Effect of a partially desialylated human chorionic gonadotropin preparation (Desialo hCG) on ovarian function

Six patients with unexplained infertility were administered a partially desialylated hCG preparation (Desialo hCG). 5000 and 10000 IU of this preparation were given as a single IM dose, following the administration of hMG-Pergonal. The circulatory half-life (t 1/2) of Desialo hCG was found to be 42.6 hours, which is similar to the t 1/2 of 35.6 hours previously reported for a hybrid hCG preparation. The t 1/2 values were shorter than the t 1/2 of 65.3 hours estimated for commercial hCG administered by the same route. In spite of the similarities in t 1/2 values between the two preparations, serum progesterone levels were significantly increased 48 to 96 hours after the administration of Desialo hCG, and only 8 to 10 hours after the administration of the hCG hybrid. The difference in response may reflect differences in receptor occupancy at the ovarian level. Large scale testing of preparations with half-lives approaching the t 1/2 of the physiological hormone, hLH, should be carried out in order to determine if the risk of overstimulation and/or multiple pregnancies could be reduced thus, allowing for a safer therapeutic modality in patients pre-treated with hMG.