The sleeper effect of perceived insufficient milk supply in US mothers

Objective: To test whether perception of insufficient milk (PIM) supply in the breast-feeding relationship of one child predicts how long mothers breast-feed subsequent children, and whether this association differs for first-time mothers v. mothers with previous children. Design: Secondary analysis of Infant Feeding Practices Study II (ordinary least squares regression) and Year 6 follow-up. Setting: Mailed, self-report survey of US mother-infant dyads, 2005-2012. Participants: Women pregnant with a singleton were recruited from a consumer opinion panel. Exclusion criteria included: mother age <18; infant born <5 lbs, born before 35 weeks or with extended NICU stay, and mother or infant diagnosed with condition that impacts feeding. A subsample with PIM data (n 1460) was analysed. Results: We found that women who weaned because of PIM with the index child stopped breast-feeding 5 center dot 7 weeks earlier than those who weaned due to other reasons (4 center dot 9 weeks earlier for multiparas, P < 0 center dot 001; 7 center dot 1 weeks earlier for primiparas, P < 0 center dot 001). Using Year 6 follow-up data (n 350), we found subsequent child 1 weaned 9 center dot 2 weeks earlier if the mother experiences PIM as a multipara (P = 0 center dot 020) and 10 center dot 6 weeks earlier if the mother experiences PIM as a primipara (P = 0 center dot 019). For subsequent child 2 (n 78), the magnitude of association was even larger, although insignificant due to low power. Conclusions: These findings indicate that PIM may carry forward in the reproductive life course, especially for first-time mothers. Perceptions of breast milk insufficiency and contributors to actual inadequate milk supply with the first child should be targeted, rather than intervening later in the reproductive life course.

Automated summary

The study found that mothers who perceived insufficient milk supply and weaned their index child earlier than those who stopped breastfeeding for other reasons, especially impacting first-time mothers. Subsequent research also showed that for multiparous mothers, perceiving insufficient milk supply led to weaning the first child earlier by 9.2 weeks, while for primiparous mothers, it was 10.6 weeks earlier.