Positive vaginal culture at rescue cerclage predicts subsequent preterm delivery

This retrospective case-control study is aimed to extract predictors of preterm delivery after rescue cerclage.

We collected the data from all the pregnant women who underwent rescue cerclage before 26⁺⁰ gestational weeks at our facility between July 2006 and July 2016. These women were divided into "delivery at <34 weeks" group (n = 12) and "delivery at ≥34 weeks" group (n = 12). Multiple factors that had been detected at the time of cerclage were compared between these two groups.

"Gestational weeks at cerclage ≥23" and "positive vaginal culture at cerclage" were significantly more prevalent in the "delivery at <34 weeks" group than in the "delivery at ≥34 weeks" group. "Prolapsed membranes at cerclage" tended to be more prevalent in the "delivery at <34 weeks" group than in the "delivery at ≥34 weeks" group. "Positive vaginal culture at cerclage" was the only independent risk factor associated with eventual preterm delivery before 34 gestational weeks.

Simple aerobic bacterial culture of the vaginal swab sampled at the time of cerclage could be used as a reliable test to predict subsequent preterm delivery before 34 gestational weeks.