Evidence memo / Reproductive & endocrine

Human chorionic gonadotropin (hCG)

Also: hCG · Pregnyl · Novarel · chorionic gonadotropin

A glycoprotein hormone approved (as Pregnyl, Novarel, and others) for specific uses such as hypogonadotropic hypogonadism and induction of ovulation. Its endocrine biology is well established. It is also attached to claims the evidence does not support, most notably hCG weight-loss products, which the FDA has called illegal and fraudulent. The Watchlist boundary is separating the approved endocrine and fertility uses from the diet and performance claims.

Approved for specific usesApproved specific useSafety / regulatory watch

The verdict

Our read at a glance.

Whether hCG's approved endocrine and fertility uses support the separate weight-loss and testosterone or performance claims commonly attached to it.

The signal
The approved uses, including induction of ovulation and treatment of hypogonadotropic hypogonadism, rest on established endocrine pharmacology and long clinical use. For weight loss, controlled studies and regulators have found no benefit beyond a very low calorie diet alone, and the FDA has acted against over-the-counter hCG weight-loss products.
The unknown
Less about whether hCG works for its approved endocrine uses, which is established, and more about how persistently the weight-loss and performance claims survive despite negative evidence and regulatory action.
Our read
Two separate stories under one name. hCG is a real, approved endocrine and fertility drug, and at the same time the hCG diet is a long-debunked claim the FDA has acted against. The error to avoid is letting the legitimate uses lend credibility to the weight-loss and performance claims.

The mechanism

How it works.

hCG is a glycoprotein hormone normally made by the placenta in pregnancy. It binds the LH/hCG receptor on the gonads, the same receptor luteinizing hormone uses, and switches on gonadal hormone production. In women this triggers the final maturation and release of an egg, and in men it drives the testes to make testosterone, which is the basis for its approved fertility and hypogonadism uses. It has no mechanism that burns fat, and the hCG diet claims fail in controlled studies.

Safety & regulatory boundary

The consequential part.

The FDA has stated that over-the-counter hCG products marketed for weight loss are illegal and that homeopathic hCG weight-loss products are fraudulent. Approved hCG products such as Pregnyl and Novarel are prescription drugs for defined endocrine and fertility uses and carry warnings including thromboembolism and ovarian hyperstimulation. Approved injectable hCG is not the same as compounded, research-labeled, or homeopathic hCG products, and the approved endocrine uses do not validate weight-loss or performance claims.

What's next

What we're watching.

Continued FDA enforcement against weight-loss hCG products, and whether fertility and hypogonadism evidence stays distinct from diet and bodybuilding claims.

Context

Why this is discussed.

hCG is discussed in two very different worlds: approved fertility and endocrine medicine, and the popular but unsupported hCG diet and bodybuilding scenes.

The evidence base

22 cited references.

Regulatory & labels2

DailyMed label: Chorionic Gonadotropin

NuCare Pharmaceuticals,Inc. (FDA label) · 2025

DailyMed label: Chorionic Gonadotropin

Fresenius Kabi USA, LLC (FDA label) · 2025

Indexed literature (PubMed)12

Recombinant gonadotropins

McClamrock HD · Clin Obstet Gynecol · 2003

Human Chorionic Gonadotropin and Breast Cancer

Schüler-Toprak S et al. · Int J Mol Sci · 2017

Keep reading

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