Differences in serum LH and FSH levels using depot or daily GnRH agonists in controlled ovarian stimulation: influence on ovarian response and outcome of ART

Purpose: To study effects of endogenous LH levels on ovarian response and outcome in ART cycles a controlled study was performed with two patient groups differing in the intensity of pituitary downregulation. Methods: Group I (n = 27) received 3.75 mg of the GnRH agonist triptorelin acetate depot, group II (n = 54) was given 0.1 mg triptorelin acetate daily, followed by ovarian stimulation with recombinant FSH. Results: After downregulation serum LH and FSH levels were significantly lower in group I. Patients of group I needed significantly higher FSH doses to achieve comparable levels of serum estradiol and preovulatory follicles. The number of retrieved oocytes and transferable embryos was lower in group I. Conclusion: Patients with profound endogenous LH suppression by depot GnRH agonists show higher FSH stimulation dose requirements and lower oocyte number and fertilization rate, indicating a need for minimal LH activity in folliculogenesis and oocyte development.