[Relations between taking contraceptive pills, condom use and sexually transmitted disease history among female sex workers].
OBJECTIVE
The aim of this study was to analyze how taking contraceptive pills and condom use are related to each other, and their links to sexually transmitted disease (STD) history among female sex workers.


METHODS
A cross-sectional study was performed by means of a standardized questionnaire self-administered by sex workers who attended a STD Clinic in Osaka between 1st April, 1998 and 31st March, 1999. They came to the clinic for routine screening for STDs and HIV (Human Immunodeficiency Virus) infection, and for treatment. The responses of a total of 92 sex workers, who are basically expected to use condoms and identified themselves as "sex workers at bath houses", "sex workers in former red light districts", "sex massage providers on call" and "call girls" on the questionnaires, were analyzed.


RESULTS
The proportion of sex workers who were diagnosed with chlamydial infection either currently or over the previous year was higher among sex workers who answered they take contraceptive pills "regularly" (pill users) than in those who answered "irregularly" or "not" (non-pill users). This finding was statistically significant for those whose education was less than 12 years, whose professional career as a sex worker was 1 year or more, and whose average daily income was 50,000 yen (US$450) or more. Except for the group whose income was less than 50,000 yen, the proportion of sex workers in all groups who were diagnosed with chlamydial infection was greater, although the difference was not statistically significant, among pill users than among non-users. The proportion of sex workers who use condoms "regularly and correctly" was significantly higher for non-pill users than for those using the pills. Multiple logistic regression analysis showed that pill use was significantly related to condom "not or irregular or incorrect" use (Odds ratio: 4.43, CI 1.12-17.60). The proportion of sex workers with a chlamydial infection history was significantly lower with those using condoms "regularly and correctly" than in those who do not use condoms or employ them "irregularly or incorrectly" (Odds ratio: 0.08, CI 0.01-0.68).


CONCLUSIONS
This study showed the proportion of sex workers diagnosed with chlamydial infection to be higher among pill users than among non-users and the proportion of sex workers who use condoms "regularly and correctly" was higher among non-pill users than among users. These findings suggest that irregular, incorrect or non use of condoms among pill users may cause chlamydial infection.
Kimoto
K
K
Department of Social and Environmental Medicine, Osaka University Graduate School of Medicine F2.
D000293:Adolescent; D000328:Adult; D002690:Chlamydia Infections / Q000453:epidemiology / Q000209:etiology; D017280:Condoms / Q000706:statistics & numerical data*; D003271:Contraceptive Agents, Female / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D011477:Sex Work / Q000706:statistics & numerical data*; D012749:Sexually Transmitted Diseases / Q000453:epidemiology / Q000209:etiology
D003271:Contraceptive Agents, Female