Abstract A014: Racial and socioeconomic disparities in breast feeding and the impact of pregnancy-related medical conditions among a population-based sample of non-Hispanic Black and White women

Abstract Background: Breastfeeding has been associated with a reduced risk of breast cancer (BC), particularly with Triple Negative BC (TNBC). The risk of TNBC is higher among premenopausal women, Black/African American (AA) women, and poorer women. Notably there are significant disparities in breastfeeding, where non-Hispanic Black (NHB) women and poorer women are less likely to breastfeed in the United States. Studies have identified historical racial trauma, unsupportive work and hospital policies, breast milk formula advertising, and knowledge and beliefs about breast feeding as factors that contribute to breast feeding practices. However, there is a paucity of research on pregnancy related medical conditions (PMCs) that potentially impact initiation and duration of breastfeeding. The purpose of this study is to evaluate racial and socioeconomic differences in breastfeeding, and if PMCs impact breastfeeding practices in a population-based sample of non-Hispanic Black and White women. Method: Data are from the Young Women’s History and Health Study (YWHHS), a population- based case-control study of invasive BC among non-Hispanic Black (NHB) and non-Hispanic White (NHW) women aged 20-49 years residing in Metropolitan Detroit and Los Angeles County, 2010-2015. The analytic sample here includes the first pregnancy of control participants with singleton live births (n=675). Area-based control participants were sampled from the 2010 Census. Interviews assessed complete reproductive histories, including breastfeeding history (never, 6 months, and ≥6 months), PMCs experienced during pregnancy, self-reported race, and household financial struggles before age 13 years (to approximate childhood socioeconomic position (chSEP)). PMCs examined included: 1) premature birth, 2) diabetes or pre-diabetes related PMCs, 3) blood pressure-related PMCs, and 4) BMI ≥ 25 kg/m2 at age 18 years. Weighted percentages were evaluated with a chi-square test and considered significant at p 0.05. Analyses were further stratified by race/ethnicity and chSEP. Result: NHB women were 2.4 times significantly more likely to never breastfeed than NHW women (W% =52.0 (NHB) and 21.3 (NHW), p=0.0001). Similarly, women with lower compared to higher chSEP were 1.5 times significantly more likely to never breastfeed (W% = 42.7 (lower chSEP) and 28.5 (higher chSEP), p=0.003). Those with BMI ≥ 25 kg/m2 at age 18 years (p0.001) alone, and with one or more PMCs (p=0.01) were also less likely to breastfeed. When stratified by race/ethnicity the pattern of breastfeeding did not differ significantly by any PMC within NHB and NHW women. When stratified by chSEP, however, BMI ≥ 25 kg/m2 at age 18 years (p = 0.004) and having one or more PMCs (p=0.03) were significantly associated with never breastfeeding among those with higher chSEP. Conclusion: NHB women and women with lower chSEP were substantially less likely to breastfeed. Additionally, BMI ≥ 25 kg/m2 at age 18 and PMCs were associated with lower frequency of breastfeeding overall and among those with higher chSEP. Citation Format: Meheret B. Gebreegziabher, Lydia R. Post, Chris C. Cho, Zhenzhen Zhang, Kelly A. Hirko, Dorothy R. Pathak, Ann S. Hamilton, Ann G. Schwartz, Ellen M. Velie. Racial and socioeconomic disparities in breast feeding and the impact of pregnancy-related medical conditions among a population-based sample of non-Hispanic Black and White women abstract. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A014.