RESUMEN
OBJECTIVE: Several strategies have been proposed for ovarian stimulation in older women, such as using an increased daily dose of gonadotropins (300-450 IU per day) with GnRH agonist (long or micro dose flare protocols), or using GnRH antagonist protocols. The objective of this study is to compare the efficacy of flexible GnRH antagonist protocol and GnRH agonist flare - pituitary block protocols for ovarian stimulation in women above 40 years old undergoing IVF. METHODS: This study was performed between January 2016 and February 2019. One hundred and fourteen women aged between 40 and 42 years who underwent IVF were divided into two groups; group I were treated by Flexible GnRH antagonist protocol (Antagonist group, n=68); and group II were treated by Flare GnRH agonist protocol (Flare group, n=46). RESULTS: Patients treated with the antagonist protocol had a significantly lower cancellation rate when compared with patients treated with flare agonist protocol (10.3% vs. 21.7%, p value 0.049). The other parameters evaluated did not show statistically significant differences. CONCLUSIONS: Our finding showed that both Flexible antagonist and Flare agonist protocols had comparable outcomes, with lower cycle cancellation rates for older patients treated with the antagonist protocol.