Background Child sexual exploitation (CSE) is a challenging diagnosis to make, with few clinical signs or symptoms, and little evidence that markers such as sexually transmitted infections (STIs) are CSE predictors.

Aim To investigate associations between STIs and CSE risk factors.

Methods The genitourinary medicine clinic activity dataset (GUMCAD) was used to identify clinics with >18 STI diagnoses in 13–15 year-olds in 2012. Cases with confirmed bacterial or protozoal STIs were matched by age, gender and clinic with non-STI controls. Clinics provided details of CSE-related risk factors irrespective of STI presence through an on-line questionnaire. Associations between STI outcome and CSE-related risk factors were analysed using logistic regression.

Results 18/44 (40.9%) clinics contacted provided data on 466 13–15 year-olds; 414 (88.8%) were female, and 52 (11.2%) male. 98.6% were heterosexual, and 66.7% white British. There were 18 (3.9%) 13, 108 (23.2%) 14 and 340 (80.0%) 15 year-olds. In univariate analysis an STI diagnosis was significantly associated with: ‘highly-likely’ CSE (OR 9.00, p = 0.037), >1 partner (OR 5.50, p = 0.000), >1 attendance in 2012 (OR 3.79, p = 0.0000), safeguarding referral (OR 1.94, p = 0.022), other service involvement (OR 1.72, p = 0.031) and vulnerability (OR 1.64, p = 0.026). After adjustment, STI diagnosis was significantly associated with: Health Advisor review (OR 6.78, p = 0.000), >1 partner (OR 5.82, p = 0.002), >1 attendance (OR 3.72, p = 0.000) and looked after child (OR 3.43, p = 0.039).

Discussion The presence of a bacterial or protozoal STI is only weakly associated with CSE and should not be used to infer CSE in the absence of more compelling evidence.