Chorionic Gonadotropin (Human)

Summary

Human chorionic gonadotropin (hCG) is a naturally occurring glycoprotein hormone produced by the placenta during pregnancy. As a pharmaceutical, it is used to trigger ovulation in women undergoing assisted reproduction, treat hypogonadotropic hypogonadism in males, and manage cryptorchidism in prepubertal boys. It shares the same alpha subunit as LH, FSH, and TSH, with a unique beta subunit conferring its specificity.

Mechanism of Action

Binds and activates luteinizing hormone/choriogonadotropin receptors (LHCGR) on Leydig cells in the testes and granulosa/theca cells in the ovaries, stimulating steroidogenesis (testosterone production in males, estrogen and progesterone in females) and triggering ovulation via a LH-surge-like effect.

Routes of Administration

Goals & Uses

• Ovulation induction / ART triggerReproductive EndocrinologyHigh
• Corpus luteum support in ARTReproductive EndocrinologyHigh
• Testosterone optimization / fertility preservation during TRTMen's Health (off Label)Moderate
• Treatment of hypogonadotropic hypogonadism in malesEndocrinology / AndrologyHigh
• Cryptorchidism treatmentPediatric UrologyModerate

Contraindications

• Hypersensitivity to hCG or excipientsAllergy/ImmunologyHigh
• Ovarian hyperstimulation syndrome (OHSS) riskReproductive MedicineHigh
• Primary gonadal failure (hypergonadotropic hypogonadism)EndocrinologyHigh
• Uncontrolled thyroid or adrenal dysfunctionEndocrinologyModerate
• Hormone-sensitive malignancies (e.g., prostate cancer, testicular germ cell tumors)OncologyHigh
• Precocious pubertyPediatric EndocrinologyHigh

Adverse Effects

• Injection site reactionsLocalCommon
• Multiple gestationReproductiveUncommon
• HeadacheNeurologicCommonPain in the head or upper neck
• Thromboembolic eventsCardiovascularRare
• GynecomastiaEndocrineUncommon
• Ovarian hyperstimulation syndrome (OHSS)ReproductiveUncommon

Drug Interactions

• Exogenous testosterone (TRT)Low
• Aromatase inhibitors (e.g., anastrozole, letrozole)Low
• Clomiphene citrateLow
• GnRH agonists / antagonistsLow

Population Constraints

• PregnancyReproductive SafetyRelative
• Renal impairmentOrgan ImpairmentRelative
• Prepubertal childrenPediatricRelative
• Patients with history of thromboembolic diseaseCardiovascularRelative

Regulatory Status

• European UnionApprovedApproved: Anovulation and assisted reproduction (ovulation trigger), Male hypogonadotropic hypogonadism, CryptorchidismApproved by EMA under multiple product names including Pregnyl and Ovitrelle (choriogonadotropin alfa). Subject to EMA pharmacovigilance guidelines.
• United StatesApprovedApproved: Induction of ovulation and pregnancy in anovulatory infertile women, Treatment of hypogonadotropic hypogonadism in males, Prepubertal cryptorchidism not due to anatomical obstructionMultiple urinary-derived (Pregnyl, Novarel) and recombinant (Ovidrel/choriogonadotropin alfa) products approved by FDA. HCG diet/homeopathic formulations are not FDA-approved and have been subject to warning letters.
• United KingdomApprovedApproved: Female infertility / ART ovulation trigger, Male hypogonadotropic hypogonadism, CryptorchidismApproved by MHRA; Pregnyl and Ovitrelle (recombinant) available on prescription. Prohibited in sport per UK Anti-Doping rules consistent with WADA code.

FDA-approved under multiple brand names. Some urinary-derived hCG products have been discontinued (e.g., Pregnyl remains available). Recombinant choriogonadotropin alfa (r-hCG, Ovidrel) is separately approved. hCG is prohibited in sport by WADA (classified as a peptide hormone). Off-label use for weight loss (HCG diet) is not FDA-approved and has been subject to enforcement actions against homeopathic preparations.

Evidence & Sources

No sources recorded yet.