Maternal Weight Over Successive Pregnancies and Breastfeeding Initiation, Duration and Exclusivity

Abstract

Maternal overweight and obesity have been shown to adversely affect breastfeeding success. This study aims to examine the relationship between maternal weight status over the course of 2 successive pregnancies and breastfeeding initiation, duration and exclusivity among a low income diverse sample. Mothers enrolled in Massachusetts WIC (2001–2009) with two consecutive (linked) pregnancies were included. Only those with singleton, full term, live, adequate‐birth‐weight infants and with complete breastfeeding (2nd birth) and covariate (n=10,157)) data were included. Maternal weight status was examined using the following variables: change in weight classification between pregnancies 1–2 using pre‐pregnancy weight (none, decrease, increase), 2nd pre‐pregnancy weight status (underweight, normal weight, overweight, obese) and gestational weight gain (IOM 2009 recommendations) during the second pregnancy. Breastfeeding outcomes were initiation, duration and whether or not infants were exclusively breastfed for at least 4 weeks. Covariates included the following: race/Hispanic ethnicity, maternal age and education, first pregnancy breastfeeding initiation/duration, timing of WIC entry, smoking post‐partum. Multivariate Logistic Regression was used to examine associations with breastfeeding initiation, and exclusivity, while General Linear Model Regression was used to examine breastfeeding duration. The sample was diverse (52.4% nonwhite) with a mean age of 24.5 years (SD=5.0). At the start of their second pregnancy, 50.7% of women were overweight or obese; 28.1% of women shifted to a higher weight status classification between their 1st and 2nd pregnancies, while 5.0% shifted to a lower weight class. After the second pregnancy, 58.6% initiated breastfeeding; mean breastfeeding duration was 9.0 weeks among initiators (SD=15.9). Weight gain during pregnancy was not associated with any of the breastfeeding outcomes, however, 2nd pregnancy's pre‐pregnancy weight status, and change in weight class category were. Women who were obese prior to their second pregnancy were 24% less likely to initiate breastfeeding (AOR(95%CI))=0.76 (0.67–0.87) than those normal weight. Those whose weight class declined between pregnancies were 30% more likely to initiate breastfeeding (AOR=1.30 95% CI=1.03–1.64) than those whose weight status stayed the same. Mothers who were obese, breastfed for a shorter duration (p<.05) than those who were overweight (12.2 vs. 13.9 weeks), or normal weight (13.2 weeks). Obese mothers were less likely to exclusively breastfeed for at least four weeks compared to normal weight mothers (AOR=0.57, p < .05). No associations were found with other weight status categories. Both weight status prior to pregnancy and changes over subsequent pregnancies appear to be associated with breastfeeding success in a low income diverse population.Support or Funding InformationNo support.