Structured Programs Needed
"The study demonstrates that women who complete a structured diet and physical activity intervention during the early postpartum period successfully lose weight," says Mary L. O'Toole, PhD, principal investigator and professor of obstetrics, gynecology and women's health at Saint Louis University School of Medicine. "Those given general advice about diet and exercise do not."
The study is important in addressing the obesity epidemic because it focused on women who were overweight when they became pregnant. (Overweight women have a body mass index (BMI) of between 25 and 30; obese women have a BMI of more than 30.)
"Obesity has become such a severe problem that we need to identify times when people are at risk of becoming obese and prevent it from happening," O'Toole says. "The postpartum period is a time we know women tend to retain the weight they gained during pregnancy and start in a downward spiral."
Women who attended 12 weekly diet and activity education sessions lost an average of 16 pounds at the end of the year's study.
By contrast, women who received a single hour-long educational session on diet and exercise lost an average of slightly less than three pounds.
"At this critical time, people need continual reinforcement," O'Toole says. "If you do that one time a week for 12 weeks, they will successfully lose weight. You can't just tell women one time that they need to consume less than 1,600 calories and walk 30 minutes a day."
The study attracted 40 moms whose babies were between 6 weeks and 6 months old, had gained more than 33 pounds during pregnancy, and were more than 11 pounds heavier than that when they became pregnant. Their weight loss progress was followed for a year.
About half the moms were placed in a group that met for 12 weekly nutrition and physical activity strategy sessions. They received individualized prescriptions for diet and exercise and kept track of their activities and what they ate. After a year, they lost an average of 16 pounds.
Women in the other group met individually with a dietitian and exercise physiologist who instructed them on healthy diet and exercise practices during a single 60-minute session. They lost, on average, slightly less than three pounds.
O'Toole says 17 of the women -- more than 40 percent - dropped out of the study before year's end.
"Postpartum women have difficulty in maintaining active participation in a diet and exercise program," she says. "We speculate that the added responsibilities and time-consuming nature of caring for an infant and the necessity of returning to work may have been factors."
The study shows how difficult it is for even highly-motivated women with young children to commit to a diet and exercise program. "Future research should be directed at identifying barriers that may be unique to the postpartum period as well as means to overcome these barriers," O'Toole says.