Laser vaporization of the cervix is associated with an increased risk of preterm birth and rapid labor progression in subsequent pregnancies

Purpose: Laser vaporization of the cervix is an established method of treating cervical intra-epithelial neoplasia, but its effect on subsequent pregnancies remains controversial. The aim of this study was to investigate pregnancy outcomes after laser vaporization. Methods: We conducted a retrospective study involving women who delivered live singletons between 2012 and 2019 in a tertiary hospital. The risks of adverse pregnancy outcomes after laser vaporization of the cervix were assessed using a multivariate regression model. The primary outcome was the adjusted odds ratio for preterm births. We also evaluated the course of labor progression, duration of labor, risk of emergency cesarean deliveries, and the risk of cervical laceration as secondary outcomes. Results: In total, 3359 women were analyzed in this study. The risk of preterm birth was significantly higher in pregnancies after laser vaporization of the cervix (adjusted odds ratio [AOR] 1.84, 95% confidence interval [95% CI] 1.06–3.20; p = 0.030). The duration of the first stage of labor was significantly shorter in the post-treatment group (median 255 min vs. 355 min; p = 0.0049). We did not observe significant differences in the duration of the second stage of labor (median 21 min vs 20 min; p = 0.507) or the rates of other obstetric events, including emergency cesarean deliveries (AOR 0.736; 95% CI 0.36–1.50; p = 0.400) and cervical laceration (AOR 0.717; 95% CI 0.22–2.35; p = 0.582). Conclusion: Laser vaporization of the cervix is associated with an increased risk of preterm births and a shorter duration of the first stage of labor in subsequent pregnancies. Careful consideration is necessary when selecting a method of treatment for the uterine cervix of patients wishing future pregnancies.