BACKGROUND: In Norway, the guidelines for diagnostics and treatment of M. genitalium are unclear. The microbe is sexually transmitted, and causes urethritis, cervicitis, and possibly more serious complications as PID and infertility. In this project, I take a closer look at the prevalence in a STI-clinic, and see if there can be more clear recommendations. Olafiaklinikken offer home testing of M. genitalium and C. trachomatis. The test kit includes a urine sample for men, vaginal swab for women, and a sexual history form. This project combines the test results with various risk factors and symptoms reported in the form to check for significant associations. RESULTS: 3000 people were tested between February and October 2010, among these 1757 women and 1243 men. The prevalence was 4,8% for the women, and 4,7% for the men. 44% of the women and 46% of the men reported having some symptoms. Although the majority was asymptomatic, there was a significant association between infection and dysuria or discharge in the male population. There was also a significantly higher risk of positive test if the patient reported to have had M. genitalium previously. CONCLUSIONS: Based on the findings in this study and the increasing evidence of complications of M. genitalium, there should be more extensive testing. Tests shoud be performed at the same indications as C. trachomatis: after change of partner, in pregnancy and before abortions. Patients with symptoms of urethritis/cervicitis should also be tested. Five weeks after treatment, a control test should be performed, to exclude failure of treatment.