Preterm delivery after surgical treatment for cervical intraepithelial neoplasia.

Abstract

To study whether a treatment of cervical intraepithelial neoplasia (CIN) is associated with an adverse outcome in the subsequent pregnancies. This study is a register-based retrospective cohort study from Finland. National data of 25,827 women having a surgical treatment of the cervix for CIN in 1986-2003 and their 8,210 subsequent singleton births in 1987-2004 were studied. Main outcome measures were preterm birth rate, low birth weight rate, and perinatal mortality rate. The risk of any preterm delivery (less than 37 weeks of gestation), especially the risk of very preterm delivery (28-31 weeks of gestation), and extremely preterm delivery (less than 28 weeks of gestation) was increased after cervical conization (relative risk [RR] 1.99, 95% confidence interval [CI] 1.81-2.20; RR 2.86, 95% CI 2.22-3.70; and RR 2.10, 95% CI 1.47-2.99, respectively). After cervical ablation, the risk of preterm delivery was also increased. The risk of low birth weight and perinatal death was increased after conization (RR 2.06, 95% CI 1.83-2.31 and RR 1.74, 95% CI 1.30-2.32, respectively). Adjusting for maternal age, parity, and maternal smoking did not affect our results. Any treatment for CIN, including loop electrosurgical excision procedure, increases the risk of preterm delivery. It is important to emphasize this when treating young women with CIN. II.