Is danazol safe for women who are pregnant or breastfeeding?

No. Danocrine (danazol) is a potent male-hormone like drug. There is no place for treatment with Danocrine (danazol) in a pregnant or breast-feeding woman!
No. Danazol can cause a number of problems in pregnancy including problems with the genitalia. We don't recommend it during these problems. Fortunately, Danazol is used for endometriosis which is usually improved in pregnancy.