105 adolescent girls with mean age of 17.3 (11-19) years had laparoscopy/pelviscopy between 1996 and 1997. In 37 cases, endometriosis was diagnosed (35.2%). The majority of the girls (32.4%) presented with endoscopic endometriosis classification (EEC) stage I. 2.8% of the girls had stage EEC II. The lesions involved one site or pelvic organ (64.8%) with a mean age of 18.7 (14-19) years. In 35.2% of cases, the lesions were at multiple sites with a mean age of 16.9 (11-19) years. Indications for laparoscopy included chronic or acute pelvic pain and right-sided lower abdominal pain. Endometriotic lesions were found in the pouch of Douglas (64.8%), uterosacral ligaments (37.8%), and ovarian fossa (24.3%), 42.8% of directed biopsies were positive. Endocoagulation of the endometriotic lesions was performed in 91.9% of cases.