Background: In Australia, reported rates of Chlamydia trachomatis infection have been rising progressively since the mid-1990s. Opportunistic testing of sexually active young women attending clinical services for other reasons has already been implemented in a number of other countries. Aims: To help guide chlamydia testing of women, this study aimed to establish factors predictive of chlamydial infection in an Australian clinical setting. Methods: Women attending a sexual health service in Sydney who tested positive for C. trachomatis by polymerase chain reaction and who did not have any concurrent urogenital infections (w = 170) were compared with chlamydia-negative controls (n = 170). Factors independently associated with chlamydia were determined using logistic regression. Results: Although they were present in only a minority of infected women, symptoms of dysuria [adjusted odds ratio (AOR) = 3.2 (95% CI: 1.2-9.1), P = 0.03] and postcoital bleeding [AOR = 2.7 (95% CI: 1.0-7.1), P < 0.05] were each independently associated with chlamydia. Symptoms of vaginal discharge (P = 0.3), abdominal pain (P = 0.2), or intermenstrual bleeding (P = 0.1) did not help to discriminate between infected and uninfected women. The following factors were independently associated with chlamydia: younger age (P = 0.003); being overseas-born [AOR = 2.3 (95% CI: 1.3-4.0), P = 0.005]; sex with a partner from overseas [AOR = 2.0 (95% CI: 1.3-12.3), P = 0.01]; and sex with a partner known or suspected to be chlamydia-infected [AOR = 7.4 (95% CI: 3.6-15.0), P < 0.001]. Conclusions: Chlamydia testing is clinically indicated in sexually active young women with dysuria, postcoital bleeding or contact with a suspected chlamydia-infected partner. Consideration should be given to enhanced screening programs for travelling and migrant men and women in Australian cities.

Sexually transmitted infections Screening Chlamydia trachomatis Women

urban population Australia mass screening abdominal pain human risk assessment middle aged Odds Ratio health service Confidence Intervals menstruation probability priority journal controlled study vagina discharge Humans Severity of Illness Index female prediction risk factor bleeding polymerase chain reaction Incidence Article Retrospective Studies Sexually Transmitted Diseases, Bacterial major clinical study adult migration age distribution Case-Control Studies Reference Values Chlamydia Infections chlamydiasis Chlamydia trachomatis dysuria