Racial and Ethnic Disparities in Cesarean Delivery and Indications Among Nulliparous, Term, Singleton, Vertex Women.

OBJECTIVE: To compare cesarean delivery rates and indications by race/ethnicity among nulliparous women with term, singleton, vertex presentation deliveries. METHODS: This is a retrospective cohort study of nulliparous women delivering term, singleton, vertex neonates at Kaiser Permanente Northern California from 1/1/2016 to 6/30/2017. Women with cesarean for elective, malpresentation, or previa were excluded. Multivariable logistic regression models adjusting for maternal, neonatal, and facility factors were used to assess the likelihood of cesarean by race/ethnicity. Further modeling was performed to examine odds of cesarean for the indications of failure to progress and fetal intolerance by race/ethnicity. RESULTS: The cohort of 16,587 racially/ethnically diverse women meeting inclusion and exclusion criteria consisted of 41.62% White, 27.73% Asian, 22.11% Hispanic, 5.32% Black, and 3.21% multiple race/other women. In adjusted logistic regression models, all race and ethnic categories had higher odds of cesarean deliveries in comparison to White women. Black women had the highest odds of cesarean delivery (adjusted OR [aOR] = 1.73, 95% CI: 1.45-2.06), followed by Asian (aOR = 1.59, 95% CI: 1.45-2.06), multiple race/other (aOR = 1.45, 95% CI: 1.17-1.80), and Hispanic (aOR = 1.43, 95% CI: 1.28-1.59) women. Compared with White women, Asian (aOR = 1.46, 95% CI: 1.22-1.74) and Hispanic (aOR = 1.25, 95% CI: 1.03-1.52) women had higher odds of failure to progress as the indication. Among women with failure to progress, Black (aOR = 0.50, 95% CI: 0.30-0.81), Hispanic (aOR = 0.68, 95% CI: 0.53-0.87), and Asian (aOR = 0.77, 95% CI: 0.61-0.96) women were less likely than White women to reach 10 cm dilation. Compared with White women, Black women were more likely to have cesarean delivery for fetal intolerance (aOR = 1.51, 95% CI: 1.10-2.07). Among women with fetal intolerance of labor, there were no significant differences by race/ethnicity for Apgar score or neonatal intensive care unit admission. CONCLUSIONS: Race/ethnicity was significantly associated with the odds of cesarean and indication. All other race/ethnicity groups had higher odds of cesarean compared with White women. Compared with White women, Black women had greater odds of fetal intolerance as an indication, while Hispanic and Asian women had greater odds of failure to progress. Maternal, neonate, and facility factors for cesarean delivery did not explain the observed disparities in cesarean delivery rates.