Fifteen women with diminished fertility as a result of congenital uterine anomalies were treated by cervical suture (cerclage) in the 11th-12th week of pregnancy without surgical correction of the uterine anomaly. None of these women had either clinical or radiological evidence of cervical incompetence. As a result of the treatment, 13 of the women delivered live full-term mature infants. None of the women aborted, only two women delivered prematurely, and both infants were alive and well. Comparison of these good results to the very poor outcome of previous pregnancies in these women points to a distinct advantage to be gained by cervical suture. As a result of this experience, we recommend cervical suture in cases of diminished fertility as a result of congenital uterine anomaly. We recommend that the suture be performed before considering surgical repair of the anomaly and irrespective of lack of evidence of cervical incompetence. Only in cases where cervical suture is unsuccessful, would we recommend surgical correction according to the accepted techniques.