recombinant human chorionic gonadotrophin + letrozole

This investigational androgen priming protocol was developed by Mỹ Đức Hospital in Ho Chi Minh City, Vietnam, specifically for women with poor ovarian response (POR) who meet the Bologna criteria. The regimen consists of a combination of low-dose recombinant human chorionic gonadotrophin (rHCG) and the aromatase inhibitor letrozole, administered for eight weeks prior to ovarian stimulation. The biological mechanism is designed to induce intra-ovarian androgenization: rHCG stimulates the production of endogenous androgens in the theca cells, while letrozole prevents their conversion into estrogens by inhibiting the aromatase enzyme. This elevated androgen environment is hypothesized to enhance the recruitment and growth of the residual follicular pool. A pilot study (NCT03447184) conducted at IVFMD, Mỹ Đức Hospital, evaluated this long-term priming regimen but found no significant effect on hormone levels, antral follicle count, or the number of recruitable follicles in the target patient population.

Other names

Androgen primingAndrogen priming protocolLong-term endogenous androgen priming