Edinburgh Napier University

  Background
Chlamydia trachomatis (C. trachomatis) is the most common bacterial sexually transmitted infection in the UK. Recent studies suggest that in addition to the genital tract, C. trachomatis is found in the throat and rectum, suggesting the number of infections is under-reported. There is an urgent need to study the impact of extending diagnosis to include extra-genital samples; however, there is a lack of evidence on the acceptability of asking young women to provide these samples.

Method
A mixed methods single group feasibility study explored the acceptability of combined genital and extra-genital testing in young women aged 16–25 years consecutively attending a sexual health centre in Edinburgh, Scotland. Young women were asked to complete a self- administered anonymous questionnaire whether they would be willing to give self-taken throat and ano-rectal samples. Interviews with women (n = 20) willing to self-sample were conducted before and after self-sampling, and these explored the underlying reasons behind their decision, and feelings about the tests.

Results
Of 500 women recruited to the study, 422 (84.4%) women provided sufficient data for analysis. From completed questionnaires, 86.3% of respondents reported willingness to self-sample from the throat. Willingness of ano-rectal self-sampling was lower (59.1%), particularly in women under 20 ( < 20 years: 44.4%; ≥20 years, 68.2%). Willingness of ano-rectal self-sampling was higher in women who had more sexual partners in the last 6 months (0 partners, 48.3%, n = 14, 3 or more partners, 67.4%, n = 60) and in those who have previous experience of a positive test for a sexually transmitted infection (STI) (positive: 64.5%; negative: 57%). Interviewed women suggested that a lack of knowledge of STIs, embarrassment and lack of confidence in the ability to carry out the sampling were barriers towards acceptability.

Conclusions
In this study, self-sampling of throat samples is largely acceptable; however, the acceptability of taking an ano-rectal sample for C. trachomatis testing in young women was lower in younger women. The study suggests further research to investigate the acceptability of extra-genital testing as an addition to routine C. trachomatis testing, and whether this increases detection and prevents infective sequelae for women.