hCG

A pregnancy hormone that mimics LH — prescribed alongside TRT to keep the testes working and fertility alive, and used in PCT to restart production. The one compound in the steroid-adjacent world with a genuinely defensible medical logic for co-use.

hCG is a hormone made in pregnancy that happens to be a near-perfect mimic of LH, the pituitary signal that tells the testes to make testosterone. That single fact explains all of its uses and misuses. Given to a man whose own LH is suppressed, it bypasses the shut-down pituitary and stimulates the testes directly while it is present — it does not restart hypothalamic or pituitary signalling, and post-androgen hypogonadism is a medical problem needing evaluation, not an injection schedule. It has no direct fat-loss mechanism whatsoever, which makes the diet industry built on it one of the clearest examples of a claim with no pharmacological basis at all.

Solid: maintains intratesticular testosterone and semen parameters on TRT, and restores testicular function after suppression. Fertility-clinic literature is extensive. The fringe "hCG diet" use is completely discredited — that part is a scam with a hormone attached.

• Well established for specific endocrine and fertility indications, including stimulating ovulation and treating certain forms of hypogonadism. That is real, approved medicine.
• LIMITED evidence for the TRT-adjunct use, and it is worth being precise about how limited: the intratesticular-testosterone finding is a 29-man three-week study that measured no semen outcome, the semen-preservation finding is a 26-man retrospective series, and the recovery-after-testosterone report used hCG as part of combination therapy in 49 men, so nothing there isolates hCG. Maintaining sperm concentration is also not the same thing as demonstrated fertility — conception was never the endpoint.
• The weight-loss claim has been tested and failed repeatedly. Controlled trials comparing hCG against placebo alongside a very low calorie diet found no difference in weight lost, fat lost, or hunger — the weight came from the starvation diet, not the hormone.
• FDA requires hCG weight-loss products to carry a statement that there is no substantial evidence it increases weight loss beyond calorie restriction, and has acted against homeopathic hCG products entirely.
• The hCG diet protocols pair it with dangerously severe calorie restriction, which carries its own documented risks — gallstones and electrolyte disturbance among them — independent of the hormone.

Given by injection, since it is a glycoprotein hormone that would not survive digestion, with a half-life long compared with LH. It is prohibited in male athletes specifically for its testosterone-stimulating effect. hCG is also the hormone pregnancy tests detect, so taking it can cause a false-positive pregnancy-test result.

Estrogen-side effects (it raises E2 production), acne, water retention; overuse desensitizes the very receptors it stimulates. Compounding-pharmacy access tightened after FDA reclassification, pushing users to grey vials of a temperature-sensitive biologic — potency roulette. Needles and reconstitution done casually, as with any peptide-style vial.

• Anyone with a hormone-sensitive cancer, including prostate or breast
• Anyone using it for weight loss, where the evidence is unambiguous that it does nothing
• Anyone considering a very low calorie diet without medical supervision
• Anyone in tested sport, where it is prohibited for men
• Anyone pregnant — the label says it is not indicated in pregnancy and is discontinued once pregnancy is confirmed; fertility treatment is a separate, specialist-supervised context

• Testosterone therapy, which it is most often paired with — the combination is the point, but it raises oestrogen more than testosterone alone.
• Aromatase inhibitors, frequently stacked to manage that oestrogen rise.
• Fertility treatment generally, where it should be managed by the clinician running it.
• Pregnancy tests, which it will make positive regardless of who takes it.

• This is a prescription hormone whose use needs a clinician — monitoring lists do not make self-use acceptable. Under supervision, what gets followed: testosterone and oestradiol, since stimulating the testes raises both and the oestrogen rise can be substantial.
• Haematocrit.
• Testicular size and, where fertility is the goal, a semen analysis, which is the only measure that answers the actual question.
• Injection sites for infection — and the label-level hazards my summary would otherwise miss: anaphylaxis, fluid retention needing caution in heart or kidney disease and in hypertension, epilepsy, migraine or asthma; in women, ovarian hyperstimulation syndrome, ovarian torsion, blood clots, multiple and ectopic pregnancy.
• For anyone on a very low calorie diet alongside it: electrolytes and gallbladder symptoms, which are the real risks in that protocol.

Testicular stimulation stops and testosterone falls back to whatever the underlying axis supports, which for someone whose own pituitary signalling is still suppressed can mean falling into a hypogonadal gap. That is why stopping it after testosterone therapy is a clinician's problem rather than a scheduling decision. There is no withdrawal syndrome from the hormone itself. Anyone who was using it alongside a very low calorie diet will regain weight when normal eating resumes, since the diet was doing the work.

US: prescription biologic. Post-2020 it is a biologic legally — compounded versions largely ended, which is why supply talk dominates forums.

Papers about this compound, not proof of the claims above. A title says what was studied, which is sometimes a negative result or a different question entirely.

• Human Chorionic Gonadotropin as a Marker of Parathyroid Carcinoma: Findings From a Scoping Review
  Cureus, 2025
• Human Chorionic Gonadotropin
  2026

• Human Chorionic Gonadotropin-Mediated Immune Responses That Facilitate Embryo Implantation and PlacentationFront Immunol · 2019
• Human Chorionic Gonadotropin and Breast CancerInt J Mol Sci · 2017
• Human Chorionic Gonadotropin2026
• Human chorionic gonadotropin-based clinical treatments for infertile men with non-obstructive azoospermiaAndrology · 2026
• Differential diagnosis of elevated human chorionic gonadotropin in womenCase Rep Womens Health · 2023
• β-Human Chorionic Gonadotropin Dynamics in Early Gestational Events: A Practical and Updated ReappraisalObstet Gynecol Int · 2024
• Human Chorionic Gonadotropin as a Marker of Parathyroid Carcinoma: Findings From a Scoping ReviewCureus · 2025
• Human Chorionic Gonadotropin as a Pivotal Endocrine Immune Regulator Initiating and Preserving Fetal ToleranceInt J Mol Sci · 2017
• Human Chorionic Gonadotropin (hCG)-An Endocrine, Regulator of Gestation and CancerInt J Mol Sci · 2018
• The Utility of Monitoring Beta-Human Chorionic Gonadotropin Levels in an Ectopic PregnancyCureus · 2023
• Determination of human chorionic gonadotropinBest Pract Res Clin Endocrinol Metab · 2013
• Research Progress on the Impact of Human Chorionic Gonadotropin on Reproductive Performance in SowsAnimals (Basel) · 2024