Social
Unraveling residential segregation and its association with fecundability Sharonda M. Lovett* Sharonda M. Lovett Lauren A. Wise Andrea S. Richardson Erin J. Campbell Yvette C. Cozier Collette N. Ncube Amelia K. Wesselink Mary D. Willis
Introduction: Residential segregation (a proxy for structural racism) is a known determinant of health disparities that has been associated with adverse pregnancy outcomes. However, no study has investigated its association with fecundability, the per-cycle probability of conception.
Methods: We analyzed data from 10,438 U.S. female participants aged 21-45 years enrolled in Pregnancy Study Online (2013-2022), an internet-based preconception cohort study. We ascertained data (including full residential addresses) at baseline, and during follow-up for up to 12 months or until conception. Using baseline residential addresses, we calculated residential segregation based on the Index of Concentration at the Extremes (ICE), which was constructed from American Community Survey 5-year estimates. ICE ranges from -1 (“disadvantaged”) to 1 (“privileged”). We operationalized ICE metrics at the census tract level: economic segregation (ICEincome: ≥$100k vs. <$25k), racial segregation (ICEwhite/black: non-Hispanic White vs. non-Hispanic Black), and racialized economic segregation (ICEincome + white/black: non-Hispanic White ≥$100k vs. non-Hispanic Black <$25k). We used proportional probabilities regression to estimate fecundability ratios (FRs) and 95% confidence intervals (CIs), adjusting for age, calendar year of enrollment, and geographic region of residence.
Results: We observed a monotonic inverse association for increasing quintiles of ICEincome and ICEincome + white/black with fecundability, but less evidence of associations with ICEwhite/black. For instance, relative to ICEincome + white/black quintile 5 (“privileged”), FRs for quintiles 4, 3, 2, and 1 (“disadvantaged”) were 0.92 (95% CI: 0.86-0.99), 0.84 (95% CI: 0.78-0.90), 0.84 (95% CI: 0.78-0.90), and 0.79 (95% CI: 0.73-0.86), respectively.
Conclusion: Living in the most disadvantaged neighborhoods with respect to racialized economic segregation was associated with a moderate decrease in fecundability.