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

ObjectiveTo 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.DesignLaboratory study using human tissue.SettingUniversity-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/mm2) in peritoneal endometriotic lesions from hormone-treated women with endometriosis (10.6 ± 2.2/mm2) was statistically significantly lower than in peritoneal endometriotic lesions from untreated women with endometriosis (16.3 ±10.0/mm2). 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.