Lifestyle interventions cut gestational weight gain

Lifestyle intervention can help reduce risk of gestational weight gain in expectant mothers, researchers reported. The two trials were part of the Lifestyle Interventions for Expectant Moms (LIFEMoms) consortium of seven clinical trials. In one study, a lifestyle program, including nutrition and physical activity intervention, reduced the amount of gestational weight gain versus usual obstetrical care (-3.95 lbs between-group difference, P=0.003).

Infants of mothers who underwent this lifestyle intervention had greater weight (difference of +131 g, P=0.03) and fat-free mass (+98 g, P=0.03), according to Dympna Gallagher, EdD, of Columbia University in New York, and colleagues, in Obesity.

In another trial, a similar intervention involving a home-based lifestyle program led to significant reduction in the amount of gestational weight gain in disadvantaged overweight or obese women, reported Alison G. Cahill, MD, of Washington University in St. Louis in Missouri, and colleagues, also in Obesity.

"Both trials partnered with or used an existing evidence-based program or curriculum as the basis of the lifestyle intervention that was tested, increasing the likelihood of the translation of their interventions into practice," commented Christine M. Olson of Cornell University in Ithaca, New York, and Rüdiger von Kries, of Ludwig-Maximilians-Universität München in Munich, Germany, in an accompanying commentary.

Gallagher's group assessed 210 pregnant women who had overweight or obesity. They were randomized to either receive lifestyle intervention or usual obstetrical care before the second trimester of pregnancy.

The most notable benefit of the intervention was seen in women with obesity (difference -5.91 lbs, P=0.007), while the between-group difference in gestational weight gain in overweight women did not reach significance. However, women with overweight and obesity receiving this intervention were far less likely to gain more than the ranges for weight gain recommended by the National Academy of Medicine (formerly IOM).

Cahill's group reported similarly positive outcomes with a home-based lifestyle intervention administered to socioeconomically disadvantaged African-American women with either overweight or obesity. The intervention was delivered by the Parents as Teachers (PAT) group, who visited the homes of the participants 10 times throughout pregnancy.

Usual PAT care, which served as the control for the trial, was concentrated on "development-centered parenting support and education" as well as teaching parent-child interaction. The modified, lifestyle PAT program included both the standard care, in addition to behavioral modifications centered around healthy eating and physical activity to achieve weight goals.

Not only was total gestational weight gain reduced in modified PAT program, but the expected increase insulin AUC and systolic blood pressure with advancing gestational was lower in the intervention group.

Olson and von Kries called these benefits "modest" in their impact on weight gain during pregnancy.

"The following two results from these trials contribute to the lack of clarity: no intervention effect on infants' percent body fat and body fat mass and the finding of no significant association between infants' lean body mass and maternal GWG [gestational weight gain]" they critiqued, adding that it's "challenging to match these findings with pathophysiological pathways for a causal relationship between excessive GWG and childhood risk for later overweight."

Follow-up data on the offspring from these trials might help to elucidate any causal role of gestational weight gain and future overweight or obesity risk in these offspring, they suggested.

Cahill, A. G., Haire-Joshu, D., Cade, W. T., Stein, R. I., Woolfolk, C. L., Moley, K., Mathur, A., Schechtman, K. and Klein, S. (2018), Weight Control Program and Gestational Weight Gain in Disadvantaged Women with Overweight or Obesity: A Randomized Clinical Trial. Obesity, 26: 485–491

Gallagher, D., Rosenn, B., Toro-Ramos, T., Paley, C., Gidwani, S., Horowitz, M., Crane, J., Lin, S., Thornton, J. C. and Pi-Sunyer, X. (2018), Greater Neonatal Fat-Free Mass and Similar Fat Mass Following a Randomized Trial to Control Excess Gestational Weight Gain. Obesity, 26: 578–587