Reported condom use is not associated with incidence of sexually transmitted diseases in Malawi

OBJECTIVES: To establish frequency of reported condom use and validate reliability of self-reporting among urban women in Malawi. DESIGN: Cross-sectional survey in antenatal women in 1989 and 1993. Prospective study in cohort first surveyed in 1989. METHODS: A total of 6561 women in 1989 and 2460 women in 1993 answered questions about condom use and sexual activity, had a physical examination and were screened for HIV. A subset of women from the 1989 screening were administered a questionnaire and tested for syphilis, Neisseria gonorrhoeae and Trichomonas vaginalis infections every 6 months. RESULTS: Although between the two cross-sectional studies intermittent condom use increased from 6 to 15% (P < 0.001) with no difference according to HIV infection, consistent use was reported by less than 1%. In the prospective study, women reported a higher condom use at any visit than either group assessed cross-sectionally. Consistent condom use peaked at 62% in the first 6 months, but declined to as low as 8% in the second year of follow-up. Condom use at each visit, either intermittent or consistent, was higher in HIV-seropositive than HIV-seronegative women. Overall, the incidence of gonorrhea, trichomoniasis and syphilis did not decline in women reporting consistent condom use. CONCLUSIONS: In prospectively followed women reports of consistent condom use was substantially higher than in cross-sectional surveys, but rapidly decreased over time, irrespective of HIV status. The presence of new sexually transmitted diseases suggests that this population of urban women overreports condom use or underreports sexual activity, or both. Intensive and sustained education is needed to achieve consistent condom use. Biologic markers of sexual activity are useful in interpreting reported condom use.