OBJECTIVE: Our purpose was to assess the efficacy of two recombinant follicle-stimulating hormones, follitropin beta (Follistim, Organon, West Orange, NJ) and follitropin alfa (Gonal F, Serono, Norwell, Mass) on pregnancy rates in varying age groups of women undergoing in vitro fertilization (IVF).

STUDY DESIGN: Three hundred sixty-five IVF cycles were retrospectively compared, 233 by use of follitropin beta and 132 by use of follitropin alfa, both after gonadotropin-releasing hormone agonist down-regulation. Assignment to each medication was indiscriminate. The primary outcome measured was pregnancy evidenced by fetal heartbeat on ultrasonography. Secondary outcomes included days of stimulation, ampules per patient cycle, estradiol level on the day of human chorionic gonadotropin administration, total follicles present on the day of human chorionic gonadotropin administration, follicles greater than 14 mm, oocytes retrieved, mature eggs, fertilization rate, and embryos transferred. Outcomes were stratified by age, including women less than 36 years old, 36 to 39 years old, and more than 39 years old.

RESULTS: There was no significant difference between follitropin beta and follitropin alfa in either the primary or secondary outcomes, although the pregnancy rate was significantly decreased with advancing age.

CONCLUSION: Success rates are similar, when stratified by age, in women undergoing IVF with either follitropin beta or follitropin alfa.