Contextualizing online human milk sharing: structural factors and lactation disparity among middle income women in the U.S.

Women in the U.S. face significant structural constraints in attempting to breastfeed as recommended in the first six months of their child's life. Internet-facilitated human milk sharing is an emergent response to breastfeeding challenges. Little is known about the demographic characteristics of milk sharing donors and recipients and the ways structural factors circumscribe the biocultural context of lactation in milk sharing practices. Data regarding demographic characteristics, reproductive history, lactation history, and levels of social support and health care provider support for breastfeeding were collected via an online survey September 2013-March 2014. Statistical tests were executed to ascertain whether significant differences exist between donors and recipients. A total of 867 respondents (661 donors, 206 recipients) met the eligibility criteria for the study. Respondents were U.S. residents and primarily White, middle-class, well educated, and employed women. Both donors and recipients reported higher than the national average for household income, maternal educational attainment, breastfeeding exclusivity 0-6 months, and breastfeeding duration. Differences in lactation sufficiency and breastfeeding outcomes between donors and recipients were associated with both structural and biocultural factors. Donors reported significantly higher income, education, and support for breastfeeding from spouse/partner, other family, employers, and pediatricians. Donors also reported significantly higher rates of full term birth for child of most recent lactation. This study provides a foundation for understanding how milk sharing reflects a broader political economy of breastfeeding in the U.S.