A group prenatal care intervention reduces gestational weight gain and gestational diabetes in American Samoan women.

Objective: The objective of this study was to determine the preliminary effectiveness of an intervention to mitigate adverse pregnancy outcomes associated with pre-pregnancy obesity in American Samoa.

Methods: We enrolled n = 80 low-risk pregnant women at <14 weeks' gestation. A complete case analysis was conducted with randomized group assignment (group prenatal care-delivered intervention vs. one-on-one usual care) as the independent variable. Primary outcomes were gestational weight gain and postpartum weight change. Secondary outcomes included gestational diabetes screening and exclusive breastfeeding at 6 weeks post partum. Other outcomes reported include gestational diabetes incidence, preterm birth, mode of birth, infant birth weight, and macrosomia.

Results: Gestational weight gain was lower among group versus usual care participants (mean [SD], 9.46 [7.24] kg vs. 14.40 [8.23] kg; p = 0.10); postpartum weight change did not differ between groups. Although the proportion of women who received adequate gestational diabetes screening (78.4% group; 65.6% usual care) was similar, there were clinically important between-group differences in exclusive breastfeeding (44.4% group; 25% usual care), incidence of gestational diabetes (27.3% group; 40.0% usual care), and macrosomia (8.3% group; 29.0% usual care).

Conclusions: It may be possible to address multiple risk factors related to intergenerational transmission of obesity in this high-risk setting using a group care-delivered intervention.