Histologic analysis of specimens from laparoscopic endometrioma excision performed by different surgeons: does the surgeon matter? 
To evaluate whether the amount of ovarian tissue inadvertently removed along with the endometrioma cyst wall at laparoscopy differs in relation to the operating surgeon's level of expertise.  Multicenter, prospective trial.  Four tertiary care university hospitals.  Fifty patients, aged 25 to 40 years, with monolateral ovarian endometriomas who underwent laparoscopic excision.  Operation with the stripping technique by surgeons with specific expertise in endometriosis surgery in four centers (groups A, B, C, and D) and by residents with average training in laparoscopic surgery (group E).  Histologic examination for the evaluation of the mean thickness of the cyst wall from each specimen, and the mean thickness and morphologic characteristics of any ovarian tissue removed.  No statistically significant differences were present in the rate of presence of ovarian tissue in the endometrioma wall specimens from the different groups (44%, 45%, 55%, 56%, and 60% in groups A, B, C, D, and E, respectively).  For groups A+B+C+D versus group E, a statistically significant difference was found in the mean thickness of the tissue specimens (1.51 mm vs. 1.91 mm, respectively) and in the mean thickness of ovarian tissue inadvertently excised (0.49 mm vs. 0.97 mm, respectively).  Level of expertise in endometriosis surgery is inversely correlated with inadvertent removal of healthy ovarian tissue along with the endometrioma capsule.