Normal Weight Moms Had Healthier Babies

Obesity or overweight in pregnant women may be tied to higher risk of infant health problems

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Being healthy doesn't just benefit you — it may benefit your child, too. Mothers-to-be who maintain a healthy weight may boost their child's health as well.

For pregnant women, being too heavy may bring health troubles to their babies. A new study found that infants born to women who were overweight or obese faced more health risks than those born to women who had a normal weight.

For women who struggle with their weight, the American Pregnancy Association says many overweight and obese women deliver happy, healthy babies with proper medical care, screening for pregnancy complications and a healthy diet.

"Ideally, overweight or obese women of childbearing age should be encouraged to lose weight before becoming pregnant," wrote Katrine Mari Owe, PhD, with the Norwegian National Advisory Unit on Women’s Health in the Department of Obstetrics and Gynecology at Oslo University Hospital in Norway.

Dr. Owe provided editorial commentary on the current study conducted by Stefan Johansson, PhD, consultant neonatologist with the Clinical Epidemiology Unit in the Department of Medicine at Karolinska University Hospital in Sweden, and fellow researchers.

Andre Hall, MD, an OB-GYN at Birth and Women's Care, PA in Fayetteville, NC, supported Dr. Owe's statement.

"I recommend that women lose weight to reach their ideal body weight or a body mass index of 25 prior to pregnancy," said Dr. Hall, who was not involved with this research. "The reality, however, is that this is not attainable for many women. Therefore, many patients who are obese and get pregnant must deal with the potential problems that are related to that weight. If a patient is obese and she gets pregnant, we recommend eating a healthy diet, regular exercise, and maintaing regular prenatal visits in order to monitor the growth and development of her baby."

For their study, Dr. Johansson and colleagues reviewed more than 1.8 million births recorded in the Swedish Medical Birth Register from 1992 to 2010.

They found that babies of women who were a healthy weight in early pregnancy were less likely to die than those of women who had an unhealthy weight. The rate of death was 2.4 per 1,000 among normal-weight women but rose to 5.8 per 1,000 among women with the highest level of obesity.

Normal weight was measured as a body mass index (BMI) of 18.5 to 24.9. Overweight was a BMI of 25 to 29.9. Obesity was a BMI of 30 or higher. BMI is a measure of body fat based on height and weight. Obese women in this study were evaluated in three levels: those with a BMI of 30 to 34.9, those with a BMI of 35 to 39.9, and those with a BMI of 40 or higher.

Infant mortality risk increased only modestly for overweight and mildly obese mothers-to-be compared to those of normal weight, Dr. Johansson and team noted. Pregnant women with BMIs of 35 or higher, however, had infant mortality rates that were more than double those of normal-weight women.

These researchers estimated that about 11 percent of the infant deaths in the study were because of maternal overweight and obesity.

Dr. Owe concluded that further studies are needed to explore the risks to the infant associated with increased maternal BMI.

The study and editorial were published Dec. 2 in the BMJ.

The Karolinska Institutet and the Swedish Research Council for Health, Working Life and Welfare funded the study. The Norwegian National Advisory Unit on Women’s Health of Oslo University Hospital funded Dr. Owe's editorial. Dr. Owe and the study authors disclosed no conflicts of interest.

Review Date: 
December 2, 2014
Last Updated:
December 3, 2014