Also, nosignificant difference was found in women with severe endometriosis.17 Two observational studies of women with endometriomaresection13,15 reported no significant difference in FR althoughthe RCT found a significantly higher FR when the long GnRH-agonist was usedin resected endometrioma (p = 0.001) but not in active endometrioma.19 This evidence concerns the gene GNRH1 and endometriosis.