LINK BETWEEN PREPREGNANCY OBESITY AND LOWER CHILD TEST SCORES

Women who are obese before they become pregnant are at higher risk of having children with lower cognitive function - as measured by math and reading tests taken between ages 5 to 7 years - than are mothers with a healthy prepregnancy weight, new research suggests.

In this large observational study, prepregnancy obesity was associated, on average, with a three-point drop in reading scores and a two-point reduction in math scores on a commonly used test of children’s cognitive function.

Previous research has suggested that a woman’s prepregnancy obesity can have a negative effect on fetal organs, such as the heart, liver and pancreas. Because fetal development is rapid and sensitive to a mother’s physiological characteristics, Ohio State University researchers sought to find out whether a mother’s obesity also could affect the fetal brain.

“One way you measure the effects on the brain is by measuring cognition,” said Rika Tanda, lead author of the study and a doctoral candidate in nursing at Ohio State.

The research also supported findings in previous studies suggesting that several other conditions affect childhood cognition, including how stimulating the home environment is, family income and a mother’s education and cognitive skills.

“The new piece here is we have a measure associated with the fetus’s environment to add to that set of potential risk factors,” said Pamela Salsberry, senior author of the study and a professor of nursing at Ohio State. “If we have a good way to understand the risks each child is born with, we could tailor the post-birth environment in such a way that they could reach their maximum capabilities.”

The research appears online and is scheduled for future print publication in the Maternal and Child Health Journal.

The researchers used data from the National Longitudinal Survey of Youth (NLSY) 1979 Mother and Child Survey, a nationally representative sample of men and women who were 14-21 years old in December 1978. From that dataset, Tanda collected information on 3,412 children born to NLSY mothers who had been full-term births, were between 5 and almost 7 years old at the time of their interview and who had no diagnosed physical or cognition problems.

In addition to documenting a number of characteristics about the mothers and the family environment, the researchers gauged the children’s cognitive function based on their performance on Peabody Individual Achievement Test reading recognition and math assessments.

The researchers calculated the mothers’ body mass index (BMI) based on their reported heights and weights. More than half of mothers had normal BMIs before pregnancy, and 9.6 percent were obese, meaning they had a BMI of 30 or higher.

Controlling for all other variables, the analysis showed that maternal prepregnancy obesity was negatively associated with math and reading test scores. Children of obese women scored, on average, three points lower on reading and two points lower on math than did children of healthy-weight women. The mean reading score among all the children was 106.1 points and the mean math score was 99.9.

Though the score differences seem small, Tanda noted that these effects of prepregnancy obesity were equivalent to a seven-year decrease in the mothers’ education and significantly lower family income, two other known risk factors that negatively affect childhood cognitive function.

Tanda said clinicians could use these findings to help encourage women patients of childbearing age to maintain a healthy weight, especially if they plan to get pregnant.

“This is a large population study, so at the individual level we can’t say that one person’s decision to change her weight will change her child’s outcome,” she said. “But these findings suggest that children born to women who are obese before pregnancy might need extra support.”

Added Salsberry, “It’s not only for their child’s sake. It’s also important for the health of the mother. But it is important to understand that maternal obesity during pregnancy could have implications for their children as well.”

“If we have a good way to understand the risks each child is born with, we could tailor the post-birth environment in such a way that they could reach their maximum capabilities.”

Without actual measures of women’s and fetuses’ insulin levels, inflammation and blood sugar readings, scientists can’t say for sure how prepregnancy obesity might affect the fetal brain. But previous studies have suggested that a mother’s impaired metabolic processes affect the fetal brain cell growth and formation of synapses.

The researchers also noted that obesity doesn’t automatically equate to unhealthy.

“There may be two obese moms that in fact have very different metabolic profiles. For the purposes of this study, her weight is a stand-in for biological data that we would like to have but don’t,” Salsberry said.

Socioeconomic data from the study supported previous findings that several post-birth conditions can have a positive association with higher children’s test scores. These include a stimulating home environment with plenty of books, a safe play environment and frequent family meals; higher family income; and higher maternal education levels and cognitive function. Girls and first-born children also performed better on the math and reading tests than did boys and younger siblings.

With all these data combined, Tanda said, the study also reveals how health disparities can have long-lasting effects.

“Young females who grow up poor, who have less access to healthy foods resulting in diets that are of poorer quality, are at higher risk of having children with disadvantages and repeating this cycle,” she said.

The researchers are continuing to examine additional influences on childhood cognition, including race, sex and age differences among mothers.

Prenatal choline may 'program' healthier babies

Pregnant women may have added incentive to bulk up on broccoli and eggs now that a Cornell University study has found increased maternal intake of the nutrient choline could decrease their children's chances of developing hypertension and diabetes later in life.

In a study led by Marie Caudill, associate professor of nutritional sciences, and graduate student Xinyin Jiang, a group of third-trimester pregnant women consumed 930 milligrams of choline, more than double the recommended 450 milligram daily intake. The result for their babies was 33 percent lower concentrations of cortisol – a hormone produced in response to stress that also increases blood sugar – compared to those from a control group of women who consumed about 480 milligrams of choline.

Caudill believes this happened because the choline changed the expression patterns of genes involved in cortisol production. The work, published online this week in The Journal of the Federation of American Societies for Experimental Biology, is the first human study to suggest a role for choline in the "programming" of key biological processes in the baby.

"The study findings raise the exciting possibility that a higher maternal choline intake may counter some of the adverse effects of prenatal stress on behavioral, neuroendocrine and metabolic development in the offspring," Caudill said.

This could be especially useful for women experiencing anxiety and depression during their pregnancy, as well as conditions such as pre-eclampsia.

"A dampening of the baby's response to stress as a result of mom consuming extra choline during pregnancy would be expected to reduce the risk of stress-related diseases such as hypertension and type 2 diabetes throughout the life of the child," she added.

She said additional studies are needed to confirm the study findings and further explore long-term effects. Dietary sources of choline include egg yolks, beef, pork, chicken, milk, legumes and some vegetables. Most prenatal vitamin supplements do not include choline.

"We hope that our data will inform the development of choline intake recommendations for pregnant women that ensure optimal fetal development and reduce the risk of stress-related diseases," Caudill said.

Link Between Smoking During Pregnancy, Autism

Women who smoke in pregnancy may be more likely to have a child with high-functioning autism, such as Asperger’s Disorder, according to preliminary findings from a study by researchers involved in the U.S. autism surveillance program of the Centers for Disease Control and Prevention.

"It has long been known that autism is an umbrella term for a wide range of disorders that impair social and communication skills,” says Amy Kalkbrenner, assistant professor in the University of Wisconsin-Milwaukee’s Joseph J. Zilber School of Public Health, lead author of the study. “What we are seeing is that some disorders on the autism spectrum, more than others, may be influenced by a factor such as whether a mother smokes during pregnancy.” The study was published April 25 online by the journal Environmental Health Perspectives. Smoking during pregnancy is still common in the U.S. despite its known harmful impacts on babies. Kalkbrenner found that 13 percent of mothers whose children were included in the study had smoked during pregnancy.

Kalkbrenner and colleagues’ population-based study compared smoking data from birth certificates of thousands of children from 11 states to a database of children diagnosed with autism maintained by the CDC’s Autism and Developmental Disabilities Monitoring Network (ADDMN). Of the 633,989 children, born in 1992, 1994, 1996 and 1998, 3,315 were identified as having an autism spectrum disorder at age 8.

“The study doesn’t say for certain that smoking is a risk factor for autism,” Kalkbrenner says. “But it does say that if there is an association, it’s between smoking and certain types of autism,” implicating the disorders on the autism spectrum that are less severe and allow children to function at a higher level. That connection, she adds, needs further study. April is Autism Awareness Month, and several studies of possible links between environmental factors and autism are being published by Environmental Health Perspectives at the same time as Kalkbrenner’s study. “The CDC recently released data indicating that 1 in 88 children has an autism spectrum disorder, making such environmental studies even more timely,” says Kalkbrenner.

Because autism involves a broad spectrum of conditions and the interplay of genetics and environment is so complex, no one study can explain all the causes of autism, she adds. “The goal of this work is to help provide a piece of the puzzle. And in this we were successful.”

Dieting During Pregnancy Increases Risk Of Obesity And Diabetes For Offspring

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If you're expecting, this might make you feel a little better about reaching for that pint of ice cream: New research published online in the FASEB Journal suggests that twins, and babies of mothers who diet around the time of conception and in early pregnancy, may have an increased risk of obesity and type 2 diabetes throughout their lives. This study provides exciting insights into how behavior can lead to epigenetic changes in offspring related to obesity and disease.

"This study may provide a new understanding of why twins can develop diabetes," said Anne White, Ph.D., study author from the Faculty of Life Sciences at the University of Manchester in Manchester, UK. "It also suggests that dieting around the time a baby is conceived may increase the chance of the child becoming obese later in life."

To make this discovery, White and colleagues conducted experiments involving sheep to investigate twin pregnancies and the effects of altering nutrition around the time of conception and early pregnancy. Specifically, scientists examined the brain tissue of fetal sheep before birth and found that there were changes in the genes that control food intake and glucose levels that may lead to obesity and diabetes. These findings are unique because the differences found in the genes are not inherited changes in the DNA sequence, but rather, epigenetic changes with alterations in the structure of the DNA and its associated proteins, histones, which affects the way that genes can behave in later life.

"This study shows that expecting mothers have to walk a really fine line when it comes to diet and nutrition," said Gerald Weissmann, M.D., Editor-in-Chief of the FASEB Journal. "It also shows that epigenetics is the 'new genetics': both our DNA and the histones in which it is wrapped are susceptible to binge eating and dieting - we are what our mothers ate."

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Maternal obesity may influence brain development of premature infants

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Maternal obesity may contribute to cognitive impairment in extremely premature babies, according to a new study by researchers at Wake Forest Baptist Medical Center.

"Although in the past decade medical advances have improved the survival rate of babies born at less than seven months, they are still at very high risk for mental developmental delays compared with full-term infants," said Jennifer Helderman, M.D., assistant professor of pediatrics at Wake Forest Baptist and lead author of the study. "This study shows that obesity doesn't just affect the mother's health, but might also affect the development of the baby."

Published in the March issue of the journal Pediatrics, the study looked at 921 infants born before 28 weeks of gestation during 2002 to 2004 at 14 participating institutions. The researchers assessed the babies' placenta for infection and other abnormalities, interviewed the mothers and reviewed their medical records. At age 2, the children's cognitive skills were evaluated using the Mental Development Index (MDI) portion of the Bayley Scales of Infant Development, a commonly used measure.

The scientists found that both maternal obesity and lack of high school education were associated with impaired early cognitive function, as was pre-term thrombosis (blood clot) in the placenta.

"We weren't really surprised by the socioeconomic factors because it has been repeatedly shown that social disadvantage predicts worse infant outcomes," Helderman said. "However, obesity is of particular interest because it is becoming more prevalent and it is potentially modifiable during the pre-conception period and pregnancy."

Obesity has been linked to inflammation, and inflammation can damage the developing brain, Helderman said. What isn't known is if the obesity-related inflammation in the mother is transmitted to the fetus.

"Few studies have addressed prenatal risk factors of cognitive impairment for infants born this prematurely. The long-term goal is to use information from studies like ours to develop treatments that prevent cognitive impairment in extremely premature babies," Helderman said.

Helderman's colleague, Michael O'Shea, M.D., section head of neonatology at Wake Forest Baptist, is currently conducting a study that follows these same babies into mid-childhood to determine long-term cognitive problems.

More than 30,000 extremely premature babies are born each year in the United States.

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An Unlikely Bond: Prenatal Health and Dental Hygiene

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Oral health doesn’t always top the list of concerns that expectant mothers may have, but it certainly should. Proper dental health and control of oral disease can safeguard a mother’s health before and during pregnancy and reduces the transmission of bacteria from women to their children. According to numerous studies by the American Congress of Obstetricians and Gynecologists, many women do not seek, nor are instructed to seek, proper oral healthcare as part of their routine prenatal care.

“Caring for a pregnant mother’s teeth and gums should start before she becomes pregnant,” said Doron Kochman, DDS and Associate Clinical Professor of Pediatric Dentistry in the Department of Clinical Dentistry, at the University of Rochester Strong Memorial Hospital, and Eastman Dental Center in Rochester, NY. “Ideally, women who are planning to get pregnant should visit their dentists and have any necessary work done before the pregnancy. Mothers should continue to visit their dentists for routine prevention visits during their pregnancies.”

Due to the natural hormonal fluctuations during pregnancy, gums are more susceptible to swelling and inflammation. Because of this, bacteria can accumulate causing gum disease and further medical complications for both mother and baby. “We now know that the bacteria responsible for gum disease can also cause problems in places other than the mother’s mouth,” said Kochman. Periodontal disease increases the risk that bacteria will enter the bloodstream, causing potential infections in either mother or baby.

Studies have shown a link between periodontal disease in mothers and an increased chance of delivering premature or low birth weight babies. Because many pregnant women routinely experience swollen and bleeding gums after they brush, they may not recognize a true problem if it exists. Regular check-ups before and during pregnancy are highly recommended.

In addition to prematurity and low birth weight, other problems can result from oral health issues. Studies have suggested that periodontal disease can increase the risk for preeclampsia, a life-threatening disorder caused by high blood pressure which usually occurs mid-to-late pregnancy.

People with diabetes are also more likely to have periodontal disease. Diabetic mothers need to be vigilant about their blood glucose levels to protect their unborn children from fetal obesity, high blood insulin levels and blood disorders, among other conditions.

Furthermore, there is growing evidence that if a mother’s oral hygiene is less than optimal, her baby’s oral health can suffer. “An expectant mother’s diet and oral hygiene can affect her baby's teeth,” said Kochman. “The baby’s teeth start developing in the 5th or 6th week after conception. A mother's balanced diet during pregnancy provides the calcium, phosphorous, other minerals and vitamins needed for the baby’s teeth to form properly.”

Most dentists recommend the following tips for expectant moms:
• Brush at least twice a day to remove plaque buildup
• Floss regularly
• Avoid sugary snacks
• Eat a healthy, balanced diet
• Get regular dental exams (speak to your dentist to see what is right for you)

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Influenza vaccination of pregnant women helps their babies

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Vaccinating pregnant women against the influenza virus appears to have a significant positive effect on birth weight in babies, according to a study published in CMAJ (Canadian Medical Association Journal).

The study, a randomized controlled trial involving 340 healthy pregnant women in Bangladesh in the third trimester, looked at the effect of immunization with the influenza vaccine on babies born to vaccinated mothers. It was part of the Mother'sGift project looking at the safety and efficacy of pneumococcal and influenza vaccines in pregnant women in Bangladesh. The participants were divided into two groups, one with 170 women who received the influenza vaccine, and the second who received the pneumococcal vaccine as a control. Researchers compared the weight of babies born in two periods, one in which there was circulation of an influenza virus and one with limited circulation.

Babies that are small for their gestational age are at increased risk of health and other issues over their lives.

The researchers found that there were fewer babies who were small for their gestational age born to mothers in the influenza vaccine group when the virus was circulating, with 25.9% who were small compared with 44.8% in the control group. When the virus was dormant, the proportion of small-for-gestational-age births was similar in both groups. During the period with circulating influenza virus, the mean birth weight was 3178 g in the influenza vaccine group and 7% higher than 2978 g in the control group. The rate of premature births was lower in the influenza vaccine group as well.

"We found that immunization against influenza during pregnancy had a substantial effect on mean birth weight and the proportion of infants who were small for gestational age," writes Dr. Mark Steinhoff, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, with coauthors. "Our data suggest that the prevention of infection with seasonal influenza in pregnant women by vaccination can influence fetal growth," state the authors.

The researchers calculate that 10 maternal influenza vaccinations given year-round prevented one small-for-gestational-age birth, dropping to 6 vaccinations during the period in which the influenza virus was circulating.

The study was conducted by a team of US and Bangladeshi researchers from the Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Johns Hopkins University, Baltimore, Maryland; Emory University, Atlanta, Georgia; the International Centre for Diarrheal Disease Research, Dhaka, Bangladesh; and the Centers for Disease Control and Prevention, Atlanta, Georgia.

The authors suggest that if further research supports their findings, adding an influenza vaccine to routine vaccination programs during pregnancy could help children have a better start in life.

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