Follitropin-α (Gonal-F) versus follitropin-β (Puregon) in controlled ovarian hyperstimulation for in vitro fertilization : is there any difference?

In an attempt to examine and compare the effect of the two commercially available recombinant FSH on ovarian stimulation characteristics and IVF cycle outcome, we studied 264 IVF cycles in patients with a favorable prognosis a priori, 198 in patients using follitropin-α, and 68 in patients using follitropin-β. Although both groups achieved a comparable number of retrieved oocytes, the use of follitropin-β was associated with a tendency toward a lower clinical pregnancy rate (PR), and with significantly higher E 2 levels despite the use of significantly lower total gonadotropin dose.