Effect of work status on breast-feeding initiation and duration among U.S. mothers: Results from the Infant Feeding Practices Study II

Data from the Infant Feeding Practices Study II (IFPS II) are used to examine the effect of work status on breastfeeding initiation and duration. IFPS II, conducted in 2005-2007, is a longitudinal study of women from late pregnancy through their infant's first year of life and is a follow-up study to IFPS I, conducted in 1992-1993.

For this study we use data collected prenatally and when the infant was a month old. We also include data on mother's work status when the infant was about 3 months old and breastfeeding duration.

In our subsample of 1584 mother-infant pairs, 86% initiated breastfeeding. This is a 10% increase from IFPS I. However, the average duration of breast-feeding was 22 weeks, about 2 weeks less than before. Controlling for demographic and other characteristics, results show that mothers who expected to work full-time were less likely to initiate breastfeeding than those who did not expect to work (P < 0.001). Initiation rates were equivalent for mothers who expected to work part-time and mothers who did not expect to work (P > 0.05). Additionally, working full-time by month 3 had a strong negative effect on duration relative to not working (P < 0.001), while working between 20 and 34 hours had a less negative effect (P < 0.05) and working 19 hours or less had no effect.

We conclude that working full-time is an important barrier to breastfeeding. Working part-time has no effect on initiation and is less detrimental than working full-time on breastfeeding duration.