Neighborhood disadvantage and menstrual disturbances in a preconception cohort.

OBJECTIVE: Neighborhood disadvantage is associated with adverse reproductive health outcomes, but its association with menstrual disturbances is understudied. Our objective was to estimate the association between neighborhood socioeconomic disadvantage and prevalence of menstrual disturbances (abnormal uterine bleeding and dysmenorrhea). DESIGN: We conducted a cross-sectional analysis of 8,198 participants in Pregnancy Study Online, an internet-based preconception cohort study, enrolled during October 2014 - September 2024. SUBJECTS: Participants were aged 21-39 years, U.S. residents, and not using contraceptives or fertility treatment. EXPOSURE: We linked within-state Area Deprivation Index percentiles to residential addresses by block group and year. MAIN OUTCOME MEASURES: We used self-reported data on typical menstrual cycle characteristics to define abnormal uterine bleeding (irregular cycles, duration of flow ≥7 days, heavy bleeding, or cycle length <24 or >38 days) and dysmenorrhea (severe pain requiring medication use and bed rest). We estimated prevalence ratios and 95% confidence intervals for associations of Area Deprivation Index quartiles with abnormal uterine bleeding and dysmenorrhea using modified Poisson regression models. RESULTS: Neighborhood disadvantage was positively associated with the prevalence of abnormal uterine bleeding (most [Q4] vs. least disadvantaged [Q1] quartile: prevalence ratio = 1.16, 95% confidence interval: 1.05, 1.29) and dysmenorrhea (Q4 prevalence ratio = 1.44, 95% confidence interval: 1.12, 1.85) in models adjusted for age, year, parent's educational attainment, race, and ethnicity. After further adjustment for participant household income, the association between neighborhood disadvantage and abnormal uterine bleeding prevalence was attenuated (Q4 prevalence ratio = 0.99, 95% confidence interval: 0.89, 1.10), whereas neighborhood disadvantage was positively, non-monotonically associated with dysmenorrhea prevalence (Q2 prevalence ratio = 1.40, 95% confidence interval: 1.13, 1.74; Q3 prevalence ratio = 1.42, 95% confidence interval: 1.13, 1.77; Q4 prevalence ratio = 1.21, 95% confidence interval: 0.93, 1.56). CONCLUSION: Living in a more disadvantaged neighborhood was associated with a higher prevalence of menstrual disturbances, particularly dysmenorrhea.