Moms-to-be considered obese (those who have a body mass index greater than 30) are typically recommended to gain anywhere from 11 to 20 pounds total during pregnancy as a way to reduce risk for gestational diabetes and other weight-related prenatal complications. But could a weight gain goal of zero be even better?
A December 2009 New York Times article highlights the work of the “Healthy Moms” study, a weight maintenance program for obese pregnant women run by researchers at California’s Kaiser Permanente Center for Health Research. Women enrolled in the program meet privately with a dietitian and participate in weekly support groups. They also follow a closely monitored low-fat diet that emphasizes fruits, vegetables, whole grains, lean meat, and low-fat dairy products—a total calorie count of about 2,000 calories a day and enough, say researchers, to provide ample nutrition for both mom and baby.
“The goal of the study is to keep obese pregnant women from gaining weight. We believe they can safely maintain their pre-pregnancy weight and deliver healthier babies,” said Kim Vesco, MD, MPH, a practicing OB/GYN and researcher at the Kaiser Permanente Center for Health Research. If they do gain weight, researchers want it limited to 3 percent of their baseline weight. The program is expected to run for at least the next four years.
Some health experts disagree with taking such a strict approach to prenatal weight gain. Talking to the New York Times, Dr. Naomi E. Stotland, an assistant professor of obstetrics, gynecology, and reproductive sciences at the University of California, San Francisco, worries that obese women who do not gain weight will burn fat for energy, producing acidic compounds called ketones, which could be harmful to the fetus. According to Stotland, studies in diabetic women and in animals have found that babies born to women who had more ketones in their blood had lower I.Q. scores than other babies.
Other experts urge all women to stick with the conventional wisdom that eating 150 to 300 extra calories a day will provide the extra nourishment needed by a growing baby. With so much conflicting news, the best way to find out the right prenatal weight gain goal for you? Ask your doctor or midwife.