The effect of gonadotrophin-releasing hormone (GnRH) agonist in the follicular phase on in-vitro fertilization outcome in normo-ovulatory women.

Sixty-three normo-ovulatory infertile women were randomly divided into two groups. All women were first desensitized with the gonadotrophin-releasing hormone agonist (GnRHa), buserelin. Thereafter, ovarian stimulation with human menopausal gonadotrophins (HMG) was started in both groups but in group A the GnRHa was stopped on the same day. In group B, the GnRHa was continued during HMG treatment until the ovulatory human chorionic gonadotrophin stimulus was given. Premature luteinization was not observed in either group, although the preovulatory basal luteinizing hormone (LH) secretion was significantly higher in group A. An equal number of embryos of comparable quality was transferred in both groups and the pregnancy outcome was similar. However, the supernumerary embryos of group A were of a lower morphological quality and survived the cryopreservation process less well. We concluded that the continuous administration of a GnRH agonist during HMG treatment resulted in better quality of supernumerary embryos.