About 48 % of US women gain more weight during pregnancy than recommended by the Institute of Medicine (IOM). Excessive gestational weight gain is a major risk factor for obesity in both women and offspring over their lifetimes, and should be avoided. This study was designed to test the feasibility and initial efficacy of a prenatal behavioral intervention in a sample of low-income, predominantly Latina women. The intervention was delivered in groups of 8-10 women in a community recreation center, and structured to reduce the proportion of women who gained weight in excess of IOM guidelines. Recruitment targets were met in 3 months: 135 pregnant women (>10 and <28 weeks) were randomly assigned to receive a 12-week intervention (n = 68) or usual care (n = 67). Retention rate was 81 %. On average, women attended 4 of 12 group sessions, and each session had 4 of the 8-10 assigned participants in attendance. Initial efficacy analyses were based on 87 women. Compared to usual care, fewer normal-weight women in the intervention exceeded IOM recommendations (47.1 % usual care vs. 6.7 % intervention; absolute difference 40.4 %; p = .036). Recommendations for recruitment, retention, and delivery are discussed. A community-based cognitive-behavioral lifestyle intervention during pregnancy was feasible in a hard-to-reach, high-risk population of low-income Latina women, and showed efficacy in preventing excessive gestational weight gain. Due to frequently changing work schedules, strategies are needed to either increase attendance at group sessions (e.g., within a group prenatal care format) or to build core skills necessary for behavior change through other modalities.
Trial registration: ClinicalTrials.gov NCT01279109.