Inadequate access to prevention and medical treatment for female sex workers (SW) represents a challenge for the German health system. Accessibility and care for SW in Bochum (Germany) through a cooperation between the Interdisciplinary Immunology Outpatient Clinic, Center for Sexual Health and Medicine of St. Josef's Hospital, the Bochum health department and the Madonna e.V. was the focus of this work. Medical outreach services were provided for the diagnosis of sexually transmitted infections (STI) in SW in brothels in Bochum between August 2013 and January 2014. After clarification and verbal consent from the SW, free HIV, syphilis, chlamydia, gonorrhea and trichomoniasis tests were offered and carried out using pseudonyms for the SW. A total of 112 SW were reached (up to 55.4 % within the framework of the STI Outreach Study). Of the SW, 94.6 % had an immigrant background. The majority (61.3 %) of SW were between 20 und 29 years old. Only 19.0 % of the collective had health insurance. The following STIs were diagnosed: 12.5 % chlamydia, 6.2 % syphilis, 3.6 % gonorrhea, 3.6 % trichomoniasis, and 0.9 % HIV. These results were compared with results from STI studies in SW in Germany. Treatment was performed in accordance with the standards of the German STI Society. The offer improved the accessibility and the utilization of medical services by SW in Bochum. A further improvement of services is urgently needed.