Increasing the daily dose of recombinant follicle stimulating hormone (Puregon) does not compensate for the age-related decline in retrievable oocytes after ovarian stimulation.

A prospective, randomized, double-blind, multicentre (n = 6) study was conducted to compare the influence of either a 150 or 250 IU daily fixed-dose regimen of recombinant follicle stimulating hormone (FSH, Puregon) on the number of oocytes retrieved and the total dose used in down-regulated women between 30 and 39 years of age undergoing ovarian stimulation. In all, 138 women were treated with recombinant FSH, 67 with 150 IU and 71 with 250 IU. The number of oocytes retrieved in the low-dose group was 9.1 compared to 10.6 in the high-dose group (not significant). In the 30-33 years of age class receiving the 250 IU dose, a surplus of 4.2 oocytes (14.8 versus 10.6) was found, whereas in the 37-39 age class nearly one oocyte more was retrieved in the 150 IU group (8.1 versus 7.4). The total dose used to reach the criterion for human chorionic gonadotrophin (HCG) administration was 1727 IU for the women treated with 150 IU daily and 2701 IU for the 250 IU treated women (P < 0. 001). No significant relationships were found between serum FSH concentrations as obtained in the early follicular phase and the number of oocytes collected, or the total dose. It is concluded that in women between 30 and 39 years of age, the decline in number of oocytes retrieved with increasing age cannot be overcome by augmenting the daily dose of recombinant FSH from 150 to 250 IU.