Cervical Insufficiency

Cervical insufficiency is the failure of the cervix to stay closed as a pregnancy grows. The cervix opens without pain. The pregnancy is then lost or delivered early, in the second trimester. The problem is structural. It can follow injury from earlier cervical surgery or a difficult delivery. Often no cause is found.

History and cervical length on ultrasound carry the diagnosis. A stitch placed around the cervix, called a cerclage, is the repair. One meta-analysis studied women carrying one baby, an earlier spontaneous preterm birth and a short cervix. Cerclage and vaginal progesterone looked equally effective, though no trial compared them directly.¹

A 1987 review placed this cause behind about one in four repeated pregnancy losses.² Loss in the second trimester deserves a search for a cause.