Tuesday, March 11, 2014
Just 2 weekly units may make a difference; middle class women most likely to drink more than this
Drinking alcohol during the first three months of pregnancy may heighten the risk of having a premature or unexpectedly small baby, suggests research published online in the Journal of Epidemiology and Community Health.
In the UK the Department of Health recommends that pregnant women and those trying to conceive should not drink alcohol at all and no more than 1-2 units a week.
Middle class women were most likely to drink more than this, the study found.
The researchers base their findings on responses to food frequency questionnaires by 1264 women at low risk of birth complications in Leeds. All the women were part of the Caffeine and Reproductive Health (CARE) study, looking into links between diet and birth outcomes.
The mums to be were asked how often they drank alcohol, and what type it was, at four time points: in the four weeks before conception; and in each of the subsequent three months (trimesters) throughout the pregnancy.
Alcohol consumption was significantly higher before conception and in the first three months of pregnancy than in the subsequent two trimesters, averaging 11, 4, and just under two units a week, respectively.
Over half (53%) of the women drank more than the recommended maximum two weekly units during the first trimester. And almost four out of 10 said they drank more than 10 units a week in the period leading up to conception.
Those who drank more than two units a week were more likely to be older, educated to degree level, of white ethnicity, and more likely to live in affluent areas.
Some 13% of the babies born were underweight, and 4.4% were smaller than would be expected; a similar proportion (4.3%) were born prematurely.
Drinking during the first three months of pregnancy was most strongly linked to these outcomes.
Women who drank more than the recommended two weekly units were twice as likely to give birth to an unexpectedly small or premature baby than women who abstained completely.
But even women who didn't exceed the maximum recommended alcohol intake during this period were still at increased risk of a premature birth, even after taking account of other influential factors.
Drinking during the period leading up to conception was also linked to a higher risk of restricted fetal growth, indicating that this may also be a critical period, suggest the authors.
"Our results highlight the need for endorsing the abstinence-only message, and further illuminate how timing of exposure is important in the association of alcohol with birth outcomes, with the first trimester being the most vulnerable period," they write.
Thursday, March 6, 2014
Exercising during pregnancy reduces excessive weight gain and the possibility of suffering from associated illnesses
These are the results of a study published in the journal Mayo Clinic Proceedings carried out by researchers from the University of Granada, Madrid Polytechnic University and the European University
The exercise plan designed managed to prevent excessive weight gain during pregnancy in 40% of the women studied. The risk of having a baby with macrosomia (inordinate weight of over 4 Kg in newly-born) can be reduced by up to 86% in obese or overweight women if they exercised during the pregnancy
Excessive weight gain during pregnancy increases the risk of suffering illnesses such as hypertension and gestational diabetes, or of having a premature birth or a birth by Caesarean; furthermore, it also has negative effects on the newly-born and increases the risk of infants being overweight by 30%.
Aware of the importance of preventing gestational weight gain, both in mother and child, researchers from the University of Granada, Madrid Polytechnic University and the European University carried out a study on the benefits of exercising during pregnancy to prevent weight gain, entitled “Supervised Exercise – Based Intervention to Prevent Excessive Gestational Weight Gain: A Randomized Controlled Trial”, which has been published in the journal Mayo Clinic Proceedings.
The research, which took place between 2007 and 2011, and in which 962 pregnant women took part, reveals that, in healthy women, moderate-intensity supervised exercise, begun immediately following the first prenatal consultation, avoids excessive weight gain on ending this period and reduces the risk of suffering from associated illnesses, such as gestational diabetes or hypertension.
Furthermore, the study shows that the benefits of exercise are greater in women of normal weight than in those that are overweight or obese, who can also benefit from exercise, but to a lesser extent.
Dr. Rubén Barakat, head researcher of the study and lecturer at the Madrid Polytechnic University, declares that “thanks to the joint work of professionals from the fields of Sports Science and Medicine, we have been able to demonstrate the importance of correct exercising habits, supervised and directed during the pregnancy. In this sense, there is still a lot to do, since we believe that the benefits of programmed physical excercise during pregnancy can even affect the infant’s first years of life. Recent scientific evidence allows us to consider this idea. For this, new studies are needed to research the influence of gestational exercise on maternal, fetal and child parameters; it would be a great mistake not to extend this type of research, using more extensive and ambitious clinical tests. This is only the tip of the iceberg”.
In turn, Dr. Jonatan Ruiz, main author of the article and a Ramón y Cajal researher at the Faculty of Sports Science of the University of Granada, underlines that “the benefits of regular physical activity during pregnancy and the post-natal period are the same well-known benefits that the general population obtain. Pregancy is an ideal time to change habits and to adopt a physically-active lifestyle during this period and for the rest of life”.
The researcher and professor of Exercise Pysiology at the European University, Alejandro Lucía, adds that “in general, the benefits of physical exercise are greatly neglected in current medicine and this type of studies helps to create more knowledge so that doctors will prescribe exercise that is personalized and in accordance with the conditions of each sector of the population”.
Lower weight gain
To carry out this study, the women were randomly divided into two equal groups. The first group, as well as carrying out the usual pregnancy healthcare instructions, took light-to-moderate aerobic exercise 3 times a week in sessions of 50-55 minutes, from weeks 9 to 39 of the pregnancy. The second group followed the usual recommendations for any pregnant woman.
The results of the study show that weight gain in the women who followed the exercise programme was less that in the women that did not; more specifically, the risk of gaining weight in excess of the recommendations of the American Institute of Medicine was 40% lower in the women who followed the regime of physical activity. To analyse the results, the researchers took into account data such as age of the mother, gestational age, studies and weight before pregnancy.
Likewise, even though that, in the case of the obese or overweight women, taking exercise 3 times a week has not been as efficient, there has been an 86% reduction in the risk of having a baby with macrosomia (inordinate weight of over 4 Kg in newly born).
The researchers state that, through this type of studies, “we wish to emphasize the importance of maintaining the health of pregnant women, as well as their children, by reaching an optimum weight; hence the importance of taking physical exercise”.
Pregnant women who eat a "prudent" diet rich in vegetables, fruits, whole grains and who drink water have a significantly reduced risk of preterm delivery, suggests a study published on bmj.com today.
A "traditional" dietary pattern of boiled potatoes, fish and cooked vegetables was also linked to a significantly lower risk.
Although these findings cannot establish causality, they support dietary advice to pregnant women to eat a balanced diet including vegetables, fruit, whole grains, and fish and to drink water.
Preterm delivery (before 37 weeks of pregnancy) is associated with significant short and long term ill-health and accounts for almost 75% of all newborn deaths.
Evidence shows that a mother's dietary habits can directly affect her unborn child, so researchers based in Sweden, Norway and Iceland set out to examine whether a link exists between maternal diet and preterm delivery.
Using data from the Norwegian Mother and Child Cohort Study, they analysed preterm births among 66,000 women between 2002 and 2008.
To be included, participants had to be free of diabetes, have delivered a live single baby, and completed a validated food frequency questionnaire on dietary habits during the first four to five months of pregnancy.
Factors that may have affected the results (known as confounding), including a mother's age, history of preterm delivery and education were taken into account. Preterm delivery was defined as delivery between 22 and <37 weeks of pregnancy.
The researchers identified three distinct dietary patterns, interpreted as "prudent" (vegetables, fruits, oils, water as a beverage, whole grain cereals, poultry, fibre rich bread), "Western" (salty and sweet snacks, white bread, desserts, processed meat products), and "traditional" (potatoes, fish, gravy, cooked vegetables, low fat milk).
Among the 66,000 pregnant women, preterm delivery occurred in 3,505 (5.3%) cases.
After adjusting for several confounding factors, the team found that an overall "prudent" dietary pattern was associated with a significantly reduced risk of preterm delivery, especially among women having their first baby, as well as spontaneous and late preterm delivery.
They also found a significantly reduced risk of preterm delivery for the "traditional" dietary pattern. However, the "Western" dietary pattern was not independently associated with preterm delivery.
This indicates that increasing the intake of foods associated with a prudent dietary pattern is more important than totally excluding processed food, fast food, junk food, and snacks, say the authors.
They stress that a direct (causal) link cannot be drawn from the results, but say the findings suggest that "diet matters for the risk of preterm delivery, which may reassure medical practitioners that the current dietary recommendations are sound but also inspire them to pay more attention to dietary counselling."
These findings are important, as prevention of preterm delivery is of major importance in modern obstetrics. They also indicate that preterm delivery might actually be modified by maternal diet, they conclude.
In an accompanying editorial, Professor Lucilla Poston at King's College London, says healthy eating in pregnancy is always a good idea.
She points to several studies that have proposed the benefit of a diet rich in fruit and/or vegetables in prevention of premature birth, and says health professionals "would therefore be well advised to reinforce the message that pregnant women eat a healthy diet."
Monday, February 24, 2014
Bottom Line: Children of women who used the pain reliever acetaminophen (paracetamol) during pregnancy appear to be at higher risk for attention-deficit/hyperactivity disorder (ADHD)-like behavioral problems and hyperkinetic disorders (HKDs, a severe form of ADHD).
Author: Zeyan Liew, M.P.H., of the University of California, Los Angeles, and colleagues.
Background: Acetaminophen is the most commonly used medication for pain and fever during pregnancy. But some recent studies have suggested that acetaminophen has effects on sex and other hormones, which can in turn affect neurodevelopment and cause behavioral dysfunction.
How the Study Was Conducted: The authors studied 64,322 children and mothers in the Danish National Birth Cohort (1996-2002). Parents reported behavioral problems on a questionnaire, and HKD diagnoses and ADHD medication prescriptions were collected from Danish registries.
Results: More than half of the mothers reported using acetaminophen while pregnant. The use of acetaminophen during pregnancy appeared to be associated with a higher risk of HKD diagnosis, of using ADHD medications or of having ADHD-like behaviors at age 7 years. The risk increased when mothers used acetaminophen in more than one trimester during pregnancy.
Conclusion: "Maternal acetaminophen use during pregnancy is associated with a higher risk for HKDs and ADHD-like behaviors in children. Because the exposure and outcomes are frequent, these results are of public health relevance but further investigations are needed."
Editorial: An Interesting Observed Association
In a related editorial, Miriam Cooper, M.R.C.Psych, M.Sc., of Cardiff University School of Medicine, Wales, and colleagues write: "An interesting new study in this issue of the journal has found preliminary evidence that prenatal exposure to a drug considered safe in pregnancy (acetaminophen or paracetamol) may be associated with ADHD in childhood."
"Indeed, causation cannot be inferred from the present observed assocaitions, and Liew et al are right to point out that a replication of their study is needed," they continue.
"In summary, findings from this study should be interpreted cautiously and should not change practice. However, they underline the importance of not taking a drug's safety during pregnancy for granted, and they provide a platform from which to conduct further related analyses exploring a potential relationship between acetaminophen use and altered neurodevelopment," the editorial concludes.
Tuesday, January 7, 2014
Children are likely to have stronger muscles if their mothers had a higher level of vitamin D in their body during pregnancy, according to new research from the Medical Research Council Lifecourse Epidemiology Unit (MRC LEU) at the University of Southampton.
Low vitamin D status has been linked to reduced muscle strength in adults and children, but little is known about how variation in a mother's status during pregnancy affects her child.
Low vitamin D concentrations are common among young women in the UK, and although women are recommended to take an additional 10μg/day of vitamin D in pregnancy, supplementation is often not taken up.
In the research, published in the January edition of the Journal of Clinical Endocrinology and Metabolism, vitamin D levels were measured in 678 mothers in the later stages of pregnancy.
When the children were four years old, grip strength and muscle mass were measured. Results showed that the higher the levels of vitamin D in the mother, the higher the grip strength of the child, with an additional, but less pronounced association between mother's vitamin D and child's muscle mass.
Lead researcher Dr Nicholas Harvey, Senior Lecturer at the MRC LEU at the University of Southampton, comments: "These associations between maternal vitamin D and offspring muscle strength may well have consequences for later health; muscle strength peaks in young adulthood before declining in older age and low grip strength in adulthood has been associated with poor health outcomes including diabetes, falls and fractures. It is likely that the greater muscle strength observed at four years of age in children born to mothers with higher vitamin D levels will track into adulthood, and so potentially help to reduce the burden of illness associated with loss of muscle mass in old age."
The 678 women who took part in the study are part of the Southampton Women's Survey, one of the largest and best characterised such studies globally.
Professor Cyrus Cooper, Professor of Rheumatology and Director of the MRC LEU at the University of Southampton, who oversaw this work, added: "This study forms part of a larger programme of research at the MRC Lifecourse Epidemiology Unit and University of Southampton in which we are seeking to understand how factors such as diet and lifestyle in the mother during pregnancy influence a child's body composition and bone development. This work should help us to design interventions aimed at optimising body composition in childhood and later adulthood and thus improve the health of future generations."
Monday, December 23, 2013
Peanut and tree nut allergy incidence lower among children whose mothers ate them during pregnancy
Women need not fear that eating peanuts during pregnancy could cause their child to develop a peanut allergy, according to a new study from Boston Children's Hospital published online Dec. 23 in JAMA Pediatrics.
"Our study showed increased peanut consumption by pregnant mothers who weren't nut allergic was associated with lower risk of peanut allergy in their offspring," says the study's senior author Michael Young, MD, of Boston Children's Division of Allergy and Immunology. "Assuming she isn't allergic to peanuts, there's no reason for a woman to avoid peanuts during pregnancy."
Previously, women had been advised to avoid highly allergenic foods such as peanuts and tree nuts during pregnancy and while nursing, and that their children should avoid peanuts until 3 years of age. The goal of these recommendations, despite a lack of supporting research, was to minimize early allergen exposure and sensitization, thereby reducing the risk of developing childhood peanut allergy. The American Academy of Pediatrics (AAP) endorsed these recommendations in 2000. However, from 1997 to 2007, the number of peanut allergy cases in the U.S. tripled, leading the medical community to reexamine its recommendations. Based on the lack of evidence supporting early dietary avoidance, the AAP rescinded the recommendation in 2008.
"No one can say for sure if the avoidance recommendation for peanuts was related to the rising number of peanut allergies seen in the late 1990s and early 2000s, but one thing is certain: it did not stop the increase," Young says. "It was clear that a new approach was needed, opening the door for new research."
To further define the relationship between maternal diet and the development of food allergy in offspring, Young and his team analyzed large amounts of data provided by the Growing Up Today Study (GUTS). Examining the records of 8,205 children, the researchers positively identified 140 cases of peanut or tree nut allergies. They then examined the diets of each child's mother—specifically, peanut and nut consumption—during the peri-pregnancy period and compared them with the dietary habits of pregnant women whose children did not develop a peanut allergy.
Young and team found that the rate of peanut allergy was significantly lower among children in the study whose mothers ate peanuts during the peri-pregnancy period. Although this is a substantial finding, the data demonstrate only an association between maternal diet and the risk of peanut allergy in children.
"The data are not strong enough to prove a cause-and-effect relationship. Therefore, we can't say with certainty that eating more peanuts during pregnancy will prevent peanut allergy in children. But we can say that peanut consumption during pregnancy doesn't cause peanut allergy in children," Young says. "By linking maternal peanut consumption to reduced allergy risk we are providing new data to support the hypothesis that early allergen exposure increases tolerance and reduces risk of childhood food allergy."
Thursday, December 19, 2013
One-quarter of US women gain an inadequate amount of weight during pregnancy, University of Maryland School of Public Health study shows
Women who do not gain enough weight during pregnancy are at increased risk of losing their baby in its first year of life, according to a new study by researchers in the University of Maryland School of Public Health (UMD SPH). This study examined the relationship between gestational weight gain, mothers' body mass index (BMI) before and during pregnancy, and infant mortality rates. One-quarter of the more than 159,000 women in the study gained too little weight during pregnancy, and these mothers were more likely to give birth to babies who died in infancy than the women who gained a normal or even excessive amount of weight during pregnancy. The study is published in the American Journal of Public Health. It was conducted by Dr. Regina Davis, associate executive director of the American Public Health Association, Dr. Sandra Hofferth, professor, and Dr. Edmond Shenassa, associate professor. All three are affiliated with the UMD SPH Maternal and Child Health Program, Department of Family Science, and Hofferth and Shenassa are faculty associates of the Maryland Population Research Center.
"Our study showed that gaining too little weight during pregnancy is a risk factor for infant mortality for all but the heaviest women," explained Dr. Davis. Gaining more weight than recommended was not a risk factor for infant mortality but may be related to subsequent maternal health problems. "It is important that childbearing women have pregnancy weight gain goals that are specific to their individual BMI," added Dr. Hofferth, the study's senior author.
According to guidelines published by the Institute of Medicine (IOM), underweight women should gain between 28 and 40 pounds during pregnancy, while normal weight women are expected to gain 25-35 pounds, overweight women 15-25 pounds, and obese women 11-20 pounds. Results from this study showed that only about a third of women gained an amount of weight that was within the recommended guidelines for their body size. Nearly 25% of the women in the study gained an inadequate amount of weight, while another 41% gained too much.
Davis, Hofferth, and Shenassa analyzed data collected from 159,244 mothers who gave birth to live, single babies between 2004 and 2008 in order to determine whether there was a link between gestational weight gain (GWG), mothers' body mass index (BMI), and infant mortality. The women in the study responded to telephone or written questionnaires within nine months after their babies' birth, and their information was recorded in the Pregnancy Risk Assessment Monitoring System (PRAMS) for use by future researchers. The study team analyzed the PRAMS data to learn whether mothers' BMI before and during pregnancy might alter the influence of GWG on infant mortality.
Infant mortality risks in the study sample were 3.9% among infants of mothers who gained an inadequate amount of weight during pregnancy, 1.2% among infants of mothers who gained an adequate amount of weight, and .7% among mothers who gained more than the recommended amount. Mothers' pre-pregnancy BMI was also a key factor in infant survival. Mothers who were underweight before pregnancy and gained too little weight during pregnancy had six times the normal rate of infant mortality. Even among overweight women, inadequate weight gain was associated with a two-fold elevation in the risk of mortality. Only children born to obese women were protected from the effects of inadequate weight gain. In contrast, gaining more than the recommended amount of weight was not associated with risk to the infant among mothers in any weight category. Obese mothers who gained an excessive amount of weight actually had a 49% reduced likelihood of infant death.
This study confirms that only about a third of women in the US gain weight during pregnancy that is within the recommended range. In order to improve the likelihood of healthy outcomes for mothers and infants, healthcare providers should provide childbearing women with gestational weight gain goals that are specific to their individual BMI. Pregnant women can help ensure the health of their infants by monitoring their weight gain, eating an appropriate amount of healthy foods, and engaging in reasonable physical activity.