Objective: To assess pregnancy outcome after conisation.
Design: Retrospective cohort study.
Setting: Belgium, data from a university hospital.
Population: Fifty-five pregnancies in 34 women after conisation, and 55 pregnancies in 54 women without a history of conisation or cervical intraepithelial neoplasia (CIN).
Methods: Hospital data were reviewed and questionnaires were collected from 599 women who had a conisation in a 5-year period, among whom subsequent pregnancies were identified. The control group consisted of matched pregnancies of women without a history of conisation.
Main outcome measures: Gestational age at delivery, neonatal biometry, neonatal condition at birth.
Results: Numbers of sexual partners (4.6 +/- 3.4 SD versus 2.5 +/- 2.5 SD) and ex-smokers were significantly higher in the study group compared with the control group. Gestational age at delivery (266 +/- 2 days versus 274 +/- 9 days), neonatal head circumference (33.9 +/- 2.5 cm, versus 34.6 +/- 2.5 cm) and birthweight (3088 +/- 754 g versus 3381 +/- 430 g) were significantly lower in the study group compared with the control group. Numbers of preterm [<37 weeks; 14/55 (25%) versus 2/55 (4%); P = 0.002] and severe preterm (<34 weeks; 6/55 (11%) versus 0/55 (0%); P = 0.031] deliveries in the study group were significantly higher. There were no cases of perinatal mortality.
Conclusions: Conisation affects obstetrical outcome after conisation for CIN. Babies tend to be born earlier and are smaller. It is not clear whether this is related to the procedure or to factors linked with CIN.