HCG
The shot that keeps your testes working and your fertility intact while you are on testosterone. A real medicine, dosed to your bloodwork.
What it is
If you are on TRT and want to keep your testicles their normal size, keep making sperm, and avoid the flat libido that comes when they shut down, hCG is what does that. It stands in for the brain signal that testosterone therapy switches off.
Three groups use it. Men on TRT who want to stay fertile or just do not want shrunken, aching testicles and the libido dip that comes with them. Men coming off testosterone or a cycle, to restart their own production. And men with low testosterone who would rather raise their own than inject the hormone itself, which also keeps fertility, and is how a lot of urologists treat younger men. It is an approved prescription medicine, originally for fertility, and most TRT clinics will prescribe it alongside testosterone.
On TRT, the first thing people notice is testicular fullness coming back inside two to three weeks, then libido and the quality of erections, and often mood and energy, since intratesticular testosterone and the small amount of estrogen it makes matter more than people expect. For fertility, nothing is quick: sperm take about three months to mature, so a semen test before month three tells you little. For a restart, expect a few weeks before your own levels respond.
The standard TRT dose is 250 IU three times a week, subQ with an insulin syringe, anywhere on the belly; some go 500 IU twice a week. Fertility doses run higher, up to 2000 IU, and those are set by a doctor against labs. The mistake that bites most people is too much: hCG raises estradiol as well as testosterone, because the testes turn some of the extra testosterone into it, and 500 IU or more every other day on top of TRT gives you water retention, moody weeks and tender nipples. Keep an eye on estradiol for as long as you run it. The other mistake is treating it as optional and only starting after months of shrinkage. A 5000 IU vial is 20 doses at 250 IU, about six to seven weeks, which fits inside the 60 days the Pregnyl label allows once mixed and refrigerated; it is fragile, so swirl, never shake.
The evidence is as strong as it gets here: decades of human use, FDA approval for fertility and hypogonadism, and good data that it maintains sperm production and testicular volume on TRT. The one thing it is famous for that does not work is the 'hCG diet'. Controlled trials found the weight loss came from the 500-calorie diet, not the shots, and the FDA has said so plainly.
Not worth it if you are not on testosterone and have no fertility goal; it does nothing useful on its own for a man with normal levels. If you cannot get it prescribed, gonadorelin is the common clinic substitute, though it is weaker and needs more frequent dosing. For fertility specifically, HMG is sometimes added when hCG alone is not enough. Women use hCG in fertility treatment too, but that is a clinic protocol, not something this page covers.
What people use it for
Staying fertile on testosterone
Most evidenceTestosterone shuts down sperm production in most men within months. Studies of men on TRT who added low-dose hCG kept normal sperm counts and intratesticular testosterone, and men who stopped and restarted recovered. This is the main clinical reason it exists in a TRT protocol.
Fertility treatment
Most evidenceIts original approved use. In men with low gonadotropins it restores sperm production, often alongside FSH or HMG, with decades of clinical data. In women it triggers ovulation in IVF cycles. These are supervised, lab-guided protocols.
Testicular size, libido and mood on TRT
Some evidenceMen on testosterone commonly report that adding hCG brings back testicular volume and improves libido and erections, and small studies back up the volume and hormonal changes. The subjective benefits are consistent in practice but less formally studied.
Raising your own testosterone
Some evidencehCG alone is used by urologists in younger hypogonadal men as a fertility-sparing alternative to TRT, and it raises testosterone reliably in men whose testes still respond. It is a legitimate route for the right man, with the same estradiol management issues as any hCG use.
How it works
- Used to support natural testosterone and fertility
- Often used alongside testosterone therapy
- A prescription medicine with solid clinical use
- This one genuinely belongs under a doctor’s supervision
How people use it
Safety, in brief
Things people sometimes notice
- A little soreness where you inject
- Mild water retention for the first few weeks
- Acne or oilier skin, more so at higher doses
- A moodier week when estradiol climbs
The full picture — stop signs and who should talk to a doctor first — is on the dosing guide.
Sources
The labels and studies behind this page. Each link opens the original on PubMed, DailyMed or ClinicalTrials.gov.
- Novarel (chorionic gonadotropin) prescribing information
- Low-dose human chorionic gonadotropin maintains intratesticular testosterone in normal men with testosterone-induced gonadotropin suppression
- Concomitant intramuscular human chorionic gonadotropin preserves spermatogenesis in men undergoing testosterone replacement therapy
- The effect of human chorionic gonadotropin (HCG) in the treatment of obesity by means of the Simeons therapy: a criteria-based meta-analysis