Online sex-seeking among Chinese heterosexual men who seek care in sexually transmitted infections clinics: a cross-sectional study

BACKGROUND: The Internet has become an important virtual venue for men who have sex with men to seek sexual partners, with a high potential threat to spread sexually transmitted infections (STIs). However, the online sex-seeking use and its risk causing STIs spread remain unclear among heterosexual men. We conducted a cross-sectional study to investigate the use of online sex-seeking venues and the related risky sex activities (e.g. condomless sex, quick sex) in STIs clinics in Guangdong, China. METHODS: These STIs clinics were involved in the Guangdong governmental sentinel network and we recruited heterosexual men (age > = 18) between March and August 2018. Multivariable logistic regression models were used to identify the factors associated with online sex-seeking use and risky sex activities with online sex partners. RESULTS: 191 of 2,154 participants (8.9%) ever sought sex online. Among users,16.8% met their partners in-person within 24 h, 31.4% engaged in condomless sex with their last online partner. Online sex-seeking was positively associated with a) Ever been diagnosed with STIs (aOR = 3.0, 95%CI:2.0–4.6), and b) Had casual sex in the last three months (aOR = 3.3, 95%CI 2.4–4.6). Condomless sex with the last online partner was negatively associated with the correct answer of “Having only one partner can reduce the risk to infect HIV” (aOR = 0.3, 95%CI:0.1–0.8). CONCLUSION: In China, online sex-seeking and its related risky sexual activities are not rare among heterosexual men. Future prevention strategies to reduce STIs incidence should especially target heterosexual men engaging in online sex-seeking. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13690-022-00903-5.