SAN ANTONIO – Education about appropriate weight gain, healthy eating, and exercise during pregnancy improves dietary restraint and self-weighing, and prevents postpartum weight retention, according to 12-month findings from the randomized, controlled Fit for Delivery study.
Benefits accrued even after the "pretty practical, low-intensity intervention" ended, suggesting that "pregnancy may be a teachable moment for promoting continued behavioral changes," Suzanne Phelan, Ph.D., of California Polytechnic State University, San Luis Obispo, reported at the annual meeting of the Obesity Society.
Among 201 normal-weight study participants, 40% of those randomized to receive standard care plus a lifestyle modification intervention exceeded 1990 Institute of Medicine recommendations for weight gain during pregnancy, compared with 52% of those randomized to receive standard care as part of a control group.
No such difference was seen among 200 overweight or obese participants in the intervention and control groups (67% and 61%). Regardless of weight status at study entry, 31% of 201 women in the intervention group returned to their prepregnancy weight by 6 months post partum, compared with 19% of 200 women in the control group.
The 6-month results of the Fit for Delivery study were published last year in the American Journal of Clinical Nutrition (2011;93:772-9). Dr. Phelan’s presentation included findings at 12 months’ follow-up.
At 12 months post partum, 45% of normal-weight and overweight/obese participants in the intervention group and 35% in the control group reached their prepregnancy weight. The women in the intervention group may have been more successful because they exhibited significantly greater dietary restraint and were significantly more likely to monitor their weight throughout the study period. For example, the intervention group reduced calories consumed from soft drinks during pregnancy and until 6 months’ follow-up.
More sophisticated analyses to explore the complex relationships between potential mediators of treatment effects are underway, she added.
Fit for Delivery study participants were pregnant women recruited from six obstetrics practices between 2006 and 2008. At study entry, their mean age was 29 years and mean gestation was 13.5 weeks. Two-thirds were non-Hispanic white women and 77% were primiparous. Half were normal weight and half were overweight or obese.
Those in the intervention group had one 30-minute face-to-face visit, three phone calls throughout pregnancy (with more for those gaining more or less than the recommended amount of weight), and mail delivery of "challenge cards" highlighting key behavioral targets such as healthy eating and physical activity. The intervention group also received a scale, pedometer, and nutritional resources such as calorie-counting booklets.
A motivational approach to the intervention, which ended at delivery, aimed to teach participants to consider the impact of their behavior on the health of their growing baby, Dr. Phelan noted.
Participants in the control group had one face-to-face visit with a dietitian, and received general educational brochures and newsletters about pregnancy-related topics.
The final analysis excluded 6 women who experienced a miscarriage, 32 who developed gestational diabetes, 5 who became pregnant within 6 months of delivery, and an additional 36 who became pregnant within 12 months of delivery.
Excessive gestational weight gain is a major determinant of high postpartum weight retention as well as long-term obesity and several adverse maternal and offspring outcomes, Dr. Phelan said. About half of normal-weight women and 65% of overweight or obese women gain more weight than recommended during pregnancy.
This type of program could be useful in the clinical setting, she added, noting that additional research to evaluate the effects of higher-intensity programs is needed.
The Fit for Delivery study was supported by the National Institutes of Health. Dr. Phelan and her colleagues reported having no relevant financial disclosures.