INCREASED RISK OF PLACENTA PREVIA AMONG WOMEN OF ASIAN ORIGIN

Objective: To investigate the frequency of placenta previa among Asian women. Methods: We conducted a population-based case-control study us ing Washington state birth certificate data from 1984-1987. Our study population included 810 women with pregnancies complicated by placenta previa and 2917 randomly selected controls. Unconditional logistic re gression was used to estimate odds ratios (OR) and their 95% confidenc e intervals (CI), and interaction terms were used to examine effect mo dification. potential confounding by maternal age, gravidity and parit y, maternal smoking during pregnancy, and a history of abortion or ces arean delivery was adjusted for in the analysis. Results: The frequenc y of placenta previa during the study period was 3.3 per 1000 live bir ths. Women of Asian origin were 86% more likely (OR 1.86, 95% CI 1.38- 2.51) to have a delivery complicated by placenta previa than were whit e women. This association was stronger among women without a previous live birth (OR 2.51, 95% CI 1.57-4.01) than those who previously had e xperienced a live birth (OR 1.50, 95% CI 1.01-2.25). Conclusion: Asian women residing in the United States are at increased risk of placenta previa. If confirmed by others, our results suggest that obstetrician s should consider meticulous ultrasound evaluations during pregnancy t o rule out the presence of placenta previa in Asian-American women.