Pregnancy incidence and outcome before and after cervical intraepithelial neoplasia: a retrospective cohort study.

Ilkka Kalliala,Pekka Nieminen,Tadeusz Dyba,Mervi Halttunen,Ahti Anttila

doi:10.1002/cam4.300

Ilkka Kalliala, Pekka Nieminen + Show 3 more

Open Access

https://doi.org/10.1002/cam4.300

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Journal: Cancer medicine	Publication Date: Aug 21, 2014
Citations: 15	License type: CC BY 3.0

Affiliation: University of Helsinki, Finnish Cancer Registry

Abstract

We performed a retrospective cohort study of 3530 women treated for cervical intraepithelial neoplasia (CIN) in Helsinki University Central Hospital, Finland, to investigate whether CIN treatment itself affects pregnancy incidence and outcome. We estimated the incidence of live births, miscarriages, extrauterine pregnancies, molar pregnancies, and termination of pregnancies (TOPs) before and after CIN treatment using nationwide registers. Women were followed up until death, emigration, sterilization, or the end of 2004. The comparison of incidence of pregnancy outcomes before and after the treatment was estimated by calculating hazard ratios (HRs) with conditional Poisson regression. After 76,162 woman-years of follow-up, the incidence of any pregnancy remained constant over CIN-treatment, HR 1.02 and 95% confidence interval (CI) 0.97–1.08, but the incidence of the first pregnancy was significantly elevated after treatment, HR 1.13, and 95% CI 1.03–1.23. The incidence of live births was significantly elevated after treatment, HR 1.08 and 95% CI 1.01–1.15. Incidence of miscarriages, TOPs, extrauterine pregnancies, and molar pregnancies was not elevated. TOPs was significantly increased in the first pregnancy, HR 1.40, 95% CI 1.15–1.72 and after treatment by the loop electrosurgical excision procedure (LEEP), HR 1.36, 95% CI 1.15–1.60. CIN treatment did not reduce pregnancy incidence and women had more live births after than before CIN treatment. TOPs was more common in the first pregnancy or after treatment by LEEP. We encourage research on the psychosocial consequences of CIN treatment also in other countries and settings.

Highlights

Evidence linking cervical intraepithelial neoplasia (CIN) treatments, like cervical conization, to later increase in preterm deliveries, low birthweight, and perinatal mortality is extensive [1,2,3]
The largest study so far showed that the incidence of pregnancy or live birth was higher among the CIN-treated women compared to the age-matched reference population, and the risk of induced abortion and extrauterine pregnancy was higher in CIN patients than the reference cohort [4]
The incidence of any pregnancy was similar after and before the CIN treatment, hazard ratios (HRs) 1.02 and 95% confidence interval (CI) 0.97–1.08, but the incidence of the first-ever pregnancy was significantly elevated after treatment, HR 1.13 and

Summary

Introduction

Evidence linking cervical intraepithelial neoplasia (CIN) treatments, like cervical conization, to later increase in preterm deliveries, low birthweight, and perinatal mortality is extensive [1,2,3]. Effects of the cervical conization itself on the incidence of pregnancies, live births, and other types of pregnancies are less clear. The largest study so far showed that the incidence of pregnancy or live birth was higher among the CIN-treated women compared to the age-matched reference population, and the risk of induced abortion and extrauterine pregnancy was higher in CIN patients than the reference cohort [4]. Women with CIN differ from the general population in several significant ways: they smoke more, have more sexually transmitted infections, are more often multiparous, have more sexual partners during their lives, and they are younger at sexual debut [5]—all these factors are capable of affecting fertility as well.

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