Ethnic disparities in postpartum hemorrhage after cesarean delivery: a retrospective case-control study

To explore the relationship of ethnicity and postpartum hemorrhage (PPH) for women who underwent cesarean delivery (CD) and examine the risk factors for PPH in distinct ethnic groups in China.

We conducted case-control studies with the maternity data from the 11,778 CD cases, in Xinjiang Uygur Autonomous Region. Initially, multivariable logistic regression was used to estimate the disparity of race-ethnicity on the risk of PPH in ethnic Han, Uygur, Hui and Kazakh. Then, we performed case-control studies within two major ethnic groups, identifying the specific risk factors for PPH.

Ethnic Uygur were associated with a statistically significant increased odds [adjusted odds ratios (aOR) 2.05; 95% confidence interval (CI) 1.26-3.33] of PPH compared with ethnic Han. For subgroup analyses, in Uygur subgroup, general anesthesia (aOR 7.78; 95% CI 2.31-26.20); placenta previa (aOR 11.18; 95% CI 3.09-40.45); prenatal anemia (aOR 4.84; 95% CI 2.44-9.60); emergency surgery (aOR 4.22; 95% CI 1.95-9.13) were independently associated with PPH. In Han subgroup, general anesthesia (aOR 5.70; 95% CI 1.89-17.26); placenta previa (aOR 20.08; 95% CI 6.35-63.46); multiple pregnancy (aOR 7.21; 95% CI 1.61-32.37); body mass index (aOR 1.19; 95% CI 1.07-1.31) were the risk factors to PPH.

Uygur have more tendency to PPH compared to Han, and risk factors for PPH in Uygur and Han groups may differ. Knowing these differences may be meaningful when planning interventions and resources for high-risk patients undergoing cesarean delivery, and we need more research aimed at risk factors for PPH.