letrozole + GnRH antagonist

This combination therapy regimen is being investigated by Cairo University researchers for the treatment of infertility in women classified as poor ovarian responders undergoing in vitro fertilization and embryo transfer (IVF-ET). The protocol utilizes letrozole, an aromatase inhibitor, as an adjuvant to a gonadotropin-releasing hormone (GnRH) antagonist protocol. Letrozole works by blocking the conversion of androgens to estrogens, which reduces negative feedback on the hypothalamus and pituitary, thereby increasing endogenous follicle-stimulating hormone (FSH) secretion and potentially enhancing ovarian sensitivity to exogenous gonadotropins. The GnRH antagonist (specifically cetrorelix) is used to prevent premature luteinizing hormone (LH) surges and ovulation. The Cairo University study specifically compares extended high-dose versus short low-dose letrozole administration alongside highly purified urinary FSH (HP-uFSH) to optimize oocyte yield and pregnancy outcomes in this difficult-to-treat patient population.

Brand names

Fostimon

Other names

letrozole + cetrorelixletrozole + HP-uFSH + GnRH antagonist protocol