RECOMBINANT HUMAN FOLLICLE-STIMULATING-HORMONE (R-HFSH, GONAL-F(R)) VERSUS HIGHLY PURIFIED URINARY FSH (METRODIN HP(R)) - RESULTS OF A RANDOMIZED COMPARATIVE-STUDY IN WOMEN UNDERGOING ASSISTED REPRODUCTIVE TECHNIQUES

A prospective, randomized, comparative, assessor-blind study was carri ed out in two centres to compare the efficacy and safety of recombinan t human follicle stimulating hormone (r-hFSH; Gonal-F(R)) versus highl y purified urinary FSH (u-hFSH HP; Metrodin HP(R)), both administered s.c. in women undergoing ovarian stimulation for in-vitro fertilizatio n including intracytoplasmic sperm injection (ICSI). A total of 235 pa tients started a long gonadotrophin-releasing hormone agonist protocol : 119 received r-hFSH and 114 received u-hFSH HP (150 IU/day) for the first 6 days. Two patients were excluded from the study because they m istakenly received the incorrect treatment combination. Human chorioni c gonadotrophin (HCG; 10 000 IU, s.c.) was administered once there was at least one follicle 18 mm in diameter and two others greater than o r equal to 16 mm. In all, 119 (100%) and 102 (89%) of the patients res pectively in the r-hFSH and u-hFSH HP groups achieved the criteria for HCG. The mean numbers (+/- SD) of oocytes recovered (the primary endp oint) were 12.2 +/- 5.5 and 7.6 +/- 4.4 in the r-hFSH and u-hFSH HP gr oups respectively (P < 0.0001). However, the number of FSH treatment d ays (11.0 +/- 1.6 versus 13.5 +/- 3.7) and the number of 75 IU ampoule s (21.9 +/- 5.1 versus 31.9 +/- 13.4) used were significantly less (P < 0.0001) in the r-hFSH group than in the u-hFSH HP group. In patients treated using ICSI (63 patients in each group), no difference in oocy te maturation was observed. The mean numbers of embryos obtained were 8.1 +/- 4.2 and 4.7 +/- 3.5 (P < 0.0001), in favour of the r-hFSH grou p. In the majority of patients (96 and 99% respectively) only one or t wo embryos were replaced (mean 2.0 +/- 0.2 and 1.9 +/- 0.1 respectivel y) in the r-hFSH and u-hFSH HP groups. The clinical pregnancy rates pe r started cycle and per embryo transfer were 45 and 36%, and 48 and 47 %, respectively in the r-hFSH and u-hFSH HP groups (not significant). There were six (5.1%) and two (1.7%) cases of ovarian hyperstimulation syndrome respectively. In conclusion, it was found that r-hFSH was mo re effective than u-hFSH at inducing multiple follicular development. However, the high rate of low ovarian response in the u-hFSH group com pared with our general experience was unexpected. The availability of a gonadotrophin with less inter-batch variation would be beneficial fo r clinicians. r-hFSH seems to fulfil such a requirement.