Weight and behavioral and psychosocial factors among ethnically diverse, low-income women after childbirth: I. Methods and context

Objective: In this paper, we present the background, hypotheses, methods, and descriptive findings from the Austin New Mothers Study, a longitudinal series measuring weight and contextual variables across the first postpartum year. Among the distinguishing features of this study are its tri-ethnic sample of low-income women and its serial measurement of the behavioral and psychosocial context of postpartum weight changes post-delivery and at 6 weeks, and 3, 6, and 12 months postpartum. Method: A prospective longitudinal design was used to assess body mass index (BMI), energy intake, fat intake, physical activity, health-related lifestyle, depressive symptoms, body image, and weight-related distress at each observation. Sample: The analytic sample consisted of 382 White, African American, and Hispanic women. Findings: For BMI, effects for ethnicity (p <.001), time (p < .001), and their interaction (p = .005) were significant. All ethnic groups had significant declines in BMI from delivery to 6 weeks postpartum. Thereafter, BMIs of White women declined during the second 6 months, whereas those of Hispanic and African American women either displayed small gains or plateaus between adjacent observations. Time-related effects were significant for behavioral and psychosocial variables except for body image and weight-related distress, whereas effects for ethnicity were significant on fat intake, depressive symptoms, and body image. Despite declines in depressive symptoms, women remained at risk of depression across the first postpartum year. Conclusions: Low-income ethnic minority women have a higher vulnerability to postpartum weight gains or plateaus, High depressive symptoms occurred in all ethnic groups examined.