Objectives The objective was to describe the prevalence of sexually transmitted infections (STI) and blood-borne viruses (BBV), and prophylactic treatment offered to female postpubertal patients attending a Norwegian Sexual Assault Centre (SAC). We wanted to evaluate whether STIs diagnosed at the initial visit could have been assault-transmitted, and to explore whether background and assault characteristics were associated with diagnosed STI/BBV.

Methods We included postpubertal females ≥12 years of age attending the SAC within 1 week of the assault. Data were collected from records. We conducted a retrospective, descriptive study, and used logistic regression analysis.

Results Among 412 patients with a median age of 21 years, 35 patients had an STI (8.5%), two of which probably were assault-transmitted. Chlamydia trachomatis was the dominating agent, detected in 25 patients (6.4%). At serology screening, 3.7% tested positive for hepatitis C and/or hepatitis B core antibody. Patient age 16–19 years was associated with STI, while BBV positives were older. Non-Western assailant was associated with STI, while substance abuse was associated with STI and BBV. In order to prevent potential transmission of STI not identified at the initial visit, 91% accepted prophylaxis against bacterial STI, while antiviral prophylaxis was offered to less than one-fifth of the patients.

Conclusions The C trachomatis prevalence among the sexual assault patients was lower than in a comparable clinical population. The STI was suspected to be assault-transmitted in only two cases.