Increased BMI associated with decreased breastfeeding initiation in Million Veteran Program participants

Abstract

AbstractBackgroundBreastfeeding has been associated with maternal and infant health benefits but has been inversely associated with body mass index (BMI) prepartum. Breastfeeding and BMI are both linked to socioeconomic factors.MethodsData from parous female participants with available breastfeeding information from the Million Veteran Program cohort was included. BMI at enrollment and earliest BMI available were extracted, and polygenic scores (PGS) for BMI were calculated. We modeled breastfeeding for one month or more as a function of BMI at enrollment; earliest BMI where available pre-pregnancy; and PGS for BMI. We conducted Mendelian randomization for breastfeeding initiation using PGS as an instrumental variable.ResultsA higher BMI predicted a lower likelihood of breastfeeding for one month or more in all analyses. A +5 kg/m2BMI pre-pregnancy was associated with a 24% reduced odds of breastfeeding, and a +5 kg/m2genetically predicted BMI was associated with a 17% reduced odds of breastfeeding.ConclusionsBMI predicts a lower likelihood of breastfeeding for one month or longer. Given the high success of breastfeeding initiation regardless of BMI in supportive environments as well as potential health benefits, patients with elevated BMI may benefit from additional postpartum breastfeeding support.