The Association between Maternal Race and Ethnicity and Risk Factors for Primary Cesarean Delivery in Nulliparous Women.

Objective  To understand whether maternal, perinatal, and systems-level factors can be identified to explain racial/ethnic disparities in cesarean delivery rates. Study Design  This retrospective cohort study included nulliparous women with singleton gestations who delivered at a tertiary care center from 2015 to 2017. Maternal, perinatal, and systems-level factors were compared by race/ethnicity. Multilevel multivariable logistic regression was used to identify whether race/ethnicity was independently associated with cesarean. Effect modification was evaluated using interaction terms. Bivariable analyses and multinomial logistic regression were used to determine differences in indication for cesarean. Results  Of 9,865 eligible women, 2,126 (21.5%) delivered via cesarean. The frequency of cesarean was lowest in non-Hispanic white women (19.2%) and highest in non-Hispanic black women (28.2%; p  < 0.001). Accounting for factors associated with cesarean delivery did not lessen the odds of cesarean associated with non-Hispanic black race (aOR: 1.58, 95% CI: 1.31–1.91). Compared with non-Hispanic white women, non-Hispanic black women were more likely to undergo cesarean for nonreassuring fetal status (aOR: 2.73, 95% CI: 2.06–3.61). Conclusion  Examined maternal, perinatal, and systems-level risk factors for cesarean delivery did not explain the racial/ethnic disparities observed in cesarean delivery rates. Increased cesarean delivery for nonreassuring fetal status contributed substantially to this disparity. [ABSTRACT FROM AUTHOR]