Objective: To estimate the rate of spontaneous preterm delivery and preterm premature rupture of membranes (PROM) in women with cervical intraepithelial neoplasia (CIN) 3.
Methods: This retrospective cohort analysis was performed on routinely collected Scottish national data. The exposed cohort comprised all women with CIN3; the unexposed cohort were women with no record of CIN. Further comparisons were made within the exposed cohort based on the type of treatment they had for CIN3. The primary outcomes were spontaneous preterm delivery and preterm PROM in their first pregnancies.
Results: Women with CIN3 were significantly more likely to have spontaneous preterm deliveries (11% compared with 6%, odds ratio [OR] 1.52, 95% confidence interval [CI] 1.29-1.80, P<.001) and preterm PROM (8% compared with 6%, OR 1.27, 95% CI 1.09-1.48, P=.001) as compared with the unexposed population. These differences were not seen between the different treatment groups within the exposed cohort.
Conclusion: Women with CIN3 have higher rates of spontaneous preterm delivery and preterm PROM than do those in the general population. Loop electrosurgical excision procedure did not alter these pregnancy complication rates. Women should be counseled adequately before treatment but should be reassured regarding the treatment of CIN on the risk of preterm delivery.
Level of evidence: II.