Objective: The purpose of this study was to examine how vaginal douching may influence risk of preterm birth.
Study design: We conducted a hybrid cohort study on risk factors for preterm birth. African American women who resided in Baltimore City, Maryland, were enrolled prenatally if they received prenatal care at 1 of 4 Johns Hopkins Medical Institution prenatal clinics or were enrolled after delivery if they delivered at the Johns Hopkins Medical Institution with late, none, or intermittent prenatal care. Interview data were collected on 832 women delivering singleton infants between March 2001 and July 2004.
Results: The preterm birth rate was 16.4%. After adjustment for several potential confounders, those covariates that were associated with either vaginal douching or preterm birth in our sample or that were identified as confounders in the literature, vaginal douching 6 months before pregnancy, and < 3 times per month (prevalence ratio, 0.63; 95% CI, 0.42-0.95) were associated with a reduced risk of preterm delivery. Douching during pregnancy was associated with a trend toward increased risk of preterm birth (prevalence ratio, 1.64; 95% CI, 0.97-2.76).
Conclusion: Vaginal douching effects on the risk of preterm birth depend on the timing of the exposure. Douching in the 6 months before pregnancy, but not during pregnancy, appears to protect against preterm birth.