Current recommendations for weight gain during pregnancy - developed by the Institute of Medicine (IOM) in 1990 - should be revised, according to an internationally recognized obesity expert and chairman of the department of obstetrics, gynecology and women's health at Saint Louis University.
The editorial by Raul Artal, M.D., who has conducted extensive research on obesity during pregnancy, appears in the March issue of Expert Review of Obstetrics and Gynecology, an international medical journal.
Recommendations by the IOM, which are followed worldwide by obstetricians, encourage obese women to gain at least 15 pounds during pregnancy and specify no upper limit for weight gain. The IOM is a panel of national experts who provide advice on medical and health issues.
Overweight or obese women don't need to gain that much weight and should exercise and watch their calorie consumption during pregnancy, Artal said.
“Pregnancy has become over the years a state of indulgence and confinement,” he wrote. “Pregnancy is an ideal time for behavior modification that includes physical activity and with proper medical supervision it can be safely prescribed.”
The IOM guidelines were not grounded in scientific evidence, Artal said, and focused primarily on preventing low birth-weight deliveries, which generally occur when women who are underweight and of normal weight don't gain enough weight during pregnancy.
He added the guidelines did not take into account the other factors that could restrict the growth of babies. Nor did they consider the impact of excessive weight gain on the health of the fetus and mother, he wrote.
“There is still a prevailing reluctance among health care providers to prescribe lifestyle modification in pregnancy that includes judicious diet and exercise,” Artal said. “The perception is that pregnancy is not an opportune time for such interventions because of potential risk to the fetus.”
If overweight pregnant women control the number of calories they consume and maintain a physically active lifestyle, they can fight problems that commonly come from obesity, such as hypertension and diabetes, he wrote.
Artal recommended that in uncomplicated pregnancies, all women, even those who are obese, should engage in physical activity.
“Previous studies have demonstrated that engaging in exercise activities in pregnancy is safe,” he wrote. “Obese women should not be precluded from engaging in physical activities. Obese pregnant women who engage in physical activities during their pregnancies reduce their risk of developing gestational diabetes by 50 percent.”
In addition, obese women should limit the amount of weight they gain during pregnancy by eating only enough to provide adequate calories and nourishment for their growing babies.
Artal blamed the obesity epidemic in part on excessive weight gain during pregnancy.
“We can certainly speculate that for overweight and obese pregnant women who gained at least 15 pounds during their pregnancies (and evidence suggests that they gain more), pregnancy has become a major contributing factor to the epidemic of obesity, since the general tendency is to retain the weight post-partum.”
He urged overweight women who are pregnant to exercise and change their eating habits, which would have a trickle-down effect on the health of the entire family as everyone is likely to eat healthier.
“Pregnancy is the time when women are motivated to make changes to improve their lifestyle. It is an optimal time for health care providers to offer their support through community resources to decrease maternal obesity thus impacting the lives of future generations,” Artal wrote.