At a glance
| Hormone family | Glycoprotein gonadotropin |
|---|---|
| Target | LH/hCG receptor |
| Female use | Selected ovulation-induction settings |
| Male use | Selected hypogonadotropic hypogonadism |
| Major fertility risk | Ovarian hyperstimulation syndrome |
| Weight loss | No established therapeutic benefit |
Overview
hCG is naturally produced during pregnancy, but pharmaceutical hCG is used for specific reproductive indications. The US Pregnyl label includes ovulation induction in selected anovulatory infertility, certain cases of male hypogonadotropic hypogonadism, and selected prepubertal cryptorchidism without an anatomical obstruction. These are distinct clinical situations requiring assessment of the underlying cause. Urine-derived hCG and recombinant chorionic gonadotropin products have their own formulations and labeling. hCG acts directly on the gonads, so its effects differ from GnRH medicines that act mainly through the pituitary. A raised testosterone measurement alone does not establish improved fertility.
How it works
hCG binds the luteinizing hormone/choriogonadotropin receptor. In testicular Leydig cells, receptor activation stimulates steroid production, including testosterone. In the ovary, it can trigger final follicular maturation, ovulation and luteinization after appropriate follicular development. Its alpha and beta protein subunits and attached carbohydrate groups distinguish this glycoprotein from short synthetic research peptides. Receptor activity does not make it an effective fat-loss hormone.
Which indications are actually approved?
Pregnyl is labeled for selected anovulatory infertility after appropriate ovarian stimulation, certain male hypogonadotropic-hypogonadism cases, and selected prepubertal cryptorchidism not caused by anatomical obstruction. The diagnostic category matters: stimulating the gonads cannot reliably correct primary ovarian failure or every cause of infertility.
Supporting sources [1]
What does the evidence not support?
The prescribing information explicitly rejects hCG as an effective adjunct for obesity. FDA also warns against hCG weight-loss products. Changes associated with severely restricted diets do not establish a drug effect on fat distribution, appetite or durable weight control.
What are the main treatment risks?
In ovarian stimulation, hCG can contribute to ovarian hyperstimulation syndrome, which can become severe, and multiple pregnancy is a concern. Thromboembolic events, fluid retention, gynecomastia and precocious puberty are among relevant risks. Treatment requires condition-specific monitoring rather than interpretation of a single hormone number.
Supporting sources [1]
Is hCG equivalent to testosterone replacement?
No. hCG stimulates LH receptors and can increase endogenous testicular testosterone when responsive tissue is present; testosterone replacement supplies the hormone directly. Their effects on fertility and feedback signaling differ. Whether hCG is appropriate depends on diagnosis, and evidence for one labeled indication does not validate every combined hormone regimen.
Supporting sources [1]
Reading this profile
Jurisdiction: United States; indications and availability vary by formulation and country.. Molecular class: Glycoprotein hormone composed of alpha and beta subunits.
This profile was written with AI-assisted research and checked against the linked sources. It has not been represented as a clinician’s review. Evidence summaries describe the cited studies and products; they do not establish that a separately purchased preparation is equivalent.
Sources & references
Follow the original material. Product labels define specific formulations and uses; trial registration describes a study and does not by itself establish benefit.
- Pregnyl — current US prescribing information ↗Regulatory source · Checked 2026-10-27
- FDA — questions and answers on hCG products for weight loss ↗Regulatory source · Checked 2026-10-27