The impact of treatment on the natural history of endometriosis.

A group of 50 infertile female patients was assessed laparoscopically to study the natural history of endometriosis. They were treated either with danazol (n = 21), or diathermy ablation (n = 13) or had conservative surgery with postoperative danazol (n = 5) or were left untreated (n = 11). All these patients had second look laparoscopy performed after a mean interval of 12 months (range 9-18 months). Improvement was noted among 53% of those treated with danazol, 70% treated with diathermy, 80% treated with surgery and danazol and 27% of those left untreated. The status of endometriosis remained unchanged among 14% of those treated with danazol, 8% treated by diathermy and 9% of those left untreated. However, the disease became worse in the remaining women, 33% in the danazol treated group, 22% treated by diathermy, 20% treated with surgery and danazol and 64% of those left untreated. Thus treatment hinders progression in a majority of patients, and conversely, there is a small but definite spontaneous regression rate.