There are various theories on the best administration schedules among users in bodybuilding. It’s far more simple in fertility therapy in women and for endocrinology related disorders in men.
For women: fertility is exclusive to the ovulation phase and short durations pre and post if viable sperm is still around. However, the public health message that “pull out” is ineffective for birth control is scientific nonsense, with pregnancy possible only during ovulation AND if there are viable sperm in the male urethra before sex (peeing clears them out, and there’s so few leftover from ejaculation anyway). The troubling truth is that women often have difficulty with becoming pregnant - even during ovulation. HCG is administered to induce or prolong ovulation in these women, and in so doing there are more chances for successful pregnancies.
For Men: If you’re testes are “shut down” from disease or steroid abuse, HCG is a miraculous treatment. Some users take small amounts throughout their cycle. Others, like myself, prefer an aggressive PCT protocol; I like to take high dose HCG (and Clomid or Tamoxifen) multiple times in the week or two following steroid cessation and biological elimination of exogenous hormones.
The luteinizing hormone in males is part of the hypothalamus-pituitary axis, and when the body’s testosterone is production functioning correctly, it is responsible for 95% of male testosterone production from its work in the leydig cells in the testicles. It’s partner, follicle stimulating hormone, responsible for spermatogenesis in the sertoli cells. Once testosterone is reduced, LH, FSH, and free the leydig cell testosterone levels are signals to the hypothalamus to release, we think, GHrH or other messengers that travel from the hypothalamus to the anterior pituitary where LH and FSH are once again released and bound for the testes. Taking HCG is effectively taking LH for both men and women. It’s biological effects mimic LH so well that, in males, LH (and to some degree FSH) are kickstarted to resume the normal testosterone hypothalamus-pituitary axis. Clomid may do the same thing but requires at least a month (-according to my endocrinologist) and HCG is taken in easy subcutaneous injections every couple days for a week. Get labs and if FSH and LH aren’t rising much, continue HCG and add clomid or tamoxifen. Short, aggressive durations are best in my opinion because they’re new substances in the body and no sensitization effects are risked.
lastly, HCG may make you feel a slight bit happier, and helps a tiny bit with cellular apoptosis so helpful in cancer.