Background FSWs are a high-risk population group for the transmission and acquisition of STIs and HIV. This research investigated socio-demographic characteristics and risk behaviours among FSWs in Ba Ria – Vung Tau, Vietnam.

Methods Data were collected using a cross-sectional survey of 420 direct/indirectly employed FSWs between January–May, 2014, from 2 cities/6 districts in Ba Ria – Vung Tau. FSWs were interviewed using a structured questionnaire and biological samples taken and tested for STI/HIV. Data were entered (Epidata 3.1) and analysed (SPSS 20.0) using univariate and multivariate analyses to investigate the associations between STIs and risk-related factors.

Results 166 direct and 254 indirect FSWs participated in the survey, with a median age of 27 years, within a range of 18–43 years. Many (43.3%) had minimal education (grade 5 or less). Most claimed religious affiliation (90.5%) and 91.7% were of Kinh ethnicity. At 63.1%, the unemployment rate before becoming FSWs was high. There were significant differences between direct/indirect types of FSWs in terms of: education levels (OR = 2.46, 95% CI: 1.65–3.67, p = 0.001); marital status, including married or cohabitating (OR = 2.14, 95% CI: 1.43–3.207, p = 0.001); unemployment before becoming FSWs (OR = 2.36, 95% CI: 1.54–3.63, p = 0.001); low income ≤ A$200 (OR = 3.74, 95% CI: 1.83–7.65, p = 0.001); and number of paying clients in the last month >15 (OR = 24.88, 95% CI: 14.73–42.01, p = 0.001). Inconsistent condom use with regular and new clients was 21.8% and 15.2% respectively. Most (89.0%) FSWs performed oral sex, also a high proportion (82.4%) of them consumed alcohol. Nearly half (48.3%) have had sex when drunk. Regarding drug use, 23.4% FSWs have used drugs and 26.1% have clients who use or inject drugs.

Conclusions FSWs in Vietnam need targeted intervention programs and improved services to prevent HIV and STIs infection. Administrative and political support for improved health education and services are required to prevent the epidemic from spreading.