High prepregnant body mass index is associated with poor lactation outcomes among white, rural women independent of psychosocial and demographic correlates.

To determine whether high prepregnant body mass index (BMI) is associated with later onset of lactogenesis II (LGII) and shorter duration of breastfeeding, we questioned 151 women about their demographic and psychosocial characteristics during pregnancy and about the onset of LGII during days 1 to 5 postpartum. Compared to women with earlier (< 72 hours) onset of LGII, those with later onset had a higher BMI (P < .05), a higher proportion of primiparity (P < .01), and a lower infant score on the Mother-Baby Assessment (P < .05). Prepregnant BMI (P < .04) and primiparity (P < .005) were each associated with later onset of LGII, but only primiparity remained significant when both factors were considered simultaneously. These results suggest that, in addition to those who have just delivered their first infant, those with higher prepregnant BMI values also warrant extra support to decrease their risk of early discontinuation of breastfeeding.