Prolonged follicle stimulation decreases pregnancy rates after in vitro fertilization.
Ovarian stimulation with a GnRH-a and hMG for IVF treatment offers the potential to extend the period of follicle recruitment and growth free of the restriction imposed by a spontaneous midcycle LH surge. A randomized trial investigating the impact of extending follicle growth by 1 day resulted in a significantly reduced PR, despite an increase in the number of larger follicles (greater than or equal to 17 mm) at the time of hCG. The reason for a reduced PR was not related to the number of ova recovered or embryo quality. This suggests that follicular aging or the duration of estrogen rise may be important.
Clark
L
L
Lingard Fertility Centre, Newcastle, New South Wales, Australia.
Stanger
J
J
Brinsmead
M
M
D000328:Adult; D006063:Chorionic Gonadotropin / Q000008:administration & dosage / Q000627:therapeutic use*; D004624:Embryo Transfer; D004958:Estradiol / Q000097:blood; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood; D006080:Ovarian Follicle / Q000187:drug effects / Q000502:physiology*; D011247:Pregnancy; D011336:Probability; D011374:Progesterone / Q000097:blood
D006063:Chorionic Gonadotropin; D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone