Recombinant Follicular Stimulating Hormone Plus Recombinant Luteinizing Hormone versus Human Menopausal Gonadotropins - Does the Source of LH Bioactivity Affect Ovarian Stimulation Outcome?

Michal Kirshenbaum Or Gil Jigal Haas Ravit Nahum Eran Zilberberg Oshrit Lebovitz Raoul Orvieto
Obstetrics and Gynecology, Sheba Medical Center, Israel

Introduction:
LH and hCG activate different intracellular signalling cascades. However, due to similar structure and common receptor, they are used interchangeably during ovarian stimulation (OS).

Aims:
To study if the source of luteinizing hormone (LH) used during OS affect IVF outcome.

Methods:
Cross sectional study of all patients who underwent two consecutive IVF cycles, one included r-LH (Pergoveris) and the other included urinary hCG [highly purified hMG (HP-hMG), (Menopur)]. The OS protocol, except of the LH preparation, was identical in the two IVF cycles. Primary outcome was the rate of mature oocytes retrieved. Secondary outcomes were the number of matured and fertilized oocytes, number of top-quality embryos and pregnancy rate.

Results:
The rate of mature oocytes was not different between the treatment cycles (0.9 in the rFSH+rLH vs 0.8 in the HP-hMH, p=0.07). Nonetheless, the mean number of mature oocytes retrieved in the rFSH+rLH treatment cycles was higher compared to the HP-hMG treatment cycles (10 ± 5.8 vs 8.3 ±4.6, respectively, P=0.01). Likewise, the mean number of fertilized oocytes was higher in the rFSH+rLH cycles compared with the HP-hMG cycles (8.5 ± 5.9 vs 6.4 ± 3.6, respectively, p=0.05). There was no difference between the treatments regarding the number of top-quality embryos, ratio of top-quality embryos per number of oocytes retrieved or fertilized oocytes or pregnancy rate.

Conclusions:
The differences in treatment outcome, derived by different LH preparations reflect the distinct physiological role of these molecules. Our findings may assist in tailoring a specific GT regimen when assembling an OS protocol.