Cerclage Plus Progesterone vs Progesterone Alone in Twin Short Cervix

Women with twin pregnancy in which one or both fetuses are diagnosed with a major structural or congenital abnormality that is likely to influence the composite adverse neonatal outcome.

Women with a monochorionic monoamniotic twin pregnancy

A monochorionic twin pregnancy with twin-to-twin transfusion syndrome before or at the time of inclusion.

Patients have indications for vaginal cerclage: Recurrent late miscarriage (from 14 weeks) or preterm birth occurring two or more times.