Implications of using follicle-stimulating hormone preparations depleted of luteinizing hormone to achieve follicular growth in in vitro fertilization

Abstract

We aimed to compare the outcome of in vitro fertilization (IVF) treatment using follicle-stimulating hormone (FSH) containing gonadotropins with human menopausal gonadotropin (hMG) containing gonadotropins for ovarian stimulation. A retrospective analysis of 82 patients undergoing IVF in a private fertility clinic was performed over a specific period of time. Eighteen women received hMG, 20 received Normegon and 44 received FSH. In addition, 17 of these patients received hMG in one cycle and FSH in the other. The main outcome measures studied were duration of treatment, dose of gonadotropins required to achieve optimum follicular growth, number and size of follicles, endometrial thickness, serum estradiol concentrations, number of oocytes retrieved, pregnancy rates and the incidence of ovarian hyperstimulation syndrome (OHSS). At the time of administration of human chorionic gonadotropin (hCG), the mean (+/- SD) serum estradiol concentrations in patients treated with preparations containing FSH and luteinizing hormone (LH) in a ratio of 1:1 was 10,044.3 +/- 5378.8 pmol/l compared with 6819.5 +/- 2597.9 pmol/l in patients treated with preparations with FSH and LH in a ratio of 3:1 and 7369 +/- 4300 pmol/l in patients treated with FSH. The differences between the first and the second two groups were significant (p < 0.05). Endometrial thickness in the three groups of patients were 11 +/- 1.7 mm, 11 +/- 1.5 mm and 9.7 +/- 1.5 mm, respectively (p < 0.001). Comparing cycles of treatment with hMG and FSH in the same patient, we found significantly higher estradiol levels, thicker endometrium, more developing follicles and a shorter duration of treatment in the hMG-treated cycles compared with those in FSH-treated cycles. However, there were no differences between the incidence of OHSS or the pregnancy rates between the three treatment groups. With the advent of recombinant human FSH and the shortage of LH-containing preparations, it is important to note that serum estradiol concentrations on the day of administration of hCG underrepresent the degree of follicular maturation. In the context of the use of a 'long' protocol of gonadotropin-releasing hormone (GnRH) analog therapy and LH-depleted gonadotropin preparations, serum estradiol is no longer a reliable marker of follicle development.