Effect of race/ethnicity on risk of complete and partial molar pregnancy after adjustment for age

Objective. To quantify the effect of race/ethnicity on risk of complete and partial molar pregnancy. Methods. We conducted a cross-sectional study including women who were followed for complete or partial mole and those who had a live singleton birth in a teaching hospital in the northeastern United States between 2000 and 2013. We calculated race/ethnicity-specific risk of complete and partial mole per 10,000 live births, and used logistic regression to estimate crude and age-adjusted relative risks (RR) of complete and partial mole. Results. We identified 140 cases of complete mole, 115 cases of partial mole, and 105,942 live births. The risk of complete mole was 13 cases per 10,000 live births (95% confidence interval [CI] 11-16) and that of partial mole was 11 cases per 10,000 live births (95% CI 9-13). After age-adjustment, Asians were more likely to develop complete mole (RR 2.3 95% CI 1.4-3.8, p < 0.001) but less likely to develop partial mole (RR 0.2; 95% CI 0.04-0.7, p = 0.02) than whites. Blacks were significantly less likely than whites to develop partial mole (RR 0.4; 95% CI 0.2-0.8, p = 0.01) but only marginally less likely to develop complete mole (RR 0.6; 95% CI 0.3-1.0, p = 0.07). Hispanics were less likely than whites to develop complete mole (RR 0.4; 95% CI 0.2-0.7, p = 0.002) and partial mole (RR 0.4; 95% CI 0.2-0.9, p = 0.02). Conclusion. Race/ethnicity is a significant risk factor for both complete and partial molar pregnancy in the northeastern United States. (C) 2016 Elsevier Inc. All rights reserved.