Cervical cerclage effective in high-risk twin pregnancies

Cervical cerclage used after a physical exam that showed evidence of dilation in the second trimester effectively reduced preterm birth and infant mortality in twin pregnancies, according to a study published in the American Journal of Obstetrics and Gynecology.

“For women with twin pregnancies and early signs of labor and cervix dilation, there was really very little we could offer,” Amanda Roman, MD, associate professor in the department of obstetrics and gynecology at Thomas Jefferson University in Philadelphia, said in a press release. “This study provides powerful evidence that there is an effective treatment we can use.”

Roman and colleagues conducted a parallel group, open-label randomized control trial at eight clinical centers from July 2015 to July 2019. The women who were included in the study had diamniotic twin gestations with asymptomatic cervical dilation of 1 cm to 5 cm and/or membranes visible in pelvic or speculum exams between 16 weeks and 24 weeks gestation.

Participants were randomly assigned to receive cerclage plus antibiotics and indomethacin or standard care.

PCPs removed patients’ cerclage during week 36 of gestation or earlier if they were experiencing acute vaginal bleeding, labor, premature rupture of membranes or if membranes prolapsed through the cerclage suture.

The researchers noted that the trial was stopped early after an interim analysis conducted by the Data Safety Monitoring Board found it would be unethical to continue due to the considerable difference in perinatal mortality between the cerclage and noncerclage groups.

A total of 30 women were enrolled in the study. Of those, 17 were assigned to receive cerclage and 13 were assigned to the noncerclage group. In the cerclage group, 14 women underwent cerclage procedure.

Roman and colleagues found the incidence of preterm birth before 34 weeks gestation was significantly lower in the cerclage group than the noncerclage group (RR= 0.71; 95% CI, 0.52-0.96)

In addition, the incidence of preterm birth was lower in the cerclage group compared with the noncerclage group before 32 weeks (RR = 0.65; 95% CI, 0.46-0.92), before 28 weeks (RR = 0.49; 95% CI, 0.26-0.89) and before 24 weeks (RR = 0.35; 95% CI, 0.16-0.75).

The mean gestational age at delivery was 29.05 ± 1.7 weeks in the cerclage group, compared with 22.5±3.9 weeks in the noncerclage group. Similarly, the mean interval from time of cervical dilation diagnosis to delivery was longer in the cerclage group at 8.3 ± 5.8 weeks than the noncerclage group at 2.9±3.0 weeks.

Roman and colleagues also determined the risk for perinatal mortality was significantly reduced among women who received cerclage (RR = 0.22; 95% CI, 0.1-0.5).

“We’ve already incorporated this cerclage into our practice and have been able to offer this to pregnant mothers with twins with great success,” Vincenzo Berghella, MD, director of the division of maternal and fetal medicine at Jefferson, said in the release. “These results have the potential to change practice and help many more women have healthy twin babies.”