UCLA

Breastfeeding is one of the most effective ‘interventions’ for reducing infant mortality. Despite ongoing efforts to promote breastfeeding, current breastfeeding rates in the U.S. are still low, and socioeconomic and racial/ethnic disparities in breastfeeding practices have persisted. Improving breastfeeding practices among socially disadvantaged groups remains challenging. The goal of this dissertation is to improve breastfeeding rates and reduce racial/ethnic disparities in breastfeeding practices in the United States. Specifically, this dissertation aims to: (1) assess the influences of breastfeeding support from family, hospitals and workplaces on breastfeeding duration; (2) determine the extent to which racial/ethnic disparities in breastfeeding duration could be explained by breastfeeding support; and (3) estimate the population impact of multifaceted breastfeeding promotion interventions. Using data on approximately 4,000 mothers enrolled in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC), from the triennial Los Angeles County WIC Survey (2014, 2017), this dissertation found that breastfeeding support from family, hospitals and workplaces was significantly associated with longer breastfeeding duration, and that Black mothers and English-speaking Latina mothers have significantly lower breastfeeding rates than White mothers, with the difference widening over increasing duration. Results from causal mediation analysis (specifically, g-computation) showed that lack of access to breastfeeding support from family, hospitals and workplaces accounted for approximately two-thirds of the difference in breastfeeding duration between White and Black mothers, and one-third of the difference between White and English-speaking Latina mothers. This dissertation also illustrated the use of agent-based modeling (ABM) for estimating the population impact of five selected breastfeeding promotion interventions (improving knowledge, implementing Baby-Friendly Hospital Initiative practices, providing breastfeeding counseling, strengthening family support, and fostering supportive workplace environments) implemented singly or in combination with each other. The ABM demonstrated that while improving knowledge and increasing the availability of Baby-Friendly Hospital Initiative practices improve breastfeeding initiation rates, breastfeeding counseling, family support and a supportive workplace environment are more effective in improving breastfeeding duration. Increasing the coverage of multiple interventions simultaneously had a synergistic effect on breastfeeding duration, with their effects being greater than the additive effects of increasing the coverage of these interventions singly.