Objective: To test the hypothesis that among women predicted to have a normal ovarian response, ovarian stimulation using 300 IU follicle-stimulating hormone (FSH) results in the retrieval of more mature oocytes than 225 IU during in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) treatment.
Design: Prospective randomised controlled study.
Setting: University-based assisted conception unit.
Population: A cohort of 131 women predicted to have a normal ovarian response to gonadotrophin stimulation, based on antral follicle count.
Methods: Subjects undergoing their first cycle of IVF/ICSI were randomised to receive a fixed daily dose of 300 (experimental arm) or 225 IU (control arm) of recombinant FSH (Gonal-F).
Main outcome measures: Number of mature oocytes retrieved and live birth rates.
Results: The number (mean +/- standard deviation) of mature oocytes retrieved (8.2 +/- 5.0 versus 9.0 +/- 4.8, for 300 and 225 IU, respectively; P = 0.34) was similar in each group. There were no differences between the 300- and 225 IU arms in live birth rates (31 versus 41%, respectively; P = 0.25), cycle cancellations resulting from insufficient ovarian response (0 versus 6.1%, respectively; P = 0.12), and prevalence of moderate (3.1 versus 3.0, respectively; P = 1.0) and severe (0 versus 1.5%, respectively; P = 1.0) ovarian hyperstimulation syndrome.
Conclusions: The use of a higher daily dose of 300 IU of recombinant FSH for ovarian stimulation does not improve the number of mature oocytes retrieved, or live birth rates, among women with a predicted normal response during conventional IVF/ICSI.