OBJECTIVES: To investigate the prevalences of reproductive tract infections (RTI)/sexually transmitted infections (STI) among married women in a rural district of Vietnam, and analyse the influence of socioeconomic, sociodemographic, and other determinants possibly related to RTI/STI. METHODS: A community-based cross-sectional study. Married women aged 18-49 years (n = 1012) were interviewed and underwent a gynaecological examination. Specimens were collected for laboratory diagnosis of chlamydia, gonorrhoea, trichomonas, bacterial vaginosis (BV), candidiasis, hepatitis B, HIV, and syphilis. RESULTS: In total, 37% of the women were clinically diagnosed with an RTI/STI. Aetiologically confirmed RTI/STI was identified in 39% of the women (including 6% with STI). Endogenous infections were most prevalent (candidiasis 26%, BV 11%) followed by hepatitis B 8.3%, Chlamydia trachomatis 4.3%, Trichomonas vaginalis 1%, Neisseria gonorrhoeae 0.7%, genital warts 0.2%, and HIV and syphilis 0%. Fifty per cent of the STI cases were asymptomatic. Younger age and intrauterine devices were significantly associated with an increased risk of BV. Determinants of candidiasis were vaginal douching, high education level and low economic status, whereas a determinant of chlamydia was high economic status. Outmigration of the husband was associated with an increased risk of hepatitis B surface antigen seroposivity among women. CONCLUSIONS: RTI/STI were prevalent among married women in a rural population of Vietnam. Syndromic algorithms should be consistently supplemented by risk assessment in order to reduce under and overtreatment. Microscopic diagnosis could be applied in primary care settings to achieve more accurate diagnoses. The promotion of health education aimed at reducing RTI/STI prevalences is an important tool in STI/HIV control programmes. Vaccination to prevent hepatitis B for migrants should be considered.