation is entitled, “Exercise Training Before and During Pregnancy Improves Endothelial Function and Stimulates Cytoprotective and Antioxidant Pathways in the Pregnant Rat.”


In the study, female rats were separated into two groups, the exercise group and the control group, and later impregnated. The exercise group ran voluntarily on an activity wheel for six weeks prior to and during pregnancy, with running times and distances monitored weekly. The control group did not exercise. The team analyzed tissue samples taken from both groups late in their pregnancies.

The researchers found that the rats in the exercise group had higher levels of a circulating protein called vascular endothelial growth factor (VEGF) than those in the control group. VEGF and a pregnancy specific version of the protein called placental growth factor (PlGF) are important because not only do they stimulate the development of new blood vessels, they also maintain normal vessel function which in turn promotes good cardiovascular health.

According to Dr. Gilbert, finding increased VEGF in the exercise group has important implications for understanding, and perhaps preventing, preeclampsia. He noted that clinical and experimental studies have found that high levels of a protein called sFlt-1 can bind up the mothers’ circulating levels of PlGF and VEGF and can lead to preeclampsia.

The researchers also saw that when VEGF increased, endothelial function increased. The endothelium is a thin layer of cells that line the inside of blood vessels. It reduces turbulence in blood flow, which allows blood to be pumped further with each heartbeat, thus taking stress off the heart.

Heat Shock Proteins

The team also found that the rats in the exercise group had increased amounts of heat shock proteins (HSPs) compared to those that did not exercise. One HSP in particular, HSP 90, is thought to play a vital role in maintaining the blood vessels of the heart. It works in sync with VEGF and nitric oxide to dilate blood vessels so that blood flows more freely, which lowers blood pressure. Increased expression of HSPs as a result of exercise could provide a preconditioning effect that may help protect against cellular damage in the placenta during pregnancies complicated by high blood pressure.

“There have been many studies about exercise and pregnancy, but not at the molecular level,” said Dr. Gilbert. “We hope to learn whether stimulating these proteins with exercise before pregnancy or early during pregnancy can lower a woman’s risk for preeclampsia.”

Wednesday, October 12, 2011

Folic Acid in Early Pregnancy Associated With Reduced Risk of Severe Language Delay in Children

Use of folic acid supplements by women in Norway in the period 4 weeks before to 8 weeks after conception was associated with a reduced risk of the child having severe language delay at age 3 years, according to a study in the October 12 issue of JAMA

"Randomized controlled trials and other studies have demonstrated that periconceptional [the period from before conception to early pregnancy] folic acid supplements reduce the risk of neural tube defects. To our knowledge, none of the trials have followed up their sample to investigate whether these supplements have effects on neurodevelopment that are only manifest after birth," the authors write.

Christine Roth, M.Sc., Clin.Psy.D., of the Norwegian Institute of Public Health, Oslo, and colleagues conducted a study to investigate whether maternal use of folic acid supplements was associated with a reduced risk of severe language delay among offspring at age 3 years. "Unlike the United States, Norway does not fortify foods with folic acid, increasing the contrast in relative folate status between women who do and do not take folic acid supplements," the researchers write. Pregnant women were recruited for the study beginning in 1999, and data were included on children born before 2008 whose mothers returned the 3-year follow-up questionnaire by June 16, 2010. Maternal use of folic acid supplements within the interval from 4 weeks before to 8 weeks after conception was the exposure. The primary outcome measured for the study was children's language competency at age 3 years as gauged by maternal report on a 6-point ordinal language grammar scale. Children with minimal expressive language (only 1-word or unintelligible utterances) were rated as having severe language delay.

The main analysis for the study included 38,954 children (19,956 boys and 18,998 girls). Of these children, 204 (0.5 percent) were rated as having severe language delay (159 [0.8 percent] boys and 45 [0.2 percent) girls). Children whose mothers took no dietary supplements in the specified exposure interval were the reference group (n = 9,052 [24.0 percent], with severe language delay in 81 children [0.9 percent]). Data for 3 patterns of exposure to maternal dietary supplements were: other supplements, but no folic acid (n = 2,480 [6.6 percent], with severe language delay in 22 children [0.9 percent]); folic acid only (n = 7,127 [18.9 percent], with severe language delay in 28 children [0.4 percent]); and folic acid in combination with other supplements (n = 19,005 [50.5 percent], with severe language delay in 73 children [0.4 percent]).

The researchers write that maternal use of supplements containing folic acid within the period from 4 weeks before to 8 weeks after conception was associated with a substantially reduced risk of severe language delay in children at age 3 years. "We found no association, however, between maternal use of folic acid supplements and significant delay in gross motor skills at age 3 years. The specificity provides some reassurance that there is not confounding by an unmeasured factor. Such a factor might be expected to relate to both language and motor delay."

The authors add that to their knowledge, no previous prospective observational study has examined the relation of prenatal folic acid supplements to severe language delay in children.

"If in future research this relationship were shown to be causal, it would have important implications for understanding the biological processes underlying disrupted neurodevelopment, for the prevention of neurodevelopmental disorders, and for policies of folic acid supplementation for women of reproductive age."

Thursday, October 6, 2011

Evidence Review: Extra Calcium During Pregnancy Has No Benefits

Except To Prevent Hypertension

Source: Health Behavior News Service

Most physicians instruct pregnant women to increase their calcium intake, but a new evidence review of potential benefits of calcium supplementation for mom and baby found none, except for the prevention of pregnancy-related hypertension.
Experts agree that during pregnancy, a mother’s diet and nutritional status contribute significantly to the health and well-being of her offspring. Yet, the effects of supplementation with calcium, or the amounts to supplement, have remained unclear.
A review led by researcher Pranom Buppasiri, MD, of the department of obstetrics and gynecology at Khon Kaen University in Thailand, shows that calcium supplementation has no effect on preventing preterm birth or low infant birth weight and no effect on bone density in pregnant women. Bupparsiri notes, however, that previous reviews have shown that calcium supplementation does help in the prevention of preeclampsia.
Preeclampsia is a dangerous condition marked by hypertension and protein in the urine that can develop into serious complications for the mother and baby. The definitive treatment for preeclampsia is delivery of the baby, often resulting in preterm and/or low birth weight babies.
More than 16,000 women participated in the 21 studies included in the review. The review did find a small difference in average infant birth weight, but the authors were unable to ascertain the clinical significance in the diverse population examined.
Buppasiri and colleagues’ review appears in the latest issue of The Cochrane Library, a publication of the Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.
Stephen Contag, MD, a perinatalogist at Sinai Hospital of Baltimore's Institute of Maternal Fetal Medicine called the review confusing and said, “There is an inherent confounding effect between the two interventions in that whenever maternal hypertensive disease is prevented, preterm labor is less likely to occur.” In other words, calcium supplementation might prevent preterm labor indirectly by preventing high blood pressure. He added that, “the definitive treatment for pregnancy related hypertensive disease is delivery, which often occurs preterm depending on the severity and timing of onset.”
Contag stated that according to current Institute of Medicine recommendations, “calcium supplementation is recommended in addition to dietary calcium intake, in order to achieve recommended daily allowance of 1,000 mg/day.”
However, John McDougall, MD, an internist, nutrition expert and medical director of the McDougall Program in Santa Rosa, California, cited a July 2010 study in the British Medical Journal to support the fact that he does not prescribe calcium supplements, because they increase the risk of heart attacks and strokes.
“Certainly, taking isolated concentrated minerals, such as calcium, creates physiological imbalances in the body,” McDougall said in a commentary regarding the July study. “Immediately after consuming calcium supplements, the calcium in the blood increases. Thereafter, the body must adjust to this large burden of minerals. One of the adverse effects appears to be artery damage.”
Buppasiri said there were still not enough studies to draw a meaningful conclusion about supplementation. “We need more high quality studies to address this review question, especially in low calcium intake populations,” he said.

Tuesday, October 4, 2011

Higher quality diet associated with reduced risk of some birth defects

Healthier dietary choices by pregnant women are associated with reduced risks of birth defects, including neural tube defects and orofacial clefts, according to a study published Online First by the Archives of Pediatrics & Adolescent Medicine, one of the JAMA/Archives journals.

The authors state in background information that folic acid supplementation and food fortification has been effective in preventing neural tube defects, but folic acid does not prevent all birth defects. "Nutrition research on birth defects has tended to focus on one nutrient (or nutritional factor) at a time," the authors write. "However, the reality of nutrition is much more complex."

Suzan L. Carmichael, Ph.D., from Stanford University, Stanford, Calif., and colleagues used data from the National Birth Defects Prevention Study "to examine whether better maternal diet quality was associated with reduced risk for selected birth defects." The data were collected in 10 states from pregnant women with estimated due dates from October 1997 through December 2005. Information was collected via telephone interviews with 72 percent of case and 67 percent of control mothers. Included in the analysis were 936 cases with neural tube defects, 2,475 with orofacial clefts, and 6, 147 controls without birth defects. Mothers reported their food intake using a questionnaire. The researchers developed two diet quality indices that focused on overall diet quality based on the Mediterranean Diet (Mediterranean Diet Score or MDS) and the U.S. Department of Agriculture Food Guide Pyramid (Diet Quality Index or DQI).

"…Increasing diet quality based on either index was associated with reduced risks for the birth defects studied," the authors found. "Most mothers of controls [children without birth defects] were non-Hispanic white and had more than a high school education; 19 percent smoked, 38 percent drank alcohol, and 78 percent took folic-acid-containing supplements during early pregnancy; and 16 percent were obese," the authors report. "Women who were Hispanic had substantially higher values for the DQI and the MDS, whereas values were lower among women with less education and women who smoked, did not take supplements, or were obese…"

"Based on two diet quality indices, higher maternal diet quality in the year before pregnancy was associated with lower risk for neural tube defects and orofacial clefts. This finding persisted even after adjusting for multiple potential confounders such as maternal intake of vitamin/mineral supplements," the authors write. "These results suggest that dietary approaches could lead to further reduction in risks of major birth defects and complement existing efforts to fortify foods and encourage periconceptional multivitamin use," the authors conclude.

(Arch Pediatr Adolesc Med. Published online October 3, 2011. doi:10.1001/archpediatrics.2011.185. Available pre-embargo to the media at

Editor's Note: This project was partially supported by grants from the National Institutes of Health and the Centers for Disease Control and Prevention. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

Editorial: The Importance of Food

In an accompanying editorial, David R. Jacobs, Jr., Ph.D., from the University of Minnesota, Minneapolis, and colleagues note that while maternal intake of folate is important for fetal development, recent studies suggest the supplemental folic acid may have adverse health effects on older adults.

"The importance of the findings of Carmichael et al lies in showing that women obtain benefit from the consumption of a high-quality diet, beyond the benefits derived through grain fortification. This raises the question of whether a high-quality diet alone may be sufficient to prevent NTDs (neural tube defects) – a strategy that would also remove the potential harm from fortification."

"The lesson from the article by Carmichael et al is an important one: people, including women of childbearing age, should eat good food."

"Reduction of NTDs may be achievable by diet alone, at the same time reducing potential risk for other chronic diseases in the rest of the population."

Monday, September 26, 2011

Pregnant women who exercise protect their offspring against long-term neurodegenerative diseases


New research in the FASEB Journal suggests that prenatal exercise improves brain plasticity, decreases toxic protein deposits, inflammation and oxidative stress, which wards off Alzheimer's and other diseases

Bethesda, MD—If you are pregnant, here's another reason to work out: you will reduce the chances of your new baby developing neurodegenerative diseases, such as Alzheimer's, later in life. A new research report published online in The FASEB Journal ( shows that mice bred to develop a neurodegenerative disease roughly equivalent to Alzheimer's disease showed fewer signs of the disease and greater brain plasticity later in life when their mothers exercised regularly than those whose mothers did not exercise.

"This research provides an experimental rationale for the effects of beneficial behavioral stimuli experienced by the pregnant mother affecting the disease status of an as yet-unborn child. Epigenetic alterations (alterations in gene and protein expression caused by mechanisms other than changes in the underlying DNA sequence) provide a most probable mechanism by which mothers could have transferred their own behavioral experience to their progeny," said Kathy Keyvani, M.D., a researcher involved in the work from the Institute of Pathology and Neuropathology at the University Hospital Essen in Essen, Germany. "A better understanding of the underlying pathways may provide novel treatment and/or prevention strategies for Alzheimer's disease and bring more insight into the fascinating link between brain and behavior."

To make this discovery, Keyvani and colleagues mated male mice that express a mutant form of the APP gene found in some Alzheimer's patients with healthy female wild-type mice. After weaning, healthy and "Alzheimer-diseased" offspring were kept in standard cages for five months. Mouse brains were examined for signs of disease shortly thereafter. The "Alzheimer-diseased" mice whose mothers ran on a exercise wheel during pregnancy had fewer Beta-amyloid plaques, smaller plaque size, less inflammation, less oxidative stress, and a better functioning vascular network than those whose mothers did not run. Additionally, the mice whose mothers ran on the wheel also showed an up-regulation of plasticity-related molecules, which are indicators for more and better connections between the nerve cells.

"No one is resistant to the health benefits of exercise," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal, "and this research confirms that reasonable workouts can have a lifetime of benefits for your offspring. Whether you work out at home or go to the gym, you should do it for the sake of your health and that of your offspring."

Monday, September 19, 2011

Low-Fat Yogurt Intake When Pregnant Linked to Increased Risk of Child Asthma and Hay Fever

Eating low-fat yogurt whilst pregnant can increase the risk of your child developing asthma and allergic rhinitis (hay fever), according to recent findings.

The study aimed to assess whether fatty acids found in dairy products could protect against the development of allergic diseases in children.

The researchers assessed milk and dairy intake during pregnancy and monitored the prevalence of asthma and allergic rhinitis using registries and questionnaires in the Danish National Birth Cohort.

The results showed that milk intake during pregnancy was not associated with increased risk of developing asthma and it actually protected against asthma development. However, women who ate low-fat yogurt with fruit once a day were 1.6-times more likely to have children who developed asthma by age 7, compared with children of women who reported no intake. They were also more likely to have allergic rhinitis and to display current asthma symptoms.

The researchers suggest that non-fat related nutrient components in the yogurt may play a part in increasing this risk. They are also looking at the possibility that low-fat yogurt intake may serve as a marker for other dietary and lifestyle factors.

Ekaterina Maslova, lead author from the Harvard School of Public Health, who has been working with data at the Centre for Fetal Programming at Statens Serum Institut, said: "This is the first study of its kind to link low-fat yogurt intake during pregnancy with an increased risk of asthma and hay fever in children. This could be due to a number of reasons and we will further investigate whether this is linked to certain nutrients or whether people who ate yogurt regularly had similar lifestyle and dietary patterns which could explain the increased risk of asthma."

Friday, September 16, 2011

Moms who eat high-fat diet before, during pregnancy 'program' babies to be fat, at risk

This is the first study to demonstrate that a long-term maternal high-fat diet results in the deposition, in utero, of excess body fat in the newborn

New research in mice indicates that babies born to moms who eat a high-fat diet before and during pregnancy have a higher fat mass and smaller livers than babies whose moms consume low-fat fare, according to scientists at Oregon Health & Science University Doernbecher Children's Hospital.

The good news, the researchers report, is that moms who switch to a low-fat diet during pregnancy considerably reduce the risk of these negative effects. Their findings are published online in the American Journal of Physiology and Endocrinology Metabolism, a publication of the American Physiological Society.

Previous research has shown babies who receive too much or too little nutrition in the womb experience profound and permanent changes in their development — including alterations in the structure of the liver, brain and pancreas — that increase their susceptibility to developing various diseases later in life, including obesity, diabetes and cardiovascular disease.

And given that nearly half of women of childbearing age are overweight or obese in the United States, according to the Centers for Disease Control and Prevention, there is a pressing need to inform women and their health care providers of the inherent dangers maternal overeating poses to their child's future health and risk of chronic disease.

"One of the key findings here is that the offspring are born with a marked shift in body composition, away from lean mass and toward fat mass, prior to any dietary exposure in the offspring themselves," said principal investigator Stephanie M. Krasnow, Ph.D., a scientist in the Papé Family Pediatric Research Institute at OHSU Doernbecher Children's Hospital.

Krasnow and colleagues in the Daniel Marks Lab used a mouse model to examine how consumption of a high-fat diet during pregnancy effects body composition in the newborn. Female mice were fed either a low-fat or high-fat diet for six months and were mated with male mice after 4, 12 and 23 weeks. The females who ate a high-fat diet gained more body weight and had a higher fat mass than the females who ate a low-fat diet. And on the day of birth, babies born to females who had consumed a high-fat food had more body fat, less lean mass, and smaller livers than the newborns of females that consumed low-fat food.

These changes in body composition and organ size occurred before the female mice eating a high-fat diet became obese, the researchers report. And even when the females were not obese, eating a high-fat diet prior to and during pregnancy "programmed" their unborn babies to have increased body fat and smaller livers at birth. Fortunately, the researchers found, switching to a low-fat diet just during pregnancy prevented the infants from accumulating excess fat mass in utero and also prevented their having smaller livers.

"These findings demonstrate that changing to a low-fat diet during pregnancy minimizes the harmful effects of maternal obesity on the newborn's body composition, potentially reducing the child's risk of developing obesity and related diseases later in life," said Krasnow.

Tuesday, September 6, 2011

Anti-inflammatory drugs taken in early pregnancy more than double risk of miscarriage

The risk of miscarriage is 2.4 times greater for women who took any type and dosage of nonaspirin nonsteroidal anti-inflammatory drugs (NSAIDs) in early pregnancy, according to a study in CMAJ (Canadian Medical Association Journal) (pre-embargo link only)

Nonaspirin NSAIDs are a class of drugs that include naproxen, ibuprofen, diclofenac, and celecoxib, and are one of the most common medications used during pregnancy. However, there are concerns about use of these drugs in pregnancy, although studies on the risks have been inconsistent.

Researchers from the University of Montreal, CHU Ste-Justine, Quebec, and École Nationale de la Statistique et de l'Analyse de l'Information, Rennes, France, undertook a study to determine the risk of miscarriage associated with the types and dosages of nonaspirin NSAIDs. They looked at a total of 4705 cases of miscarriage up to the 20th week of gestation, 352 (7.5%) of whom took nonaspirin NSAIDs. Of the 47 050 women in the control group who did not miscarry, 1213 (2.6%) had been exposed to nonaspirin NSAIDs. The data came from the Quebec Pregnancy Registry, which provides information on filled prescriptions, physician visits and diagnoses, and hospitalisations during pregnancy.

Women ranged in age from 15 to 45 years old on the first day of gestation and were insured by the Régie de l'Assurance Maladie du Québec (RAMQ) for their medications for at least one year prior to and during pregnancy. Exposure to nonaspirin NSAIDs was defined as having filled at least one prescription for any type of the drug during the first 20 weeks of pregnancy or in the two weeks prior to the start of the pregnancy.

Ibuprofen is the only nonaspirin NSAID available over the counter in Quebec, and women in the RAMQ drug plan can have that prescribed as a prescription. Naproxen was the most commonly used nonaspirin NSAID followed by ibuprofen.

"The use of nonaspirin NSAIDs during early pregnancy is associated with statistically significant risk (2.4-fold increase) of having a spontaneous abortion," writes Dr. Anick Bérard, from the University of Montreal and the Director of the Research Unit on Medications and Pregnancy at CHU Ste-Justine. "We consistently saw that the risk of having a spontaneous abortion was associated with gestational use of diclofenac, naproxen, celecoxib, ibuprofen and rofecoxib alone or in combination, suggesting a class effect."

The highest risk was associated with diclofenac alone and the lowest risk was in users of rofecoxib alone. However, dosage of nonaspirin NSAIDs did not appear to affect risk.

These findings are consistent with other studies but are novel with regards to the nonaspirin NSAIDs types and dosages.

"Given that the use of nonaspirin NSAIDs during early pregnancy has been shown to increase the risk of major congenital malformations1 and that our results suggest a class effect on the risk of clinically detected spontaneous abortion, nonaspirin NSAIDs should be used with caution during pregnancy.," the authors conclude.

Wednesday, August 3, 2011

Diet during pregnancy and breast cancer risk reduction in female offspring

During pregnancy, women are counseled to refrain from consuming certain types of foods, beverages and medications in order to avoid jeopardizing the health and development of the fetus. In fact, the American Pregnancy Association has a list of a dozen items they recommend expectant mothers omit from their diets. However, there are some additions, such as folic acid, that, when taken before and/or during pregnancy, can actually reduce the risk of birth defects and other disorders.

Research presented today at the Era of Hope conference, a scientific meeting hosted by the Department of Defense Breast Cancer Research Program (BCRP), reveals findings suggesting that if an expectant mother increases her consumption of foods high in certain fatty acids or nutrients during her pregnancy, she can potentially reduce the risk of breast cancer in her female offspring.

The research delves into breast cancer risk reductions attributed to the fetus when the mother, while pregnant, increases omega 3 fatty acids within her diet or consumes dietary methyl nutrients (methionine, choline, folate and vitamin B12). Some findings hypothesize that these diet augmentations may even prevent breast cancer from ever developing in the offspring.

"This is exciting and intriguing research," said Captain Melissa Kaime, M.D., Director of the Congressionally Directed Medical Research Programs (CDMRP), under which the BCRP is managed. "To be able to reduce the risk and possibly prevent this devastating disease before birth is an incredible notion; the BCRP is proud to support research with such potential."

Maternal Consumption of Omega 3 Fatty Acids to Reduce Breast Cancer Risk in Offspring
Principal Investigator: Philippe T. Georgel, PhD, Marshall University

Maternal dietary alterations, including increasing the consumption of omega 3 fatty acids, may reduce the risk of breast cancer to the fetus by causing epigenetic changes in utero and later through nursing. These changes may alter gene expression permanently, a change referred to as imprinting. Researchers at Marshall University conducted a study to investigate whether having a diet rich in omega 3s while pregnant would result in changes to fetal mammary gland gene expression, thereby reducing the chance that female offspring would later develop breast cancer.

In this study, there was a reduced incidence of mammary gland cancer observed for the offspring of mice that, while pregnant and nursing, consumed a diet containing canola oil, rich in omega 3, compared with the offspring of mice that, while pregnant and nursing, consumed a diet containing corn oil rich in omega 6 fatty acids. Reviewing the gene expression profiles of both groups showed that many genes related to cancer development differed between the two groups. Significant differences in the patterns of two important epigenetic markers were also observed.

"Pregnant women should be mindful of what they consume since their diet may incite epigenetic changes that could impact the development of their offspring, not just in utero but also for time to come," said Dr. Philippe Georgel, Marshall University. "Additional research continues, as we seek to elucidate the effect of diet on breast cancer-specific gene expression."

In Utero Exposure to Dietary Methyl Nutrients and Breast Cancer Risk in Offspring
Principal Investigator: Chung S. Park PhD, North Dakota State University

Links are being drawn to complete mammary gland development of the mother during pregnancy and reduction in breast cancer risk in her daughters. Supplementing the mother's diet with lipotropic nutrients (methionine, choline, folate and vitamin B12) is thought to increase methyl metabolism which stimulates the full development of the mammary gland, thereby inducing an epigenetic imprint in the mammary gland of the fetus and decreasing its breast cancer risk. Investigators at North Dakota State University are researching this link with the overall objective of determining the extent to which supplementing diets with methyl nutrients during pregnancy reduces the offspring's overall breast cancer susceptibility.

The study looked at 45 pregnant rats and randomized them into two groups: one to receive a control and the other to be fed a methyl-supplemented diet. Once the pups were born, they were separated into three additional groups depending on the feeding regime of their mother. When the female pups reached a specific age, they were exposed to a chemical that induced breast cancer and researchers charted when the first tumor appeared and measured all tumor sizes and volumes. Results demonstrated that the offspring from the methyl-supplemented diet group showed a decrease in tumor incidence and growth when compared to the control group. Also, they had fewer tumors and fewer tumors that multiplied.

"The conclusions of this study suggest that we may be able to prevent the development of breast cancer in daughters of women at risk for breast cancer by supplementing the mother's diet during pregnancy," said Dr. Chung Park, North Dakota State University. "We look forward to exploring this study further to strengthen the implications of these initial findings."

Gum Disease Can Increase the Time It Takes to Become Pregnant

Professor Roger Hart told the annual meeting of the European Society of Human Reproduction and Embryology that the negative effect of gum disease on conception was of the same order of magnitude as the effect of obesity.

Periodontal (gum) disease is a chronic, infectious and inflammatory disease of the gums and supporting tissues. It is caused by the normal bacteria that exist in everyone's mouths, which, if unchecked, can create inflammation around the tooth; the gum starts to pull away from the tooth, creating spaces (periodontal pockets) that become infected. The inflammation sets off a cascade of tissue-destructive events that can pass into the circulation. As a result, periodontal disease has been associated with heart disease, type 2 diabetes, respiratory and kidney disease, and problems in pregnancy such as miscarriage and premature birth. Around 10% of the population is believed to have severe periodontal disease. Regular brushing and flossing of teeth is the best way of preventing it.

Prof Hart, who is Professor of Reproductive Medicine at the University of Western Australia (Perth, Australia) and Medical Director of Fertility Specialists of Western Australia, said: "Until now, there have been no published studies that investigate whether gum disease can affect a woman's chance of conceiving, so this is the first report to suggest that gum disease might be one of several factors that could be modified to improve the chances of a pregnancy."

The researchers followed a group 3737 pregnant women, who were taking part in a Western Australian study called the SMILE study, and they analysed information on pregnancy planning and pregnancy outcomes for 3416 of them.

They found that women with gum disease took an average of just over seven months to become pregnant -- two months longer than the average of five months that it took women without gum disease to conceive.

In addition, non-Caucasian women with gum disease were more likely to take over a year to become pregnant compared to those without gum disease: their increased risk of later conception was 13.9% compared to 6.2% for women without gum disease. Caucasian women with gum disease also tended to take longer to conceive than those who were disease-free but the difference was not statistically significant (8.6% of Caucasian women with gum disease took over one year to conceive and 6.2% of women with gum disease).

Information on time to conception was available for 1,956 women, and of, these, 146 women took longer than 12 months to conceive -- an indicator of impaired fertility. They were more likely to be older, non-Caucasian, to smoke and to have a body mass index over 25 kg/m2. Out of the 3416 women, 1014 (26%) had periodontal disease.

Prof Hart said: "Our data suggest that the presence of periodontal disease is a modifiable risk factor, which can increase a woman's time to conception, particularly for non-Caucasians. It exerts a negative influence on fertility that is of the same order of magnitude as obesity. This study also confirms other, known negative influences upon time to conception for a woman; these include being over 35 years of age, being overweight or obese, and being a smoker. There was no correlation between the time it took to become pregnant and the socio-economic status of the woman.

"All women about to plan for a family should be encouraged to see their general practitioner to ensure that they are as healthy as possible before trying to conceive and so that they can be given appropriate lifestyle advice with respect to weight loss, diet and assistance with stopping smoking and drinking, plus the commencement of folic acid supplements. Additionally, it now appears that all women should also be encouraged to see their dentist to have any gum disease treated before trying to conceive. It is easily treated, usually involving no more than four dental visits.

"The SMILE study was one of the three largest randomised controlled trials performed in Western Australia. It showed conclusively that although treatment of periodontal disease does not prevent pre-term birth in any ethnic group, the treatment itself does not have any harmful effect on the mother or fetus during pregnancy."

Prof Hart said that the reason why pregnancies in non-Caucasian women were more affected by gum disease could be because these women appeared to have a higher level of inflammatory response to the condition.

Monday, August 1, 2011

Study shows protective benefits of DHA taken during pregnancy

An Emory University study published online today in Pediatrics suggests consuming Omega 3 fatty acids during pregnancy helps protects babies against illness during early infancy.

The randomized, placebo-controlled trial followed approximately 1,100 pregnant women and 900 infants in Mexico. The women were supplemented daily with 400 mg of Docosahexaenoic Acid (DHA) supplements in the algal form or placebo from 18 to 22 weeks gestation through childbirth.

Researchers found those whose mothers took DHA supplements had fewer colds and shorter illnesses at one, three and six months of age.

"This is a large scale, robust study that underscores the importance of good nutrition during pregnancy," says Usha Ramakrishnan, PhD, associate professor, Hubert Department of Global Health at Emory's Rollins School of Public Health. "Our findings indicate that pregnant women taking 400 mg of DHA are more likely to deliver healthier infants."

At one month of age, the infants in the DHA group experienced a reduced occurrence of cold symptoms by 25 percent, including a shorter duration of cough, phlegm and wheezing.

At age three months, the infants in the DHA group spent 14 percent less time ill.

At six months of age, infants in the DHA group experienced shorter duration of fever, nasal secretion, difficulty breathing and rash, though longer duration of vomiting. Ramakrishnan and her colleagues have previously reported findings that show offspring of women pregnant with their first child who received 400 mg DHA during pregnancy delivered babies who were 100 grams heavier at birth and 3/4 cm longer at 18 months of age.

The study, funded by the NIH and the March of Dimes Foundation, also found increased DHA levels in breast milk. All of the infants participating in the study were breastfed.

Wednesday, July 20, 2011

Caffeine consumption linked to female infertility


Caffeine reduces muscle activity in the Fallopian tubes that carry eggs from a woman's ovaries to her womb. "Our experiments were conducted in mice, but this finding goes a long way towards explaining why drinking caffeinated drinks can reduce a woman's chance of becoming pregnant," says Sean Ward, professor of physiology and cell biology, at the University of Nevada School of Medicine, who conducted the study.

Ward's study was recently published in the British Journal of Pharmacology.

Human eggs are microscopically small, but need to travel to a woman's womb if she is going to have a successful pregnancy. Although the process is essential for a successful pregnancy, scientists know little about how eggs move through the muscular Fallopian tubes. It was generally assumed that tiny hair-like projections, called cilia, in the lining of the tubes, waft eggs along assisted by muscle contractions in the tube walls.

By studying tubes from mice, Ward and his team discovered that caffeine stops the actions of specialized pacemaker cells in the wall of the tubes. These cells coordinate tube contractions so that when they are inhibited, eggs can't move down the tubes. In fact these muscle contractions play a bigger role than the beating cilia in moving the egg towards the womb.

"This provides an intriguing explanation as to why women with high caffeine consumption often take longer to conceive than women who do not consume caffeine," said Ward.

Discovering the link between caffeine consumption and reduced fertility has benefits.

"As well as potentially helping women who are finding it difficult to get pregnant, a better understanding of the way Fallopian tubes work will help doctors treat pelvic inflammation and sexually-transmitted disease more successfully," said Ward.

It could also increase our understanding of what causes ectopic pregnancy, an extremely painful and potentially life-threatening situation in which embryos get stuck and start developing inside a woman's Fallopian tube.

Tuesday, July 12, 2011

Smoking causes serious birth defects

To dispel any uncertainty about the serious harm caused by smoking to babies and pregnant women, the first-ever comprehensive systematic review of all studies over the past 50 years has established clearly that maternal smoking causes a range of serious birth defects including heart defects, missing/deformed limbs, clubfoot, gastrointestinal disorders, and facial disorders (for example, of the eyes and cleft lip/palate).

Smoking during pregnancy is also a risk factor for premature birth, says Dr. Michael Katz, senior Vice President for Research and Global Programs of the March of Dimes. He says the March of Dimes urges all women planning a pregnancy or who are pregnant to quit smoking now to reduce their chance of having a baby born prematurely or with a serious birth defect. Babies who survive being born prematurely and at low birthweight are at risk of other serious health problems, Dr. Katz notes, including lifelong disabilities such as cerebral palsy, intellectual disabilities and learning problems. Smoking also can make it harder to get pregnant, and increases the risk of stillbirth.

About 20 percent of women in the United States reported smoking in 2009. Around the world, about 250 million women use tobacco every day and this number is increasing rapidly, according to data presented at the 2009 14th World Conference on Tobacco or Health in Mumbai.

The new study, "Maternal smoking in pregnancy and birth defects: a systematic review based on 173,687 malformed cases and 11.7 million controls," by a team led by Allan Hackshaw, Cancer Research UK & UCL Cancer Trials Centre, University College London, will be published online today in Human Reproduction Update from the European Society of Human Reproduction and Embryology.

When women smoke during pregnancy, the unborn baby is exposed to dangerous chemicals like nicotine, carbon monoxide and tar, Dr. Katz says. These chemicals can deprive the baby of oxygen needed for healthy growth and development.

During pregnancy, smoking can cause problems for a woman's own health, including:

ectopic pregnancy;
vaginal bleeding;
placental abruption, in which the placenta peels away, partially or almost completely, from the uterine wall before delivery;
placenta previa, a low-lying placenta that covers part or all of the opening of the uterus.

Smoking is also known to cause cancer, heart disease, stroke, gum disease and eye diseases that can lead to blindness.

Wednesday, July 6, 2011

Undernourishment in Pregnant, Lactating Females = Vulnerability to type 2 diabetes

A new study published by the American Physiological Society offers the strongest evidence yet that vulnerability to type 2 diabetes can begin in the womb, giving new insight into the mechanisms that underlie a potentially devastating disease at the center of a worldwide epidemic. The study, conducted in baboon primates, finds that when mothers are even moderately undernourished while pregnant and breastfeeding, their offspring are consistently found to be prediabetic before adolescence. It is the first time that diabetes has been shown to have prenatal origins in a primate model.

According to Peter W. Nathanielsz, senior author of the study, "We pass more biological milestones before we are born and in the early weeks of life than at any other time." Poor maternal nutrition, which translates to less sustenance for growing fetuses, is a stubborn problem in parts of the U.S. and the developing world, Nathanielsz said. Thus, "Poor nutrition at critical periods of development can hinder growth of essential organs such as the pancreas, which sees a significantly decrease in its ability to secrete insulin. Our study is the first to show in a primate that poor nutrition during fetal and early life can damage the pancreas and predispose one to type 2 diabetes."

The study, "Emergence of insulin resistance in juvenile baboon offspring of mothers exposed to moderate maternal nutrient reduction" was conducted by Nathanielsz and colleagues Jaehyek Choi, Cun Li, and Thomas J. McDonald of the School of Medicine at the University of Texas Health Science Center at San Antonio, and Anthony Comuzzie and Vicki Mattern of the Texas Biomedical Research Institute in San Antonio. The study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases. It is published in the online edition of the American Journal of Physiology -- Regulatory, Integrative and Comparative Physiology.


Type 2 diabetes occurs when the body develops resistance to insulin, a hormone that regulates blood sugar. Although the body may initially compensate by secreting more insulin, eventually the pancreas cannot produce enough of the hormone to keep blood sugar from rising. In poorly controlled diabetes, elevated blood sugar severely damages the heart, blood vessels, eyes, kidneys and nerves. The consequences can be fatal and include heart disease, stroke, amputations, blindness and kidney failure.

Worldwide, diabetes is an escalating public health crisis. According to estimates from the World Health Organization (WHO), 366 million people will be diabetic by the 2030, up from 171 million in 2000. This is a 114 percent projected increase.

Formerly called "adult-onset diabetes," type 2 diabetes is seen increasingly in children at earlier and earlier ages. Excess body weight and physical inactivity are known causes, but Nathanielsz and his collaborators have long been interested in whether some individuals might be predisposed to diabetes from birth, or even earlier. Nathanielsz conducts research on this and similar topics through the Center for Pregnancy and Newborn Research in the UT Health Science Center's Department of Obstetrics and Gynecology.

The Study

For this study, to avoid the complication of influences from genes, researchers selected 18 female baboons similar in age and other observable characteristics and housed them with a fertile male baboon. All females became pregnant. From 30 days of gestation, 12 females were randomly assigned to be fed an appropriate diet for their weight. The other six received 70 percent of the chow given to control females on a weight-adjusted basis. The female baboons continued on their respective diets through delivery and the weaning of their offspring. Once the young baboons were weaned, they were fed normal diets.

Just before they reached puberty, the six young baboons from nutritionally restricted mothers showed increases in fasting glucose, fasting insulin and other hallmarks of prediabetes. The 12 young baboons whose mothers received adequate nutrition displayed none of these traits.

The central importance of this observation is that the mothers' food intake was only moderately restricted -- similar to the decrease faced in the United State by many people living with food insecurity. There are 925 million undernourished people worldwide, including 19 million in developed countries, according to the Food and Agriculture Organization of the United Nations.

The researchers conclude that even moderate nutrient deficiencies during pregnancy result in offspring predisposed to type 2 diabetes, particularly if they are exposed to other risk factors in later life, such as a Western diet and physical inactivity leading to obesity. A fetus may also receive fewer nutrients due to teenage pregnancy, where the growing mother competes with her offspring for resources; in pregnancies complicated by maternal vascular disease, which may occur in women who become pregnant later in their reproductive life; and when placental problems exist. The decrease in fetal growth observed in the newborn baboons was only about 10 percent, very similar to many human babies born growth restricted.

Asthma Linked to Depression during Pregnancy

Anxiety, stress and depression during pregnancy may lead to a greater risk of asthma for your child. Study results are published in the July issue of Annals of Allergy, Asthma & Immunology, the scientific journal of the American College of Allergy, Asthma and Immunology (ACAAI).

“Approximately 70 percent of mothers who said they experienced high levels of anxiety or depression while they were pregnant reported their child had wheezed before age 5,” said Marilyn Reyes, lead author of the study. “Understanding how maternal depression affects a child’s respiratory health is important in developing effective interventions.”

The study of 279 inner-city African-American and Hispanic women was conducted before, during pregnancy and after birth. The study results support growing research that the prenatal period is a time when children are particularly susceptible to asthma-related risks. While somewhat similar findings have been reported in non-minority populations, this study at the Columbia Center for Children’s Environmental Health is the first to report an association between stress and wheeze in minority populations.

Common asthma symptoms include:
• Coughing, especially at night
• Wheezing or whistling sound, especially when breathing out
• Trouble breathing or fast breathing that causes the skin around the ribs or neck to pull in tightly
• Frequent colds that settle in the chest

Mother’s Salt Intake Could be Key to Prenatal Kidney Development

A new animal study from Europe has drawn an association between pregnant mothers’ sodium intake and their newborn’s kidney development. Among the most significant aspects of the study’s findings is that either too much or too little salt during pregnancy had an adverse effect on the prenatal development of the offspring’s kidneys. The consequence of such disruption can lead to high blood pressure in later years.

These are the conclusions reached in the study, “Both High and Low Maternal Salt Intake in Pregnancy Alters Kidney Development in the Offspring,” conducted by Nadezda Koleganova, Grzegorz Piecha, Annett Müller, Monika Weckbach, Peter Schirmacher, and Marie-Luise Gross-Weissmann, Eberhard Ritz and Luis Eduardo Becker, all with the University of Heidelberg in Heidelberg, DE; and Jens Randel Nyengaard of the University of Aarhus, Aarhus, DK. Their study is published in the online edition of the American Journal of Physiology--Renal Physiology.


This research builds upon past studies that recognize that excessive salt intake causes secretion of endogenous cardiotonic steroids such as marinobufagenin (MBG). For the pregnant female, this can be harmful since high concentrations of MBG are correlated to low birth-weight and higher blood pressure in the offspring.
Previous research has also linked high blood pressure with a low nephron number, critical because the nephron is the basic structural and functional unit of the kidney. The nephron eliminates wastes from the body, regulates blood volume and blood pressure, controls levels of electrolytes and metabolites, and regulates blood pH. Its functions are vital to life and are regulated by the endocrine system.


Sprague-Dawley rats were fed low, intermediate or high sodium diets during pregnancy and lactation. The litters were standardized to identical size at birth with 1:1 male to female ratio. The offspring were separated from their mothers at four weeks of age and subsequently received the intermediate sodium diet. The animals had free access to water and food and their body weight, food and water consumption were monitored weekly.
The kidney structure was assessed at postnatal weeks 1 and 12, and the expression of proteins known to be involved in kidney development were examined at birth and 1 week of age. Blood pressure was measured by telemetry in male offspring between the ages of two and nine months.


The researchers found that the number of glomeruli (the main structural unit of the kidney) during weeks 1-12 were significantly lower, and the measured blood pressure for males after the fifth month was higher in offspring of mothers on high- or low- compared with intermediate-sodium diet. High salt diet was paralleled by higher concentrations of marinobufagenin in the amniotic fluid and an increase in the expression of both GDNF and its inhibitor, sprouty-1 in the offspring’s kidney. The expression of FGF-10, a genetic signal responsible for kidney development, was lower in offspring of mothers on low-sodium diet and the expression of Pax-2 and FGF-2, tissue-specific genes that determine cell lineages, tissue patterning, and cellular proliferation was lower in offspring of mothers on high-sodium diet.

Importance of the Findings

Taken together the above findings indicate that both too low and too high maternal salt intakes retard development of new glomeruli, resulting in a nephron deficit. If the findings in the animals in this study can be extrapolated to humans, both too low and too high salt intake during pregnancy would be a risk factor for hypertension and renal damage in the offspring.

In women, each mother-to-be has specific health issues and conditions that require guidance from a health provider. This study sheds light on the issue of salt intake during pregnancy and draws attention to the possible consequences of consuming too much or too little salt during pregnancy and the impact it may have on the kidney development of an offspring.

Pre-pregnancy diet affects the health of future offspring

Poor maternal diet before conception can result in offspring with reduced birth weights and increased risk of developing type II diabetes and obesity.

This work, which is being presented at the Society for Experimental Biology Annual Conference in Glasgow on Saturday the 2nd of July, used an animal model to illustrate the importance of maternal diet even before pregnancy begins.

During the study mice that were fed a low protein diet for ten weeks before conception (but had a normal diet during pregnancy) gave birth to offspring that had lower birth weights, showed catch-up growth after weaning and increased insulin sensitivity.

These effects combined can lead to problems later in life. MSc researcher, Ms Anete Dudele, from the University of Aarhus, explains: "Low birth weight and catch-up growth is associated with enhanced insulin-sensitivity in young adults, this then deteriorates into insulin resistance and type II diabetes with increased age. There is also evidence that male offspring are more likely to develop obesity."

Humans and mice respond in the same way to poor diet during pregnancy; their offspring show low birth weights and increased risk of obesity, type II diabetes and cardiovascular disease. "If humans respond in the same way as mice to pre-conception diet as well then women should not only consider what they eat during pregnancy but also before pregnancy if they want to reduce the risk of their future children acquiring lifestyle diseases," says Ms. Dudele.

Cardiovascular disease is often associated with obesity and type II diabetes and future research by the team will determine whether offspring born to mothers who had poor pre-conception diets are predisposed to these types of problems as well.

Exposure to anti-depressants in pregnancy may increase autism risk

Exposure to selective serotonin reuptake inhibitors anti-depressants in early pregnancy may modestly increase risk of autism spectrum disorders, according to a Kaiser Permanente study published online in the current issue of Archives of General Psychiatry. However the researchers cautioned that the number of children exposed prenatally to SSRIs was low and that further studies are needed to validate these results

Funded by the Centers for Disease Control and Prevention, the population-based, case-control study of 1,805 children is the first to systematically address the association between prenatal SSRI exposure and ASD risk.

Researchers reported a two-fold increased risk of ASD associated with maternal treatment with SSRI anti-depressants during the year before delivery. The strongest effect was associated with first trimester treatment, said the study's lead author, Lisa Croen, PhD, director of the Autism Research Program at the Kaiser Permanente Division of Research in Oakland, Calif. She explained that in utero exposure to anti-depressant medications was reported in 6.7 percent of cases and 3.3 percent of controls.

"Our results suggest a possible, albeit small, risk to the unborn child associated with in utero exposure to SSRIs, but this possible risk must be balanced with risk to the mother of untreated mental health disorders," said Croen, who explained that further studies are needed to replicate and extend these findings.

Researchers conducted a population-based, case-control study among 298 children with ASD and 1,507 randomly selected control children drawn from the Kaiser Permanente Northern California membership. Information on maternal use of anti-depressant medications, maternal mental health history, autism and demographic characteristics was collected from medical records.

After adjusting for maternal age, race/ethnicity, education and child's birth weight, gender, birth year, and facility of birth, mothers of children subsequently diagnosed with ASD were twice as likely to have at least one anti-depressant prescription in the year prior to delivery of the study child, and over three times as likely to have a prescription in the first trimester of pregnancy.

To further evaluate whether the observed association between prenatal SSRI exposure and ASD risk could be attributed to SSRI treatment rather than to the women's depression or anxiety for which she was prescribed the medication, researchers conducted an analysis of the subgroup of women with a history of mental health disorders in the year before delivery. Risk of ASD associated with SSRI use anytime during this year remained somewhat elevated in this subgroup, but did not reach statistical significance.

To assess the possibility that women prescribed SSRIs during the year before delivery had a more severe underlying condition that accounts for the finding, researchers examined indicators of severity of psychiatric illness. Among these women, the proportion with previous psychiatric hospitalizations and the mean number of hospitalizations was not significantly different in cases compared to controls.

Prior studies have indicated that abnormalities in serotonin levels and serotonin pathways may play a role in autism. Collectively these studies suggest the possibility that prenatal SSRI exposure may operate directly on the developing brain, perhaps selectively in fetuses with abnormalities in serotonin-related genes, explained Croen. She adds that physiologic changes related to maternal stress or depression during pregnancy, in combination with SSRI exposure, may contribute to changes in fetal brain development leading to later-diagnosed ASD.

Gum disease can increase the time it takes to become pregnant

For the first time, fertility experts have shown that, from the time that a woman starts trying to conceive, poor oral health can have a significant effect on the time to pregnancy.

Professor Roger Hart told the annual meeting of the European Society of Human Reproduction and Embryology that the negative effect of gum disease on conception was of the same order of magnitude as the effect of obesity.

Periodontal (gum) disease is a chronic, infectious and inflammatory disease of the gums and supporting tissues. It is caused by the normal bacteria that exist in everyone's mouths, which, if unchecked, can create inflammation around the tooth; the gum starts to pull away from the tooth, creating spaces (periodontal pockets) that become infected. The inflammation sets off a cascade of tissue-destructive events that can pass into the circulation. As a result, periodontal disease has been associated with heart disease, type 2 diabetes, respiratory and kidney disease, and problems in pregnancy such as miscarriage and premature birth. Around 10% of the population is believed to have severe periodontal disease. Regular brushing and flossing of teeth is the best way of preventing it.

Prof Hart, who is Professor of Reproductive Medicine at the University of Western Australia (Perth, Australia) and Medical Director of Fertility Specialists of Western Australia, said: "Until now, there have been no published studies that investigate whether gum disease can affect a woman's chance of conceiving, so this is the first report to suggest that gum disease might be one of several factors that could be modified to improve the chances of a pregnancy."

The researchers followed a group 3737 pregnant women, who were taking part in a Western Australian study called the SMILE study, and they analysed information on pregnancy planning and pregnancy outcomes for 3416 of them.

They found that women with gum disease took an average of just over seven months to become pregnant – two months longer than the average of five months that it took women without gum disease to conceive.

In addition, non-Caucasian women with gum disease were more likely to take over a year to become pregnant compared to those without gum disease: their increased risk of later conception was 13.9% compared to 6.2% for women without gum disease. Caucasian women with gum disease also tended to take longer to conceive than those who were disease-free but the difference was not statistically significant (8.6% of Caucasian women with gum disease took over one year to conceive and 6.2% of women with gum disease).

Information on time to conception was available for 1,956 women, and of, these, 146 women took longer than 12 months to conceive – an indicator of impaired fertility. They were more likely to be older, non-Caucasian, to smoke and to have a body mass index over 25 kg/m2. Out of the 3416 women, 1014 (26%) had periodontal disease.

Prof Hart said: "Our data suggest that the presence of periodontal disease is a modifiable risk factor, which can increase a woman's time to conception, particularly for non-Caucasians. It exerts a negative influence on fertility that is of the same order of magnitude as obesity. This study also confirms other, known negative influences upon time to conception for a woman; these include being over 35 years of age, being overweight or obese, and being a smoker. There was no correlation between the time it took to become pregnant and the socio-economic status of the woman.

"All women about to plan for a family should be encouraged to see their general practitioner to ensure that they are as healthy as possible before trying to conceive and so that they can be given appropriate lifestyle advice with respect to weight loss, diet and assistance with stopping smoking and drinking, plus the commencement of folic acid supplements. Additionally, it now appears that all women should also be encouraged to see their dentist to have any gum disease treated before trying to conceive. It is easily treated, usually involving no more than four dental visits.

"The SMILE study was one of the three largest randomised controlled trials performed in Western Australia. It showed conclusively that although treatment of periodontal disease does not prevent pre-term birth in any ethnic group, the treatment itself does not have any harmful effect on the mother or foetus during pregnancy*."

Prof Hart said that the reason why pregnancies in non-Caucasian women were more affected by gum disease could be because these women appeared to have a higher level of inflammatory response to the condition.

Giving up smoking averts adverse birth outcomes


Results from a study of over 50 000 pregnancies revealed that women who gave up smoking when their pregnancy was confirmed gave birth to babies with a similar birthweight to those born to mothers who had never smoked, Professor Nick Macklon, from the Department of Obstetrics and Gynaecology, University of Southampton, UK, told the annual conference of the European Society of Human Reproduction and Embryology today (Wednesday).

Low birthweight is the most common negative outcome of smoking during pregnancy, but foetuses exposed to maternal smoking are also at risk of premature birth and the associated problem of brain damage, as well as congenital abnormalities such as cleft lip. Mothers who smoke are encouraged to stop smoking when they become pregnant, but to date there was little evidence that giving up at this late stage could have a positive effect on birthweight.

Professor Macklon and colleagues decided to investigate this question by studying clinical, lifestyle, and socioeconomic data collected from pregnancies registered at the Southampton University Medical Centre between 2002 and 2010. They identified seven groups of women – non-smokers, those who had stopped more than a year prior to conceiving, those who had stopped less than a year prior to conceiving, smokers who stopped once the pregnancy was confirmed, and those who continued to smoke up to 10 a day, between 10 and 20 a day, and more than 20 a day. They proceeded to compare smoking behaviour in the mothers with perinatal outcomes in the children.

After correcting for gestational age, maternal age, BMI and socioeconomic class, all of which are known to affect birth outcomes, the researchers found that those babies whose mothers had stopped smoking in the periconceptional period – around the time of getting pregnant or as soon as the pregnancy was confirmed – had a significantly higher birthweight.

"Not only was birthweight much better in this group than it was in the groups where the mothers had continued to smoke, but we also found that the babies reached the same gestational age and head circumference as those born to women who had never smoked," said Professor Macklon. "While a recent study has shown that the rate of pre-term and small-for-gestational-age births can be reduced by stopping smoking before the 15th week of pregnancy, our research goes much further. We can now give couples hard evidence that making the effort to stop smoking in the periconceptional period will be beneficial for their baby."

Although there is now overwhelming evidence that maternal smoking during pregnancy is damaging to the foetus, some mothers continue to smoke because they like the idea of giving birth to a smaller baby. "It is important that people who believe that a smaller baby means an easier birth take into account the increased risks of complicated deliveries in smokers," said Professor Macklon, "as well as the risk of disease later in life which goes with low birthweight. Smoking during pregnancy is not just bad for the mother and baby, but for the adult it will grow into."

In addition to this, smoking can also make it more difficult for a woman to get pregnant and carry a baby to term. Because of their faster ovarian ageing, women smokers have higher rates of infertility than non-smokers and will undergo an earlier than normal menopause. They are also are more likely to have miscarriages.

"In future we would like to look at the impact of stopping smoking prior to fertility treatments, as we believe that this could bring about improvements to fertility outcomes," said Professor Macklon. "But for now we hope that our research will provide additional encouragement to mothers-to-be to give up cigarettes."

Wednesday, June 29, 2011

Vitamin D supplements safe for healthy pregnant women

Use of vitamin D supplements during pregnancy has long been a matter of concern but now researchers writing in the Journal of Bone and Mineral Research report that even a high supplementation amount in healthy pregnant women was safe and effective in raising circulating vitamin D to a level thought by some to be optimal. The study also found no adverse effects of vitamin D supplementation, even at the highest amount, in women or their newborns.

The research team, led by Dr. Bruce Hollis from the Medical University of South Carolina in Charleston, used a randomized controlled trial with healthy expectant mothers to discover how varying dosages of daily supplements could safely sustain a circulating vitamin D level of at least 32 nanograms per milliliter.

"Vitamin D supplementation during pregnancy remains controversial largely due to severe misconceptions about the potential harm it may cause to the fetus," said Dr Hollis. "Surprisingly the scientific debate has made little progress since Dr. Gilbert Forbes made a recommendation of 200 IU (international units) per day in 1963, which was based on a hunch."

While the threat of vitamin D during pregnancy has remained little known, it has been established that the vitamin plays a role in homeostasis, the body's internal regulation, during pregnancy and that a deficiency can effect immune, pancreatic and cardiovascular systems.

Dr Hollis' team monitored the pregnancies of 350 women, from a variety of ethnic and socio-economic backgrounds, who were all between 12 and 16 weeks into gestation. The women were randomly assigned to one of three groups. One group received 400 IU of vitamin D per day, the second group received 2,000 IU per day and the third received 4,000 IU daily.

The team found that women who received the highest level of supplementation (4,000 IU per day) were more likely to achieve and sustain the desired level of circulating levels of vitamin D throughout their pregnancy. Moreover, the researchers found that pregnant women who received lower levels of vitamin D supplementation did not attain the threshold circulating level of the vitamin.

"In our study subjects, a daily dosage of up to 4,000 IU of vitamin D was required to sustain normal metabolism in pregnant women," concluded Dr Hollis. "Furthermore, following decades of speculation into its safety our research has demonstrated vitamin D supplementation to be both safe and effective."

Wednesday, June 22, 2011

Smoking During Pregnancy Lowers Levels of 'Good' HDL Cholesterol in Children

Researchers in Australia have discovered that mothers who smoke during pregnancy are causing developmental changes to their unborn babies that lead to them having lower levels of the type of cholesterol that is known to protect against heart disease in later life -- high-density lipoprotein (HDL) cholesterol.

The research, published online in the European Heart Journal, showed that, by the age of eight years, children born to mothers who smoked while they were pregnant had HDL cholesterol levels of about 1.3 millimoles per litre (mmol/L), compared to the more normal level of 1.5 mmol/L in children born to mothers who had not smoked. After adjustments for various factors that might affect the result, the difference attributable to mothers' smoking was about 0.15 mmol/L. The researchers found that this effect was independent of whether the children had been exposed to other people's smoke after birth, suggesting that prenatal exposure had the most impact on the children's subsequent development.

David Celermajer, Scandrett Professor of Cardiology at the University of Sydney, Australia, who led the study, said: "Our results suggest that maternal smoking 'imprints' an unhealthy set of characteristics on children while they are developing in the womb, which may well predispose them to later heart attack and stroke. This imprinting seems to last for at least eight years and probably a lot longer."

Although cigarette smoking during and after pregnancy is known to be linked to a range of childhood health problems, including behavioural and neurocognitive problems and sudden infant death, until now it has been unclear what effect prenatal exposure to cigarette smoke had on the risk of future cardiovascular disease.

Prof Celermajer and his colleagues decided to examine the effects of maternal smoking during pregnancy on the thickness of the arterial wall and the levels of lipoproteins in a group of 405 healthy eight-year-olds, born between 1997 and 1999, who had been enrolled before birth into a randomised controlled trial that was investigating asthma and allergic diseases. The researchers collected data before the children were born and as they grew up, including information on mothers' smoking habits before and after pregnancy, the children's exposure to passive smoking, and measurements of height, weight, waist circumference and blood pressure. They used ultrasound scans to measure the arterial wall thickness and, in 328 children who agreed, they took blood in order to measure lipoprotein levels.

Although there was no effect on the thickness of the children's arterial wall, Prof Celermajer found that there was an effect on levels of HDL cholesterol, which remained statistically significant after adjusting for a range of factors that might have been different in children born to mothers who smoked, such as post-natal smoke exposure, duration of breast feeding, physical inactivity and body mass index.

The researchers believe that the lower levels of HDL cholesterol at this age suggest there could be a serious impact on health in later life, as the children will probably continue to have low levels in adulthood. "Cholesterol levels tend to track from childhood to adulthood, and studies have shown that for every 0.025mmol/L increase in HDL levels, there is an approximately 2-3% reduction in the risk of coronary heart disease. If we extrapolate this, we can suggest that the difference of 0.15mmol/L between children of smoking mothers versus non-smoking mothers might result in a 10-15% higher risk for coronary disease in the children of smoking mothers. This is an approximation only, but the best one we have," said Prof Celermajer.

The researchers point out that the prevalence of smoking during pregnancy is still high, at around 15% in many Western countries. Therefore, their findings may be important for informing population-based strategies for preventing heart disease in later life, especially as HDL cholesterol plays an important role in protecting against atherosclerosis -- a condition in which fatty materials collect along the walls of arteries, thickening and eventually blocking them, leading to problems such as angina and heart attacks.

"Children born to mothers who have smoked during pregnancy will need to be watched particularly carefully for other coronary risk factors, like high blood pressure, high LDL, 'bad' cholesterol levels, and especially cigarette smoking themselves," said Prof Celermajer.

"The only ways to increase HDL levels are regular exercise and with the use of certain medications such as Niacin. We will have to do long-term follow-up to see if these particular children continue to have lower HDL cholesterol levels than normal, but one should presume that this risk factor might indeed be persistent."

The mechanism whereby maternal smoking during pregnancy lowers HDL cholesterol in children is unknown. "One of the advantages of studying this in eight-year-old children is that the usual factors that drive down HDL cholesterol, such as obesity and diabetes, are absent, and so we can infer a more or less direct effect of smoking on HDL levels, rather than one mediated through changes in body composition or vulnerability to diabetes," concluded Prof Celermajer.

Monday, June 13, 2011

Sleep apnea increases risk of pregnancy

Pregnant women with severe sleep apnea may have an increased risk of gestational diabetes and early preterm birth

Sleep apnea is associated with an increased risk of adverse pregnancy outcomes, suggests a research abstract that will be presented Monday, June 13, in Minneapolis, Minn., at SLEEP 2011, the 25th Anniversary Meeting of the Associated Professional Sleep Societies LLC (APSS).

Results show that women with severe sleep apnea had the highest incidence of adverse pregnancy outcomes. This increased prevalence was principally driven by a higher incidence of gestational diabetes and early preterm birth.

The authors noted that sleep apnea has been associated with heart disease, metabolic syndrome and mortality in non-pregnant populations. However, few studies have examined the relationship between sleep apnea in pregnancy and adverse obstetrical outcomes.

"Our findings suggest that moderate to severe sleep-disordered breathing may be associated with adverse pregnancy outcomes, particularly gestational diabetes and preterm birth," said principal investigator Dr. Francesca L. Facco, assistant professor in the department of obstetrics and gynecology at Northwestern University in Chicago. "However, it is unclear if sleep-disordered breathing is a risk factor for adverse pregnancy outcomes independent of obesity."

According to the American Academy of Sleep Medicine, sleep apnea is a form of sleep-disordered breathing that involves partial reductions (hypopneas) and complete pauses (apneas) in breathing during sleep. The most common form of sleep apnea is obstructive sleep apnea, which occurs when the muscles relax during sleep, causing soft tissue in the back of the throat to collapse and block the upper airway. The breathing pauses that result can produce abrupt reductions in blood oxygen saturation and reduce blood flow to the brain. Most people with OSA snore loudly and frequently, and they often experience excessive daytime sleepiness.

Facco and colleagues searched a medical records database and identified 150 women who had received a sleep evaluation by overnight polysomnography and had given birth between January 2000 and June 2009. About 87 percent of the women were overweight or obese at delivery with a body mass index of 25 or more. Seventy-two percent of the women had undergone the sleep study within three years of their delivery. For women with more than one pregnancy during the study period, the first pregnancy with outcome information was selected for analysis.

Women with an apnea-hypopnea index of five to 14.9 breathing pauses per hour of sleep were considered to have mild to moderate sleep apnea, and those with an AHI of 15 or more were classified as having severe sleep apnea. The analysis assessed the associations between sleep apnea and three adverse pregnancy outcomes: pregnancy induced hypertension, gestational diabetes, and early preterm birth at 34 weeks or less.

Facco added that more research is needed to clarify how sleep apnea and obesity interact with maternal and neonatal health.

"Further studies, principally large prospective studies utilizing objective measures of sleep-disordered breathing, are needed to confirm this relationship, and to examine the interaction between sleep-disordered breathing and body mass index," said Facco. "If a relationship is confirmed, further studies would be needed to ascertain the role of treatment of sleep-disordered breathing in pregnancy."

The treatment of choice for obstructive sleep apnea is CPAP therapy, which provides a steady stream of air through a mask that is worn during sleep. This airflow keeps the airway open to prevent pauses in breathing and restore normal oxygen levels. Help for people with sleep apnea is available at more than 2,200 AASM-accredited sleep disorders centers across the U.S.

The SLEEP 2011 abstract supplement is available for download on the website of the journal Sleep at

Tuesday, June 7, 2011

Pregnant women can prevent excess weight gain with simple steps

A new study reports that a low-cost healthy lifestyle program, including self-weighing weekly or monthly, by pregnant women with pre-existing overweight can prevent them from gaining too much weight during early pregnancy. The researchers will present the results Sunday at The Endocrine Society's 93rd Annual Meeting in Boston.

"Preventing excess weight gain in pregnancy is essential to the health of all mothers and their babies and can be achieved by increasing awareness [of weight during pregnancy] and by simple health messages, behavior change strategies, and regular monitoring of weight gain," said lead author Catherine Lombard, PhD, of the Monash University School of Public Health and Preventive Medicine, Melbourne, Australia.

"This weight-management strategy has the potential to reduce pregnancy complications, such as gestational diabetes, and birth complications," Lombard said.

The clinical trial consisted of more than 200 overweight women, recruited from a hospital-based clinic, who were less than 15 weeks pregnant. All women were at high risk of developing gestational diabetes (pregnancy-related diabetes) because of their age, weight, ethnicity, previous gestational diabetes or a family history of diabetes. They were randomly assigned to the intervention group (106 women) or control group (99 women).

At 14 weeks of pregnancy, both groups received health information emphasizing making small, healthy changes to eating and physical activity, such as walking and eating more fruit and vegetables. The intervention group also received information about how much weight they should gain during pregnancy, an instruction to weigh themselves weekly or monthly and frequent reminders by text messaging. The control group received no instruction or reminders to self-weigh. Both groups received standard prenatal care.

Measures included weight, frequency of self-weighing, physical activity and food intake at the beginning of the study and at 28 weeks of pregnancy. This is the time that routine testing for gestational diabetes occurs, according to Lombard.

At 28 weeks regular self-weighing was associated with significantly less pregnancy weight gain for intervention participants than for the control participants—12.6 pounds versus 15.7 pounds, respectively. Women in both groups who did not self-weigh gained a similar amount of weight: an average of 15.2 pounds.

"We conclude," Lombard said, "that self-weighing keeps women focused on their behavior. When it is paired with a simple self-management intervention to prevent excess weight gain, it has a significant impact on weight gain in high-risk pregnancies."

Excessive pregnancy weight gain raises the risk of having a fat baby

Women who gain too much weight during pregnancy tend to have newborns with a high amount of body fat, regardless of the mother's weight before pregnancy, a new study finds. The results will be presented Tuesday at The Endocrine Society's 93rd Annual Meeting in Boston.

High fat at birth is a possible risk factor for childhood obesity, said the study's principal investigator, Jami Josefson, MD, a pediatric endocrinologist at Chicago's Children's Memorial Hospital and assistant professor at Northwestern University Feinberg School of Medicine.

"Previous studies have shown that children of mothers who gain too much weight during pregnancy are more likely to be overweight for their age," Josefson said. "However, not all these studies accounted for the mother's diabetes status during pregnancy, which is a known risk factor for offspring obesity."

The new study evaluated only pregnant women without gestational diabetes, therefore ruling out the chance that this disorder could account for their findings.

Josefson and her colleagues wanted to learn whether pregnant women who gain more than the recommended amount of weight have fat infants. Doctors, however, do not typically measure a newborn's body fat, she said. Many past studies that measured newborn body fat used an imprecise method, such as skin fold thickness, according to the authors' abstract.

This study used a new infant body composition system (Pea Pod) that employs an air-displacement technique, which Josefson said accurately and safely measures newborn body fat. This technique requires the infant to simply lie in a machine for two minutes, she said. Newborns in the study underwent measurements of length, weight and fat within 48 hours of birth.

Of the 56 mothers the researchers studied, 31 women were within guidelines for pregnancy weight gain, and 25 exceeded the guidelines. The Institute of Medicine recommends that women at a healthy weight before pregnancy gain 25 to 35 pounds while expecting a single baby; overweight women, 15 to 25 pounds; and obese women, 11 to 20 pounds.

Study subjects who were obese before pregnancy were more likely than healthy-weight women to exceed the weight-gain guidelines (70 percent versus 31 percent, respectively), the authors reported. Yet regardless of pre-pregnancy weight, women who put on more than the recommended weight gave birth to significantly fatter babies. Their newborns had 490 grams, or 17.5 ounces, of body fat, whereas newborns of women who stayed within the guidelines had 390 grams (13.9 ounces) of fat. This higher obesity risk existed even when birth weight was normal.

"Excessive weight gain during pregnancy, regardless of pre-pregnancy weight, is an important risk factor for newborn obesity," Josefson said. "More research is needed to determine if high amounts of fat at birth are associated with high amounts of fat in childhood."

Thursday, June 2, 2011

Maternal Smoking Causes Changes in Fetal DNA

Children whose mothers or grandmothers smoked during pregnancy are at increased risk of asthma in childhood, but the underlying causes of this are not well understood. Now a new study indicates changes in a process called DNA methylation that occurs before birth may be a root cause.

DNA methylation is a process that can alter a gene’s usual function. These altered genes can be passed along from parent to child. In this case, researchers observed DNA methylation-related changes in the AXL gene in children exposed to maternal smoking in utero. The AXL gene plays an important role in many human cancers and in immune response.

“We found that children exposed to maternal smoking in utero had a 2.3 percent increase in DNA methylation in AXL,” said Carrie Breton, ScD, assistant professor of preventive medicine at The Keck School of Medicine of the University of Southern California (USC) in Los Angeles.

“These results confirm results from a prior study and present compelling evidence that environmental exposure to tobacco smoke during pregnancy may alter DNA methylation levels."’

Using a detailed questionnaire, the researchers targeted the mothers and grandmothers of 173 children participating in the Early Asthma Risk Factors Study (EARS), a study within the larger California Children’s Health Study, and assessed their smoking habits during pregnancy. DNA samples collected from cheek cells of mothers and children were evaluated. Dr. Breton and her team found that DNA methylation of AXL was associated with in utero exposure to maternal smoking, and also found that grandmaternal smoking was not significantly associated with AXL methylation in either the mother or the child. The association between DNA methylation of AXL and in utero exposure to smoking was stronger in girls than in boys, she added.

Dr. Breton said the results of the study indicate the need for a greater understanding of the effects environmental factors have on epigenetic changes – that is, changes in gene function or expression that occur as the result of mechanisms other than changes to the underlying DNA sequence – and early development in general.

“Environmental exposures occurring in utero have the potential to affect DNA methylation patterns before birth,” she explained. “Imprinted genes appear to be particularly susceptible to these exposures since they come from one parent and only a single copy from one chromosome in DNA is active. Any environmentally-induced epigenetic changes will have greater impact on gene expression and function. In utero and early life exposures are likely to be important, given what we know about timing during development when epigenetic marks are established.”

Investigating the effects of environmental exposures on epigenetics is a largely unexplored area of research, and one that holds great promise for understanding biological mechanisms that underlie exposure-disease associations, she added.
“We are interested in further characterizing the pattern of epigenetic marks across this gene and whether there is a widespread response to both maternal smoking exposure and air pollution exposure in utero,” Dr. Breton said. “We hope to also evaluate timing of effects of exposure during trimester by increasing the number of samples we evaluated in a manner that will let us compare trimester-specific exposures.”