Endometriosis is an important cause of pelvic pain in adolescence.

OBJECTIVE despite endometriosis being a common disease, where early detection is key to preventing its progression, it is a condition often overlooked in adolescents. The aim of this study was to report the clinical characteristics of adolescent patients with endometriosis monitored in a tertiary hospital. METHODS a retrospective study of 394 patients undergoing surgery with a histological diagnosis of endometriosis at the Endometriosis Division of the Gynecology Department at the Hospital das Clínicas of the University of São Paulo Medical School from 2008 to 2013. 21 adolescents were included (aged under 21 years). RESULTS the age ranged from 17.95 ± 1.48 years, the average time for diagnostic confirmation was 2.96 ± 2.93 years, and the age at the onset of symptoms was 15.28 ± 3.03 years on average. The sites affected were ovarian (38%), peritoneal (47.6%) and retrocervical (23.8%). Dysmenorrhea was found in 80.9 % of adolescents (severe in 33.3% of cases) and chronic pelvic pain in 66.6%. CONCLUSION endometriosis in adolescents is an important differential diagnosis from pelvic pain and ovarian cysts, mainly among those with no response to conventional treatment. The main forms of involvement are peritoneal and ovarian. Despite the onset of symptoms in adolescence and advances in imaging methods, the diagnosis of this disease is still delayed.