Highly purified FSH is as efficacious as recombinant FSH for ovulation induction in women with WHO Group II anovulatory infertility: a randomized controlled non-inferiority trial

BACKGROUND The objective of this study was to demonstrate non-inferiority of a highly purified urinary follicle stimulating hormone (HP-FSH) preparation compared with a recombinant (rFSH) preparation with respect to ovulation rate (primary end-point). METHODS This was a randomized, open-label, assessor-blind, multinational study. Women with anovulatory infertility WHO Group II and resistant to clomiphene citrate were randomized (computer-generated list) to stimulation with HP-FSH (n = 73) or rFSH (n = 78) using a low-dose step-up protocol. The non-inferiority limit was prespecified at -20%. RESULTS The ovulation rate was 85.2% (51/62) with HP-FSH and 90.9% (60/66) with rFSH (per-protocol population), and non-inferiority was demonstrated [95% confidence interval: -16.9; 5.6]. No differences were noted between groups in number of follicles >/=12 mm, >/=15 mm or >/= 18 mm, mono-follicular development, pregnancy rates, endometrial thickness, number of ovarian stimulation syndrome cases or frequency of injection site reactions/pain. The singleton live birth rate was 15% in both groups (11/73 with HP-FSH and 12/78 with rFSH). CONCLUSIONS This urinary HP-FSH preparation is non-inferior compared with a rFSH preparation with respect to ovulation rate in anovulatory WHO Group II women failing to ovulate or conceive on clomiphene citrate.