Role of Marital Status in the Association between Prepregnancy Body Mass Index and Breastfeeding Duration

Abstract

BackgroundIn the United States, breastfeeding rates fail to meet national guidelines. Given the rising prevalence of obesity and births to unmarried women, this study explores if the association between prepregnancy body mass index (BMI) and breastfeeding duration differs by marital status. MethodsData from the 2009–2011 Pregnancy Assessment Monitoring System were analyzed. The sample included women who had live singleton births in the United States and who reported information to calculate BMI and breastfeeding duration (n = 93,106). Breastfeeding duration was categorized as never breastfed, breastfed for 8 weeks or less, and breastfed for more than 8 weeks. BMI was categorized as underweight (<18.5 kg/m2), normal weight (18.5–24.9 kg/m2), overweight (25.0–29.9 (kg/m2), or obese (30.0 + kg/m2). Marital status was categorized as married or not married. There was a significant interaction between marital status and prepregnancy BMI (p = .028). Data were stratified by marital status and multinomial logistic regression was conducted adjusting for confounding factors. ResultsApproximately one-half of women were of normal weight before pregnancy (50.4%); 24.1% were overweight, 21.2% were obese, and 4.3% were underweight. Among married women, the odds of never breastfeeding and breastfeeding for 8 weeks or less was greater among overweight (adjusted odds ratio [AOR], 1.23 [95% confidence interval {CI}, 1.10–1.38]; AOR, 1.36 [95% CI, 1.24–1.49]) and obese women (AOR, 1.72 [95% CI, 1.53–1.93]; AOR, 1.95 [95% CI, 1.77–2.15]) compared with normal weight women who breastfed for more than 8 weeks. In contrast, among unmarried women, no association was observed among overweight women and the association was attenuated among obese women (AOR, 1.38 [95% CI, 1.21–1.58]; AOR, 1.43 [95% CI, 1.27–1.62]). ConclusionProviders and public health practitioners should be aware of the influence of marital status in the association between prepregnancy BMI and breastfeeding duration. The role of obesity and marital status should be considered in designing breastfeeding promotion interventions.