Pregnancy hormone that acts like LH. Used to trigger ovulation in fertility treatments and in some cases of male hypogonadism and cryptorchidism. It does not work for weight loss.
Regulatory status
Approved (FDA / EMA)
Family
Glycoprotein hormone (gonadotropin with LH-like action)
FDA (US): Approved: urinary hCG (Pregnyl, Novarel) for ovulation induction, male hypogonadotropic hypogonadism, and prepubertal cryptorchidism; recombinant choriogonadotropin alfa (2000, Ovidrel). Not approved for weight loss: in 2011 the FDA declared over-the-counter 'hCG' diet products illegal
EMA (EU): Approved (2001, Ovitrelle, choriogonadotropin alfa) for final follicular maturation and luteinization in assisted reproduction; urinary hCG is authorized nationally
Dose
Triggering ovulation in assisted reproduction: Ovitrelle 250 µg subcutaneously as a single dose (EMA label); urinary hCG 5,000–10,000 IU according to the label. Other indications according to the label. For weight loss: no established dose, because it is not effective.
Safety
Women: ovarian hyperstimulation syndrome, multiple pregnancy, ectopic pregnancy, thromboembolism. Men/children: gynecomastia, fluid retention, precocious puberty if used in excess in children. Use under medical supervision; do not buy 'hCG' products for diets.
Interactions
May give false positives on pregnancy tests for a few days after the injection.
Differences between women and men
Used differently depending on sex: in women to induce ovulation (with a risk of ovarian hyperstimulation and multiple pregnancy); in men for hypogonadotropic hypogonadism and in boys for cryptorchidism. Contraindicated in sex-hormone-dependent tumors (e.g., of the ovary, breast, uterus, or prostate).
Effect by goal · level of evidence
hCG diet: does not help with weight loss
no clear effectHighmeta-analysis (AAA)in people
No effect
A meta-analysis of 24 studies (8 controlled) found no evidence that hCG increases weight loss, redistributes fat, reduces hunger, or improves well-being compared with diet alone. The higher-quality studies were almost without exception negative.
Binds to the LH receptor. In women it triggers final egg maturation and ovulation about 36 hours later, and sustains the corpus luteum. In men it stimulates the testes to produce testosterone and support sperm formation.
What the evidence says
In people
The hCG diet: it does not help with weight loss. A meta-analysis of 24 studies (8 controlled) found no evidence that hCG increases weight loss, redistributes fat, reduces hunger, or improves well-being compared with diet alone. The higher-quality studies were almost without exception negative. PubMed 8527285
Variants and related programs
Popular unapproved use: the 'hCG diet' (Simeons method), which combines injections or drops with a diet of about 500 kcal. The evidence shows that the weight loss is due to the diet, not to hCG.