Pregnancy diets: New findings should “guide new recommendations on obesity during pregnancy”

26 Sep 2019 --- Obese pregnant women do not need to add any calories to their daily diet to gain the recommended five to nine kilograms, as this may cause health issues for both mother and baby. This is according to a new study from Louisiana State University’s (LSU) Pennington Biomedical Research Center. Current guidelines suggest a 200 to 300 calorie increase during the second and third trimester, which the new study says should not apply to obese mothers. Such guidelines were not based on research involving actual obese pregnant women, note the researchers, while they highlight that their findings mark the first dietary intake recommendations for pregnant women with obesity, based on a study involving such subjects.

“What happens during pregnancy helps determine the future health of mothers and their children,” says Dr. Leanne Redman, Director of Pennington Biomedical’s Reproductive Endocrinology and Women’s Health Laboratory. “Pregnant women who gain an unhealthy amount of weight face a higher risk of health issues, including Type 2 diabetes and cardiovascular disease (CVD), and so do their babies. These risks are even higher for women with obesity.”

Published the Journal of Clinical Investigation, the new study is significant as it opposes longstanding calorie consumption guidelines for pregnant women with obesity. The National Academy of Medicine and the American College of Obstetricians and Gynecologists recommend that pregnant women with obesity add 200 to 300 calories – the number of calories in a crème-filled donut – to their daily diet during the second and third trimester. Doing so, according to the academy, will help pregnant women with obesity limit their total weight gain to the recommended five to nine kilograms.

However, the current calorie intake recommendation is based on research in women without obesity. Studies have consistently shown that two-thirds of women with obesity gain more than the recommended amount of weight. In addition, studies of more than 6,300 participants show that lifestyle interventions for pregnant women with obesity – improving diet and increasing physical activity – have been of little help in preventing excess weight gain.

The researchers also note that guidelines should advise improving the quality of the diet without adding more calories.The new study from Pennington Biomedical followed 72 pregnant women with obesity. The researchers found that adding the recommended 200 to 300 calories per day produced gestational weight gain in excess of the academy recommendations. 

The study includes a commentary titled Time to Change Weight Gain Recommendations for Pregnant Women with Obesity by Dr. Sarah Comstock of Michigan State University. Dr. Comstock studies the impact of maternal obesity on infant microbiota and immune development. In the article, Dr. Comstock says the results of Pennington Biomedical’s study should guide new recommendations on obesity during pregnancy.

The researchers also note that guidelines should advise improving the quality of the diet without adding more calories.

Pregnancy risks linked to obesity
Previously, researchers from Pennington Biomedical also found that conventional ways to prevent gestational diabetes mellitus are ineffective and its appearance possibly depends on each individual’s health. The results found that moms-to-be who ate healthier and less, and increased their physical activity, developed gestational diabetes at about the same rates as women who didn't follow the same lifestyle. The researchers now believe there may be different types of gestational diabetes that warrant different approaches to treatment and prevention.

Furthermore, researchers from Queen Mary University and the University of Warwick conducted a study on the health effects of a Mediterranean-style diet on high-risk, multi-ethnic, inner-city pregnant women. Health benefits during pregnancy such as weight gain reduction and a lower risk of gestational diabetes may be the result of following such a diet, they found. Because a quarter of mothers enter pregnancy with pre-existing obesity, chronic hypertension or raised lipid levels, the study may offer a means for pregnant women to prevent antenatal health risks.

Lastly, another study found that obesity and a high-fat, high-sugar diet during pregnancy may predispose children to obesity. The study, published in The Journal of Physiology, found that such conditions create a “fatty liver” in the fetus. The observations may explain why children of obese mothers live shorter lives than the offspring of normal weight mothers. “Fatty Livers” can lead to very troubling issues including later life obesity, cancers, and metabolic and cardiovascular problems.

Edited by Kristiana Lalou