Transabdominal isthmic cerclage for the treatment of incompetent cervix.

During the period from 1973 to 1980 transabdominal isthmic cerclage was performed on 32 patients. Twenty-nine patients experienced 35 pregnancies. In 23 cases (79%) the diagnosis was based on one or several second-trimester abortions. In the remaining 6 cases the diagnosis was based on clinical findings of an abnormal cervix. Both groups had fetal loss in first and third trimester. The operation was performed before pregnancy or during pregnancy up to the 14th week. The fetal salvage rate rose from 12% to 91.4%, and the prematurity rate was 6.7% after operation. Only one pregnancy was terminated prematurely, due to forcible labor.