Cervical cerclage for preterm birth prevention in twin gestation with short cervix: a retrospective cohort study

ABSTRACT Objective To determine if cervical cerclage reduces the rate of spontaneous early preterm birth in cases of dichorionic–diamniotic (DCDA) twin gestation with an ultrasound‐detected short cervix. Methods This was a retrospective cohort study of 40 consecutive DCDA twin gestations at Saint Peter's University Hospital from November 2006 to November 2014 in which cervical cerclage was performed for an ultrasound‐determined cervical length of 1–24 mm at 16–24 weeks' gestation. The cases were matched with 40 controls without cerclage for cervical length and gestational age at cervical assessment. The primary outcome measure was spontaneous birth < 32 weeks. Results There was no difference between the two groups in maternal age, body mass index (BMI), cigarette smoking, use of in‐vitro fertilization (IVF), parity and prior spontaneous preterm birth. There were more Caucasian women among the controls compared with cases. In the cases, compared with controls, spontaneous delivery < 32 weeks was significantly less frequent (20.0% vs 50.0%; relative risk, 0.40 (95% CI, 0.20–0.80)). In the prediction of spontaneous delivery < 32 weeks, logistic regression analysis demonstrated that the risk was reduced with the insertion of cervical cerclage (odds ratio, 0.22 (95% CI, 0.058–0.835); P = 0.026), corrected for maternal age, BMI, racial origin, cigarette smoking, IVF, parity and previous preterm birth. Conclusion In DCDA twin gestation with a short cervix, treatment with cervical cerclage may reduce the rate of early preterm birth. The findings suggest the need for adequate randomized controlled trials on cerclage in twin gestations with a short cervix. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.