The effect of postoperative vaginal progesterone in ultrasound-indicated cerclage to prevent preterm birth.

OBJECTIVES

To compare pregnancy outcomes according to the use of postoperative vaginal progesterone in patients who underwent ultrasound-indicated cerclage.

METHODS

This was a retrospective cohort study of 86 consecutive asymptomatic singleton pregnancies who had undergone cerclage because of incidentally found short cervical length under 20 mm through transvaginal ultrasound between 16°/7 and 246/7 weeks' gestational age. Outcomes were compared according to the use of vaginal progesterone after cerclage. Primary outcome measure was preterm delivery < 34 weeks of gestation.

RESULTS

(1) The frequency of preterm delivery < 34 weeks of gestation was significantly lower in patients with postoperative vaginal progesterone than those without (2.2 versus 18.4%, p = .021); (2) the median gestational age at delivery in the postoperative vaginal progesterone group was significantly longer than the control group (38.3 weeks (interquartile range, 37.5-39.1 weeks) versus 37.3 weeks (interquartile range 33.9-38.6 weeks), p = .020); (3) Multivariable logistic regression analysis demonstrated the use of vaginal progesterone after cerclage was found to be independently associated with decrease in preterm delivery before 34 weeks (Odds ratio 0.10; 95% confidence interval, 0.01-0.93) and 37 weeks (Odds ratio 0.24; 95% confidence interval, 0.07-0.85).

CONCLUSIONS

The use of vaginal progesterone was associated with lower rates of preterm birth before 34 and 37 weeks of gestation in women who underwent ultrasound-indicated cerclage placement.