Pregnancy outcome after loop electrosurgical excision procedure for the management of cervical intraepithelial neoplasia

Previous studies have shown conflicting results on the outcome of pregnancy following loop electrosurgical excision procedure (LEEP). The purpose of this study was to evaluate whether LEEP affects the outcome of pregnancy after 20 weeks' gestation.

This is a matched cohort study of all women who had a LEEP for a biopsy-confirmed cervical intraepithelial neoplasia (CIN) in between December 1995 and December 2000 and subsequently delivered (after 20 weeks' gestation) at the University Hospital of Northern Norway. Women who had an ectopic pregnancy or an abortion (spontaneous or induced) following LEEP were excluded from analysis. Two controls matched for the date of delivery, age, parity, previous obstetric history and smoking habit were identified for each case using routinely entered data from the birth register. The main outcome measures were the duration of pregnancy and birth weight. Other variables recorded included the grade of cervical dysplasia, size of the electrosurgical loop, age, parity, pregnancy complications, mode of delivery, and perinatal outcome.

Of a total of 428 women of reproductive age who had LEEP performed during the study period, 89 had a pregnancy after the procedure. Ten women were excluded (three ectopic pregnancies, two induced abortions and five spontaneous abortions) from the study. Data from 79 women whose pregnancies progressed beyond 20 weeks and 158 matched controls were analysed. The mean age at the time of LEEP was 27 (range 19-36) years. The histological diagnosis was normal in 3 (3.8%), CIN1 in 5 (6.3%), CIN2 in 18 (22.8%), and CIN3 in 53 (67.1%) of the cases. Overall, mean gestation at delivery (38.3 vs. 39.1 weeks), mean birth weight (3,412 vs. 3,563 g), prevalence of preterm birth (11.4% vs. 10.8%) and low birth weight (10.1 vs. 5.1%) were not significantly different among the cases and controls. But when a relatively large loop (25 mm) had been used, the risk of preterm delivery (odds ratio 4.0) and low birth weight (odds ratio 14.0) was significantly higher than in controls. Pregnancy complications occurred more frequently (20 vs. 7%; p=0.006) among the cases than the controls.

LEEP in women with CIN did not significantly increase the risk of low birth weight or preterm birth in subsequent pregnancy in comparison to their controls, except when the size of electrosurgical loop was relatively large. However, the prevalence of pregnancy complications was significantly higher after LEEP.