text: Human chorionic gonadotropin injection is extensively used for final maturation induction in lieu of luteinizing hormone. In the presence of one or more mature ovarian follicles, ovulation can be triggered by the administration of HCG. As ovulation will happen between 38 and 40 hours after a single HCG injection, procedures can be scheduled to take advantage of this time sequence, such as intrauterine insemination or sexual intercourse. Also, patients that undergo IVF, in general, receive HCG to trigger the ovulation process, but have an oocyte retrieval performed at about 34 to 36 hours after injection, a few hours before the eggs actually would be released from the ovary.
  As hCG supports the corpus luteum, administration of HCG is used in certain circumstances to enhance the production of progesterone.
  In the male, hCG injections are used to stimulate the Leydig cells to synthesize testosterone. The intratesticular testosterone is necessary for spermatogenesis from the sertoli cells. Typical uses for hCG in men include hypogonadism and fertility treatment, including during testosterone replacement therapy to restore or maintain fertility and prevent testicular atrophy.
  Several vaccines against human chorionic gonadotropin (hCG) for the prevention of pregnancy are currently in clinical trials.