Factors Associated with Risky Sexual Behaviour among Women Informal Cross-border Traders in Lusaka, Zambia

Background Women informal cross-border traders in Lusaka, Zambia, operate in highly mobile and economically vulnerable contexts that may heighten their exposure to risky sexual behaviour and HIV. This study examined the socio-demographic, migratory, and behavioural factors associated with risky sexual behaviour among women informal cross-border traders, focusing on identifying key predictors using a binary logistic regression approach. Methods A cross-sectional survey was conducted in 2019 among 499 women engaged in informal cross-border trade at the Common Market for Eastern and Southern Africa (COMESA) Market in Lusaka. Data were collected via a structured questionnaire capturing socio-demographic characteristics, sexual behaviour, mobility patterns, and social lifestyle factors. Binary logistic regression was used to identify determinants of risky sexual behaviour, with odds ratios (ORs) and 95% confidence intervals (CIs) reported. Results The majority of respondents (67.7%, n = 338) were classified as high-risk and 32.3% (n = 161) as low-risk. Behavioural factors were the strongest predictors of risky sexual behaviour. Women with two or more sexual partners were 14 times more likely to engage in risky sexual behaviour (OR = 14.57, 95% CI: 3.06–69.34, p < 0.01). Inconsistent condom use also significantly increased risk: “sometimes” use (OR = 21.47, 95% CI: 2.68-171.74, p < 0.01) and “never” use (OR = 47.82, 95% CI: 5.65-405.03, p < 0.01) compared to consistent use. Educational level and literacy were protective; women with secondary (OR = 0.21, 95% CI: 0.02–2.73) and tertiary education (OR = 0.20, 95% CI: 0.01–4.49) had lower odds of risky sexual behaviour. Women residing in densely populated settlements such as Kanyama, Mandevu, and Matero demonstrated higher sexual risk. Age, marital status, and religious affiliation showed trends but were not statistically significant in the adjusted model. Conclusion Risky sexual behaviour among women informal cross-border traders in Lusaka was largely driven by behavioural factors, particularly multiple sexual partnerships and inconsistent condom use, while education and literacy conferred protective effects. Interventions should prioritise sexual health education, condom negotiation skills, literacy programmes, and support for women in high-density settlements to reduce HIV vulnerability.