Weight and behavioral and psychosocial factors among ethnically diverse, low-income women after childbirth: II. Trends and correlates

Objective: This paper presents a longitudinal analysis of behavioral and psychosocial correlates of weight trends during the first postpartum year. Data are derived from the Austin New Mothers Study (ANMS), a longitudinal study of a low-income, tri-ethnic sample of postpartum women that incorporated serial assessment of weight and behavioral and psychosocial variables. Method: Postpartum body mass index (BMI) was measured prospectively (post-delivery, 6 weeks, and 3, 6, and 12 months postpartum). The analytic sample consisted of 382 White, African American, and Hispanic women receiving maternity care funded by Medicaid who had at least three measured postpartum weights. Behavioral and psychosocial variables included energy intakes, fat intakes, physical activity, health-related lifestyle, smoking, breastfeeding, contraception, depressive symptoms, emotional eating, body image, and weight-related distress. Results: Using hierarchical linear modeling to incorporate baseline only and time-varying effects, significant associations with postpartum BMI were found for the following variables: ethnicity (p = .001), time of weight measurement (p < .001), the interaction of ethnicity and time (p = .005), prepregnant BMI (p < .001), gestational weight gain (p < .001), weight-related distress (p < .001), and energy intakes (p = .005). After adjusting for covariates, ethnic groups displayed differing trends in postpartum BMI resulting in White women having significantly lower BMIs at 12 months postpartum compared to ethnic minority women (p's < .01). Conclusion: Behavioral and psychosocial variables contribute to a fuller understanding of BMI status of low-income women during the first postpartum year.