title: Increased risk of placenta previa among women of Asian origin.
abstract: OBJECTIVE
  To investigate the frequency of placenta previa among Asian women.
  
  
  METHODS
  We conducted a population-based case-control study using 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 regression was used to estimate odds ratios (OR) and their 95% confidence intervals (CI), and interaction terms were used to examine effect modification. Potential confounding by maternal age, gravidity and parity, maternal smoking during pregnancy, and a history of abortion or cesarean delivery was adjusted for in the analysis.
  
  
  RESULTS
  The frequency of placenta previa during the study period was 3.3 per 1000 live births. 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 white 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 experienced a live birth (OR 1.50, 95% CI 1.01-2.25).
  
  
  CONCLUSIONS
  Asian women residing in the United States are at increased risk of placenta previa. If confirmed by others, our results suggest that obstetricians should consider meticulous ultrasound evaluations during pregnancy to rule out the presence of placenta previa in Asian-American women.
authors.affiliation: Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.
authors.forename: V M
authors.initials: VM
authors.lastname: Taylor
authors.forename: S
authors.initials: S
authors.lastname: Peacock
authors.forename: M D
authors.initials: MD
authors.lastname: Kramer
authors.forename: T L
authors.initials: TL
authors.lastname: Vaughan
mesh_terms: D000028:Abortion, Induced / Q000009:adverse effects; D000328:Adult; D001213:Asian; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008423:Maternal Age; D010298:Parity; D010923:Placenta Previa / Q000208:ethnology* / Q000209:etiology; D011247:Pregnancy; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D014861:Washington / Q000453:epidemiology