Cumulative risk and graded associations with high-risk sexual behaviors among Chinese university students: a cross-sectional study

Chinese university students experience sexual maturation and psychosexual development, which may be associated with an increased likelihood of high-risk sexual behaviors (HRSB). This study aimed to estimate the prevalence of HRSB among Chinese university students and quantify the cumulative effects of multiple risk factors on HRSB. This cross-sectional survey employed stratified cluster sampling and was conducted among 2,722 students from four universities in Luzhou City, Sichuan Province, China. Data on demographics, sexual knowledge, attitudes, and experiences were collected via a self-administered questionnaire. Multivariable logistic regression was performed to identify factors associated with HRSB, and the cumulative effect of risk factors was examined by categorizing participants according to the number of accumulated risk factors, with a test for linear trend to evaluate the graded association. Overall, 325 students (11.94%, 95% CI : 10.72–13.16) reported HRSB. Male sex (a OR = 2.75, 95% CI : 2.05–3.69), grade ≥ 4 (a OR = 1.84, 95% CI : 1.35–2.51), non-medical major (a OR = 1.96, 95% CI : 1.41–2.72), same-sex sexual experience (a OR = 4.00, 95% CI : 2.63–6.10), permissive attitude toward premarital sex (a OR = 2.63, 95% CI : 2.01–3.43), other-relatives caregiver before age 18 (a OR = 2.75, 95% CI : 1.58–4.77), childhood sexual abuse (a OR = 2.64, 95% CI : 1.85–3.76), and adequate sexual knowledge (a OR = 1.94, 95% CI : 1.36–2.76) were independently associated with HRSB. A total of 33.72% of students had two or more cumulative risk factors. A clear graded association was observed between the number of accumulated risk factors and HRSB. Compared to students with zero risk factors, those with one factor had non-significantly increased odds (a OR = 1.63, 95% CI : 0.98–2.72), whereas those with two factors had 5.01-fold higher odds (a OR = 5.01, 95% CI : 3.01–8.53), and those with three or more factors had 15.66-fold higher odds (a OR = 15.66, 95% CI : 8.69–28.21). Approximately one in eight university students reported HRSB, with risk escalating progressively as risk factors accumulated. One-third of students had multiple cumulative risks, and those with three or more factors had nearly 16-fold higher odds of HRSB compared to those with none. These findings underscore the urgent need for comprehensive, evidence-based sexual health programs that simultaneously address cumulative risk profiles in this population.