An hCG injection delivers human chorionic gonadotropin, a pregnancy hormone that acts almost exactly like the body’s luteinizing hormone (LH).[1] It is a prescription drug in the US for undescended testes in boys, low testosterone caused by a pituitary problem in men, and ovulation induction in women.[1][3] Doctors also prescribe hCG for men on testosterone therapy to protect fertility, an off-label use backed by small studies.[15] The popular “hCG diet” is not supported: the labels and controlled trials show no added weight loss.[1][13]
This profile covers what hCG is, approved uses, hCG for men, the hCG diet, dosage, side effects, how it compares with hMG and kisspeptin-10, and the law.
What is hCG?
hCG is made by the placenta. It has two parts: an alpha subunit shared with LH, FSH and TSH, and a beta subunit unique to hCG.[1] Novarel and Pregnyl are purified from the urine of pregnant women and injected into muscle.[1][2] Ovidrel (choriogonadotropin alfa) is made by recombinant DNA technology and injected under the skin.[3]
In men, hCG prompts the testes’ Leydig cells to make testosterone. In women, it can replace the mid-cycle LH surge that triggers ovulation, and it supports the corpus luteum.[1] Because it acts on the hormonal axis, it sits in our hormonal peptides and sexual health categories.
FDA has approved these brands:
- Novarel (Ferring, 1974) and Pregnyl (Organon, 1976): prepubertal cryptorchidism (undescended testes not caused by a blockage), selected cases of hypogonadotropic hypogonadism in males, and ovulation induction after pretreatment with menotropins or other gonadotropins.[4][5][1][2]
- Ovidrel (EMD Serono, 2000): triggering final egg maturation in IVF and other assisted reproduction, and ovulation induction.[6][3]
For undescended testes, the labels note that descent after hCG is often temporary.[1] The 2014 AUA guideline recommends surgery (orchiopexy) and does not recommend hormonal therapy.[23]
hCG for men: hypogonadism and testosterone therapy
Hypogonadotropic hypogonadism
When the pituitary makes too little LH and FSH, hCG can restore testosterone, and adding FSH helps start sperm production. A 2025 meta-analysis of 41 studies (1,673 men) found that 78% produced sperm after a median of 18 months of gonadotropin treatment. Only 24% reached more than 10 million sperm per mL, and hCG plus FSH outperformed hCG alone.[20] In a Russian study of 8 teenage boys with congenital hypogonadotropic hypogonadism, 12 months of hCG plus recombinant FSH raised median testosterone from 0.44 to 4.39 nmol/L and started puberty.[22]
Protecting fertility on testosterone
Testosterone therapy suppresses LH and FSH, which can stop sperm production. The Endocrine Society recommends against starting testosterone in men planning fertility in the near term.[19] The AUA testosterone deficiency guideline[17], as quoted in a 2025 review, says clinicians may use aromatase inhibitors, hCG, SERMs or a combination in testosterone-deficient men who want to maintain fertility (a conditional recommendation based on Grade C evidence). The same review notes that the 2024 AUA/ASRM male infertility guideline considers the evidence for adding hCG to testosterone insufficient.[18]
The evidence behind adding hCG:
- Testicular testosterone: in 29 healthy men on weekly testosterone, testicular testosterone fell 94% without hCG. With 250 IU hCG every other day, it stayed within 7% of baseline.[14]
- Semen: in a retrospective series of 26 hypogonadal men on testosterone plus 500 IU hCG every other day, semen measures did not change, nobody became azoospermic, and 9 contributed to a pregnancy.[15]
- Recovery after testosterone: in 49 men with testosterone-related azoospermia or very low counts, sperm returned or counts improved in 95.9% on hCG-based combination therapy (3,000 IU hCG every other day plus other drugs), on average within 4.6 months.[16]
- Russian data: a 2025 study from Russia’s National Medical Research Center for Endocrinology followed 53 men for more than 5 years. Sperm concentration fell on testosterone alone, but held steady with courses of testosterone plus hCG; motility and shape worsened in both groups.[21]
These are small or uncontrolled studies, and none of these uses for men already on testosterone is on the US label.
hCG diet: myth vs evidence
The hCG diet traces back to A.T.W. Simeons, who described hCG for obesity in The Lancet in 1954.[10] It pairs hCG with a diet of about 500 calories a day.[11]
| Claim | What the evidence shows |
|---|---|
| hCG boosts weight loss | Labels: no substantial evidence of weight loss beyond calorie restriction.[1] A double-blind trial in 51 women found no difference from placebo.[11] |
| hCG targets “abnormal” fat | Labels: no known effect on fat mobilization or fat distribution.[2] |
| hCG stops hunger on 500 calories | Hunger ratings did not differ from placebo in two double-blind trials.[11][12] |
| Studies support it | A meta-analysis of 24 trials found mostly poor-quality studies; only 1 of the 12 better ones favored hCG.[13] |
| Drops and sprays work | FDA says “homeopathic” hCG products are illegally marketed and unproven.[8] |
Any weight lost comes from the severe calorie cut. FDA warns that very low calorie diets raise the risk of gallstones, electrolyte imbalance and irregular heartbeat.[9] For drugs that do work for weight loss, see semaglutide and tirzepatide, or our weight loss peptides page.
hCG dosage
hCG is measured in USP or international units (IU). The labels list these regimens, given into muscle:[1][2]
| Use (Novarel/Pregnyl label) | Regimen |
|---|---|
| Hypogonadotropic hypogonadism in males | 500 to 1,000 units 3 times a week for 3 weeks, then twice a week for 3 weeks; or 4,000 units 3 times a week for 6 to 9 months, then 2,000 units 3 times a week for 3 more months |
| Prepubertal cryptorchidism (ages 4 to 9) | For example, 4,000 units 3 times a week for 3 weeks, or 500 units 3 times a week for 4 to 6 weeks |
| Ovulation induction | 5,000 to 10,000 units one day after the last menotropins (or other gonadotropin) dose |
Ovidrel is given as a single 250 microgram dose under the skin, one day after the last FSH dose.[3] Doses used with testosterone in studies were 250 to 500 IU every other day.[14][15]
A 10,000-unit Novarel vial mixed with 10 mL of bacteriostatic water gives 1,000 units per mL; refrigerate and use within 30 days.[1] To convert units to syringe markings, use our peptide calculator.
hCG side effects
- Headache, irritability, restlessness, depression and fatigue
- Fluid retention (edema), and occasional water and salt retention at high doses in men
- Breast enlargement (gynecomastia) in men
- Pain, bruising or redness at the injection site
- Allergic reactions, including anaphylaxis
- Early puberty in boys treated for undescended testes
In women, hCG used after fertility drugs can cause ovarian hyperstimulation syndrome (OHSS), multiple births and blood clots.[1][3] There are sporadic reports of testicular tumors in young men given hCG for infertility, but a causal link has not been shown.[1] hCG should not be used with prostate cancer or other androgen-dependent tumors.[1]
hCG vs hMG and kisspeptin
hCG supplies only LH-like activity. hMG (menotropins) supplies both FSH and LH activity, which is why it is paired with hCG to drive sperm production or egg development. Kisspeptin-10 works one step higher, prompting the brain to release the body’s own LH, but it remains investigational.
Is hCG legal?
- Prescription only: hCG is approved only as a prescription injection.[7]
- No legal OTC or diet product: in December 2011, FDA and the FTC issued seven warning letters to firms selling “homeopathic” hCG drops, pellets and sprays for weight loss.[7] FDA states that there are no FDA-approved hCG products for weight loss.[8]
- Banned in sport for men: WADA’s 2026 list bans chorionic gonadotrophin and LH in males under S2.2.1, at all times.[24]
This is general information, not legal advice.
