Objectives Recreational drug use has been found to be associated with high-risk sexual behaviour and with sexually transmitted infections (STI). This study is the first to assess the prevalence of drug use among swingers (heterosexuals who, as a couple, practise mate swapping or group sex, and/or visit sex clubs for couples), and its association with high-risk sexual behaviour and STI.

Methods We recruited individuals who self-identified as swingers and visited our STI clinic (from 2009 to 2012, South Limburg, The Netherlands). Participants (n=289; median age 45 years; 49% female) filled in a self-administered questionnaire on their sexual and drug use behaviour while swinging, over the preceding 6 months. We assessed associations between sexual behaviour, drug use and STI diagnoses (Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), syphilis, HIV and hepatitis B) using logistic regression analyses.

Results Overall, the prevalence of CT and/or NG was 13%. No other STIs were observed. Seventy-nine percent of swingers reported recreational drug use (including alcohol and use of erectile dysfunction drugs); 46% of them reported multiple drug use. Recreational drug use excluding alcohol and erectile dysfunction drugs (reported by 48%) was associated with high-risk behaviours in men and women. Drug use was independently associated with STI in female swingers, especially those who practice group sex.

Conclusions High rates of multiple drug use, as well as risky sexual behaviour and STIs among swingers, warrant paying more attention to this key population in prevention and care, as they are a risk group that is generally under-recognised and underserved in care.