Does delayed perception of the onset of lactation shorten breastfeeding duration?

This longitudinal study evaluated the impact of the timing of maternal perception of the onset of lactation on breastfeeding duration. Breastfeeding mothers who delivered a full-term infant were interviewed daily from day 1 postpartum until the onset of lactation. Women were recontacted to determine the duration of any breastfeeding at 6.7 months postpartum, and if necessary, at 16.2 months postpartum. Cox survival multivariate analyses indicated that among women planning to breastfeed for at least 6 months, those with onset of lactation < 72 hours postpartum were likely to breastfeed longer than their counterparts with a delayed onset of lactation. Median breastfeeding durations were 11.7 months and 3.4 months, respectively (p < 0.00001). Among women who intended to breastfeed for less than 6 months, the timing of the onset of lactation did not influence breastfeeding duration. All analyses controlled for body build, delivery method, employment status, education, parity, and maternal age. These findings suggest that a delayed onset of lactation is likely to be associated with a shorter breastfeeding duration. This relationship, however, was modified by the mother's intended breastfeeding duration.