Effect of progestogens and combined oral contraceptives on nerve fibers in peritoneal endometriosis

Objective: To investigate how progestogens and combined oral contraceptives change nerve fiber density in peritoneal endometriotic lesions and to identify the types of nerve fibers still present during hormone treatment. Design: Laboratory study using human tissue. Setting: University-based laboratory. Patient(s): Hormonally treated and untreated women with endometriosis undergoing laparoscopy, hysteroscopy, and curettage. Intervention(s): Biopsy samples from peritoneal endometriotic lesions in hormonally treated and untreated women with endometriosis. Main Outcome Measure(s): Types and density of nerve fibers were immunohistochemically determined in peritoneal endometriotic lesions from hormonally treated and untreated women with endometriosis. Result(s): The nerve fiber density (mean +/- standard deviation/mm(2)) in peritoneal endometriotic lesions from hormone-treated women with endometriosis (10.6 +/- 2.2/mm(2)) was statistically significantly lower than in peritoneal endometriotic lesions from untreated women with endometriosis (16.3 +/- 10.0/mm(2)). Nerve growth factor and nerve growth factor receptor p75 expression in peritoneal endometriotic lesions were slightly reduced in hormone-treated women with endometriosis compared with untreated women with endometriosis. Conclusion(s): Progestogens and combined oral contraceptives reduced nerve fiber density and nerve growth factor and nerve growth factor receptor p75 expression in peritoneal endometriotic lesions. (Fertil Steril (R) 2009; 92:1234-9. (C) 2009 by American Society for Reproductive Medicine.)