BACKGROUND:

For many women, pregnancy begets long-term weight gain. Modifiable behaviors that contribute to postpartum weight retention have not been well studied.

METHODS:

Prospective cohort study of 902 women enrolled in Project Viva, examining associations of postpartum television viewing, walking, and trans fat intake with weight retention equal to or greater than 5 kg at 12 months postpartum. Data were collected in 1999-2003 and analyzed in 2005-2006.

RESULTS:

At 6 months postpartum, women reported a mean (SD) of 1.7 (1.3) hours of television viewing, 0.7 (0.7) hours of walking, and 1.1% (0.5) of energy intake from trans fat per day. At 1 year, participants retained a mean of 0.6 kg (range: -17.3 to 25.5), and 12% retained at least 5 kg. In multivariate logistic regression models, adjusting for maternal sociodemographics, parity, prepregnancy body mass index, gestational weight gain, breastfeeding, and smoking, the odds ratio of retaining at least 5 kg was 1.24 (95% confidence interval [CI]: 1.06-1.46) per daily hour of television viewing, 0.66 (95% CI: 0.46-0.94) per daily hour of walking, and 1.33 (95% CI: 1.09-1.62) per 0.5% increment in daily energy intake from trans fat. Women who watched less than 2 hours of television, walked at least 30 minutes, and consumed trans fat below the median had an odds ratio of 0.23 (95% CI: 0.08-0.66) of retaining at least 5 kg.

CONCLUSIONS:

Postpartum television viewing, walking, and trans fat intake were associated with weight retention. Interventions to modify these behaviors may help reduce excess postpartum weight gain and prevent obesity among women.