SENTINEL SURVEILLANCE OF CHLAMYDIA-TRACHOMATIS INFECTION IN WOMEN TERMINATING PREGNANCY

Aims: To evaluate demographic characteristics of women terminating the ir pregnancy for sentinel surveillance of Chlamydia trachomatis infect ion and to report changing prevalences of C trachomatis over time with in this study population. Design: Screening for C trachomatis in women seeking induced abortion was introduced in 1984 at the Department of Gynecology, Regional Hospital, Trondheim, Norway. Over the study years our department has used a preceded medical record covering sociodemog raphic, medically relevant data, also recording outcome of the C trach omatis test. Throughout the study the Department of Microbiology appli ed cell culture, enzyme Immunoassay, and, during the most recent years a nucleic acid test to identify C trachomatis. Statistical methods: C hi square test for linear trend and unconditional logistic regression. Results: Over the study period, women having induced abortion were ch aracterised by being most often single and more often at younger age. The overall age-adjusted prevalence of C trachomatis declined from 9.2 % in 1985 to 3.6% in 1995, the major decline occurring from 1987 to 19 91, and affected all age-groups simultaneously. There was a 60% decrea se in odds ratio of having a C trachomatis infection from 1985 to 1991 , and the crude and the adjusted odds ratios did not differ for any ye ar examined. Conclusion: Women deciding on pregnancy termination have demographic characteristics that identify high-risk groups for C trach omatis infection. Despite these characteristics, which were relatively constant over the study period, the study population changed from bei ng a high- to a low-prevalence population of C trachomatis.