Cervical conisation and the risk of preterm delivery: a retrospective matched pair analysis of a German cohort.

PURPOSE: Since the routine screening program for cervical dysplasia by Pap smear was established in the early 1970s, the rate of cervical cancer has continually dropped. Even if a high percentage of cervical dysplasia shows spontaneous restitution, the only effective therapy for persisting cervical dysplasia is local ablation or excision which might be associated with an increased risk of preterm delivery in subsequent pregnancies. However, data from German patients are missing, so the aim of this study was to evaluate the risk of preterm delivery and associated risks in a cohort of patients who had undergone cervical conisation previous to their pregnancies. METHODS: A total of 144 patients with conisation and subsequent pregnancy were identified. They were compared regarding week of delivery and preterm birth, fetal birth weight, fetal outcome and birth procedure (spontaneous delivery, vacuum extraction, primary and secondary cesarean section) with their matched partners. RESULTS: 135 patients with singleton pregnancies and their matched partners were evaluated in the final analysis. The mean age was 33.5 years. Comparing the case and control group we reached significant different results for week of delivery, but not preterm birth defined as birth prior to 37 weeks of gestation. CONCLUSIONS: Within this German cohort cervical conisation did not increase the risk for preterm birth, cesarean section or poor fetal outcome. We therefore conclude that cervical conisation is an appropriate method to treat women with cervical dysplasia also at childbearing age when prevention of cervical cancer is needed.