Letrozole Alone Protocol Versus Using Letrozole and HCG Protocol

Letrozole is a chemical compound, CGS 20267 which is a third-generation, nonsteroidal aromatase inhibitor. Letrozole blocks estrogen synthesis by directly affecting the hypothalamic-pituitary-ovarian axis, subsequently, increases gonadotropins which increase pregnancy rates. Possible positive outcomes of aromatase inhibitors over selective estrogen-receptor modulators include a more physiologic hormonal stimulation of the endometrium which increases receptivity, a lower multiple-pregnancy through single follicle growth, a lesser side-effect especially vasomotor and mood symptoms, and more prompt clearance from blood, hence, reducing the probabilities of periconceptional exposure