Sexually transmitted infections and bacterial vaginosis in women of child-bearing age in Antananarivo, Madagascar: prevalence and risk factors from a cross-sectional study.

Background: Recent data on sexually transmitted infections (STIs) and bacterial vaginosis (BV) in the general population of Madagascar is scarce. Our objective is to estimate the Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Trichomonas vaginalis (TV), Mycoplasma genitalium (MG), and BV prevalence among women and to determine associated risk factors.

Methods: We recruited women aged 18-45 years consulting at a hospital in Antananarivo in a cross-sectional study. We collected socio-demographic and behavioral data. Vaginal swabs were collected for each individual. STIs were detected by qPCR and BV using the Nugent score. We explored factors associated with having an STI using logistic regressions.

Results: Of the 501 recruited women, 242 (48%) were married. Only one woman in three ever used condoms. The prevalence of CT was 11.8% (95% Confidence Interval: 9.0, 14.6), NG: 4.2% (2.4, 5.9), TV: 14.8% (11.7, 17.9), MG: 8.2% (5.8, 10.6), and BV: 39.6% (35.3, 43.9). Factors associated with an STI were having sex in exchange for favors (adjusted Odds Ratio (aOR): 4.25, 95%CI: 1.27, 16.6), BV (aOR: 2.14, 95%CI: 1.34, 3.47) or intermediate vaginal microbiota (aOR: 2.10, 95%CI: 1.19, 3.72), and being in a non-marital relationship compared to married (aOR: 1.86, 95%CI: 1.16, 2.98).

Conclusions: To address the high prevalence of STIs, prevention programs should target women who are more likely to engage in sex in exchange for favors and empower them with negotiation skills on condom use. Given the elevated prevalence of dysbiosis and its association with STIs, it is crucial to prioritize research efforts toward a comprehensive understanding of this relationship.