Effect of danazol on the pregnancy rate in patients with unsuccessful in vitro fertilization-embryo transfer

OBJECTIVE: To determine the effect of danazol on in vitro fertilization- embryo transfer (IVF-ET) patients who failed to conceive in previous attempts despite having embryos with optimal morphology, whether endometriosis is present or not. STUDY DESIGN: In this prospective, randomized, controlled study, of 81 patients who experienced unexplained failures of IVF-ET despite having goodmorphology embryos, 40 received danazol (400 mg/d orally for 12 weeks) following the unsuccessful IVF-ET cycle. The next IVF-ET was performed within three months of the first spontaneous ovulation after danazol administration. The remaining 41 patients constituted the control group, and in them the next IVF-ET was performed within six months after the previous failed cycle. RESULTS: Conception occurred in 16 of 40 (40%) danazol-treated patients at the subsequent cycle and showed a significant increase when compared with 8 of 41 (19.5%) control subjects (P < .05), though the number of embryos with optimal morphology decreased after danazol treatment. CONCLUSION: Danazol may be used for patients who have had repeated failures of IVF-ET despite having morphologically optimal embryos and may be useful for increasing receptivity of the endometrium in these patients.