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 a n attractive alternative to urinary FSH (uFSH) for ovarian stimulation. Sev eral trials have compared the two preparations, but none had sufficient pow er to detect a clinically meaningful difference in pregnancy rates. The pur pose of this study was to determine the clinical pregnancy rates per starte d cycle by pooling data from randomized trials which compared the use of rF SH and uFSH in treatment cycles using in-vitro fertilization (IVF) or intra cytoplasmic sperm injection (ICSI), A thorough search of the literature ide ntified 12 trials which met the inclusion criteria. In four trials, both IV F and ICSI were performed, in seven trials only IVF was performed and in on e trial only ICSI was performed. Data were extracted and pooled using the p rinciples of meta-analysis. There was no significant heterogeneity of treat ment effect across the trials. The common odds ratio and the risk differenc e (and their 95 % confidence intervals), obtained by pooling the data using a fixed effects model, were 1.20 (1.02-1.42) and 3.7% (0.5-6.9%) respectiv ely, in favour of rFSH, The pregnancy rate with the alpha preparation of rF SH was statistically significantly higher than with uFSH in IVF cycles, The overall conclusion from this meta-analysis is that the use of rFSH in assi sted reproduction is preferred over uFSH.