Maximal plasma HCG - human chorionic gonadotropin - levels will be reached in males approximately 6 and 16 hours after a single intramuscular or subcutaneous injection of hCG, respectively and in females after approximately 20 hours. HCG is approximately 80 per cent metabolized, predominantly in the kidneys. Intramuscular and subcutaneous administration of hCG were found to be bioequivalent regarding the extent of absorption and the apparent elimination half-lives of approximately 33 hours. On basis of the recommended dose regimens and elimination half-life, cumulation is not expected to occur.