Skip to content
Terminus Peptides
Sign inContact
  • Research use only — not for human or veterinary use
  • 67 compound profiles, every source cited
  • 63 research materials listed
  • Prices published, not hidden behind an enquiry
  • Vials and pre-filled pens
  • Dispatched and supported from the UK
  • Every profile states its UK regulatory status

Research profile · Hormone

HCG

Also known as Human chorionic gonadotropin, Chorionic gonadotrophin

Clinical — evidence level 4 of 4: Established clinical evidencePrescription only — UK regulatory status: Prescription-only medicine (UK)

Overview

A placental glycoprotein hormone acting at the LH/CG receptor. A prescription-only medicine in the UK.

Category
Hormone
Highest evidence level identified
Established clinical evidence
Last scientifically reviewed
22 August 2026
Last regulatory review
22 August 2026

Mechanism under investigation

Human chorionic gonadotropin is a heterodimeric glycoprotein of an alpha subunit shared with LH, FSH and TSH and a hormone-specific beta subunit. It acts at the same receptor as luteinising hormone — the LH/CG receptor, a G-protein-coupled receptor expressed in ovarian theca and granulosa cells and testicular Leydig cells — but binds it with higher affinity and a much longer circulating half-life than LH itself. Receptor activation drives cAMP-mediated steroidogenesis: in women, final follicular maturation and corpus luteum support; in men, testicular testosterone production. The licensed UK product is a recombinant form, choriogonadotropin alfa.

Research areas

  • Reproductive endocrinology

These are fields in which the compound has been investigated. Listing a field is not a statement that anything was demonstrated within it.

Current evidence

In-vitro evidence

Cells, tissues or biochemical systems outside a living organism.

Deeply characterised over decades: receptor cloning, binding kinetics, the structural basis of the LH/hCG functional difference at a shared receptor, and the signalling differences between the two hormones.

Animal evidence

Studies in living non-human animals.

Extensive classical endocrinology across species; hCG-driven Leydig-cell steroidogenesis and ovulation induction are textbook animal pharmacology.

Human observational evidence

Studies observing people without assigning an intervention.

Very large clinical literature across assisted reproduction, including registry data on ovulation triggering and luteal support.

Clinical-trial evidence

Studies assigning an intervention to human participants.

Extensive within reproductive medicine: randomised trials and systematic reviews of hCG as an ovulation trigger and in luteal-phase support underpin the licensed indication. Outside licensed reproductive uses the trial record is thin or negative — most prominently, controlled evidence does not support the hCG diet, a use regulators have acted against.

Study limitations

  • The high-quality evidence is confined to reproductive endocrinology under specialist supervision; popular uses outside it lack controlled support.
  • Ovarian hyperstimulation syndrome is a recognised, occasionally serious complication of triggering ovulation, which is why the licensed product sits behind specialist prescribing.
  • Comparative questions — recombinant versus urinary product, trigger timing, dose — remain active research areas within the specialty.
  • Immunoassay cross-reactivity and preparation heterogeneity complicate older literature, where urinary products of varying purity were the norm.

UK regulatory context

Prescription-only medicine (UK)

A medicine that may lawfully be supplied in the UK only against a prescription from an appropriate practitioner.

Source: Ovitrelle 250 micrograms solution for injection in pre-filled pen — Summary of Product Characteristics (opens medicines.org.uk in a new tab) (electronic Medicines Compendium)

Regulatory classification is jurisdiction-specific. A compound authorised elsewhere is not thereby authorised in the UK, and a supplier’s description of a substance does not determine how it is classified in law. See safety and regulation for the framework and the authoritative sources.

Safety and interpretation

HCG is a UK prescription-only medicine licensed for triggering final follicular maturation and ovulation within monitored fertility treatment. Its principal recognised risk in that setting, ovarian hyperstimulation syndrome, can be serious and is the reason treatment is supervised with ultrasound and endocrine monitoring. In men, hCG stimulates endogenous testosterone and is used within specialist endocrinology; unsupervised use to manipulate the gonadal axis carries endocrine consequences that the licensed framework exists to manage. The safety record belongs to pharmaceutical product under that supervision and does not transfer to research-grade material.

References