Recombinant versus urinary follicle stimulating hormone for ovarian stimulation in assisted reproduction

The recent availability of recombinant follicle stimulating hormone (rFSH), with its high level of purity and batch-to-batch consistency has made it an attractive alternative to urinary FSH (uFSH) for ovarian stimulation. Several trials have compared the two preparations, but none had sufficient power to detect a clinically meaningful difference in pregnancy rates. The purpose of this study was to determine the clinical pregnancy rates per …