Long-term mortality in women treated for cervical intraepithelial neoplasia M Jakobsson, a M Gissler, b,c J Paavonen, a A-M Tapper a a Department of Obstetrics and Gynaecology, University Hospital, Helsinki, Finland b STAKES National Research and Development Centre for Welfare and Health, Helsinki, Finland c Nordic School of Public Health, Gothenburg, Sweden Correspondence: Dr M. Jakobsson, Department of Obstetrics and Gynaecology, University Hospital, Helsinki, Finland. Email maija.jakobsson@fimnet.fi Accepted 30 December 2008. Objective The objective of this study was to study whether women surgically treated for cervical intraepithelial neoplasia (CIN) have increased mortality later in life. We also wanted to study whether pregnancy beyond 22 weeks post-treatment affects the risk. Design Register-based retrospective cohort study from Finland. Setting National data of the Hospital Discharge Register and the Cause-of-Death Register during 1986–2003. Population A total of 25 827 women who had surgical treatment for CIN during 1986–2003. Methods We calculated standardised mortality ratios (SMRs) by dividing the numbers of observed deaths (until 31 December 2006) by the numbers of expected deaths. Main outcome measures SMRs for different causes-of-death groups. Results The overall mortality increased by 17% after treatment for CIN, including increased risk of dying from all diseases and medical conditions (SMR 1.13, 95% CI 1.01–1.26), cancers (SMR 1.09, 95% CI 0.91–1.27) and injury deaths (SMR 1.31, 95% CI 1.03–1.58). As expected, the mortality from cervical cancer was high (SMR 7.69, 95% CI 4.23–11.15). Women who had delivered post-treatment tended to have decreased overall mortality (SMR 0.78, 95% CI 0.52–1.04) and decreased disease mortality (SMR 0.63, 95% CI 0.37–0.90). However, the mortality rate was significantly increased for women who had subsequent preterm delivery (SMR 2.51, 95% CI 1.24–3.78). In this subgroup, there was a tendency of increased mortality from diseases of the circulatory system, alcohol-related causes and injury deaths. Conclusions Mortality rate was increased after surgical treatment for CIN. However, women who had delivered post-treatment had decreased overall disease mortality rate. Subsequent preterm delivery may be a risk marker for increased long-term mortality. Keywords Conisation, delivery post-treatment, mortality, treat- ment for CIN. Please cite this paper as: Jakobsson M, Gissler M, Paavonen J, Tapper A-M. Long-term mortality in women treated for cervical intraepithelial neoplasia. BJOG 2009;116:838–844. Introduction We have previously studied a cohort of women treated for cervical intraepithelial neoplasia (CIN) and demonstrated that any cervical surgical treatment for CIN is associated with pre- term delivery. 1,2 There is strong evidence that women treated for CIN3 are at increased risk of developing invasive cervical, vaginal or anal cancer. 3,4 Increased risk of smoking-related cancers has also been demonstrated. 5 Women with CIN are generally young, and CIN lesions are caused by sexually trans- mitted high-risk human papillomavirus (HPV) types. Risk- taking behaviour also increases the risk for other sexually transmitted infections. Thus, our hypothesis was that these factors may predispose to increased morbidity and mortality. The link between history of CIN, delivery and mortality for other causes has not been systematically studied. In general, women with recent delivery have lower mortality rates. 6,7 However, women with preterm delivery are at increased risk for cardiovascular diseases. 8–11 We had an opportunity to use Finnish register data to find out whether women treated for CIN have increased mortality later in life. We also studied mortality among women with subsequent term or preterm delivery. Materials and methods The study population consisted of 25 827 women of repro- ductive age (15–49 years) who had been surgically treated for CIN during 1986–2003. These women were identified from the Hospital Discharge Register (HDR), maintained by STAKES (National Research and Development Centre for Welfare and Health). The HDR collects information on all 838 ª 2009 The Authors Journal compilation ª RCOG 2009 BJOG An International Journal of Obstetrics and Gynaecology DOI: 10.1111/j.1471-0528.2009.02115.x www.blackwellpublishing.com/bjog Epidemiology