Association between cervical conization and pregnancy outcomes: A nationwide population-based cohort study

Cervical conization is the standard treatment for cervical intraepithelial neoplasia. However, its effects on pregnancy outcomes remain controversial. Using data from the Korean National Health Insurance System, this population-based retrospective cohort study evaluated the relationship between cervical conization and adverse pregnancy outcomes between 2006 and 2022. Altogether, 199,826 singleton primiparous women aged 19 years or older were included, of whom 18,602 had undergone conization prior to pregnancy. The adjusted odds ratios for obstetric complications were estimated using multivariable logistic regression. Conization was associated with an elevated risk of cervical incompetence (adjusted odds ratios [aOR] 3.15; 95% confidence interval [CI] 3.01-3.30), preterm labor (aOR 1.44), preterm premature rupture of membranes (aOR 1.67), placenta previa, gestational diabetes, and intrauterine growth restriction. The subgroup analysis revealed that women who underwent both conization and cerclage had substantially higher risks of preterm labor and preterm premature rupture of membranes than did those who did not receive cerclage. The results point to a heightened obstetric risk following cervical conization, emphasizing the need for tailored prenatal care and continued prospective investigation.