Obesity levels in a national cohort of women 9 months after delivery

OBJECTIVE: The purpose of this study was to examine the relationship between maternal obesity that is calculated 9 months after delivery and sociodemographic variables. STUDY DESIGN: A national cohort of mothers was sampled 9 months after delivery as part of the Growing Up in Ireland Study Infant Cohort. Sociodemographic and clinical details were recorded at the interview by trained fieldworkers who used validated questionnaires. Body mass index was calculated based on weight and height measurements at the postpartum interview. The unadjusted and adjusted odds of obesity were calculated for predictor variables with the use of logistic regression analysis. RESULTS: Of the 10,524 mothers whose cases were studied, the mean age was 31.6 ± 5.5 years, and the mean parity was 1.0 ± 1.1. The mean body mass index after delivery was 25.7 ± 5.4 kg/m(2); 16.8% of the women (n = 1768) were obese. Postpartum maternal obesity levels were associated positively on univariable analyses with smoking, lower household income, African nationality, earlier completion of full-time education, gestational weight gain, lower breast-feeding duration, and increasing parity. On multivariable analysis, maternal obesity was associated with increasing parity in lower income households, but not in higher income households. CONCLUSION: Public health interventions that are aimed at decreasing obesity levels after childbirth should prioritize women who are disadvantaged socioeconomically.