Human chorionic gonadotropin

What it is

Human chorionic gonadotropin, abbreviated hCG, is a placental glycoprotein hormone best known as the hormone detected by pregnancy tests. It is produced during pregnancy and helps maintain corpus luteum progesterone production early in gestation^{[1 –3 ]}. In drug form, hCG is used because its biologic activity closely resembles luteinizing hormone, or LH, one of the key pituitary gonadotropins involved in ovulation and testicular steroidogenesis^{[1 –3 ]}.

hCG is not a peptide in the narrow sense of a small linear amino-acid chain. It is a heterodimeric glycoprotein hormone composed of noncovalently linked alpha and beta subunits. The alpha subunit is closely related to those of LH, follicle-stimulating hormone, and thyroid-stimulating hormone, while the beta subunit gives hCG its specific biologic and immunologic identity^{[1 –3 ]}. Because it is a hormone protein used in injection-based reproductive and endocrine medicine, it is often discussed alongside peptide therapies in clinical and consumer contexts.

Mechanism

At the receptor level, hCG binds the LH/choriogonadotropin receptor. In the ovary, this signaling can substitute for the mid-cycle LH surge, supporting final follicular maturation, resumption of oocyte meiosis, follicle rupture, and luteinization in appropriately selected fertility-treatment cycles^{[2 –3 ]}. In the testis, hCG stimulates Leydig cells to produce testosterone and other androgens^{[1 –2 ]}. These mechanisms underpin FDA-approved uses in ovulation induction, assisted reproductive technology, selected cases of male hypogonadotropic hypogonadism, and prepubertal cryptorchidism not due to anatomic obstruction^{[1 –3 ]}.

Approved products

Pregnyl and Novarel are urinary-derived chorionic gonadotropin products administered intramuscularly after reconstitution^{[1 –2 ]}. Ovidrel is recombinant choriogonadotropin alfa supplied as a prefilled syringe for subcutaneous injection in fertility treatment^{[3 ]}. Product details here are informational, not dosing guidance.

hCG is also one of the most misrepresented hormone products in popular weight-loss culture. FDA states that there are no FDA-approved hCG products for weight loss, that hCG has not been demonstrated to be effective therapy for obesity, and that OTC products labeled as homeopathic hCG for weight loss are illegally marketed^{[4 –5 ]}.

Regulatory status

hCG is FDA-approved by prescription in several injectable products. Pregnyl and Novarel labeling lists three core indications: prepubertal cryptorchidism not due to anatomic obstruction; selected cases of hypogonadotropic hypogonadism in males; and induction of ovulation and pregnancy in anovulatory infertile women whose anovulation is secondary rather than due to primary ovarian failure and who have been appropriately treated with human gonadotropins^{[1 –2 ]}. Ovidrel is approved for induction of final follicular maturation and early luteinization in infertile women undergoing assisted reproductive technology, and for induction of ovulation and pregnancy in anovulatory infertile patients whose infertility is functional and not due to primary ovarian failure^{[3 ]}.

Approved hCG products are prescription-only. FDA’s hCG weight-loss Q&A states that FDA-approved hCG products are available only in injectable form and require a prescription from a licensed medical professional^{[4 ]}. FDA also states that no hCG products are FDA-approved for weight loss and that prescription hCG products are not approved for any weight-loss use^{[4 –5 ]}.

Compounding context

Compounding analysis should distinguish approved-drug availability from lawful compounding. FDA states that 503A pharmacies and physicians using bulk drug substances must use substances that comply with an applicable USP/NF monograph, are components of FDA-approved drugs if no monograph exists, or appear on FDA’s 503A bulks list^{[6 ]}. For 503B outsourcing facilities, FDA states that bulk substances may be used only if the substance appears on the 503B bulks list or the compounded drug appears on FDA’s shortage list at the time of compounding, distribution, and dispensing^{[6 –7 ]}. Because FDA-approved hCG products exist, routine compounded copies may raise statutory “essentially a copy” and biologic/drug-product issues that require product-specific legal review.

Controlled-substance and anti-doping status

hCG is not listed as a DEA-controlled substance on DailyMed labeling for Pregnyl, Novarel, or Ovidrel, each of which reports DEA Schedule as None^{[1 –3 ]}. It is also not listed in the federal controlled-substance schedules reviewed in 21 CFR Part 1308^{[8 ]}. This does not mean hCG is over-the-counter; it remains a prescription drug.

In sport, anti-doping status differs from FDA status. hCG is prohibited for male athletes under the World Anti-Doping Agency prohibited list because it can increase endogenous testosterone production^{[9 ]}.

Last regulatory verification: May 5, 2026.

Research summary

hCG has a long clinical history in reproductive medicine. In ovulation induction and assisted reproduction, hCG is used to mimic the LH surge after follicular development has been monitored. Ovidrel labeling states that choriogonadotropin alfa binds LH/hCG receptors on granulosa and theca cells and initiates final follicular maturation and luteinization when adequate follicular development has occurred after FSH treatment^{[3 ]}. The clinical role is therefore closely tied to monitoring protocols, patient selection, and other fertility medications rather than standalone use.

Recombinant vs. urinary hCG for trigger

A 2016 Cochrane review by Youssef and colleagues evaluated recombinant hCG or recombinant LH compared with urinary hCG for final oocyte maturation triggering in IVF and ICSI cycles. The review included 18 randomized trials with 2,952 women; 15 trials compared recombinant hCG with urinary hCG, and three compared recombinant LH with urinary hCG^{[10 ]}. The authors concluded that there was no evidence of a difference between recombinant hCG or recombinant LH and urinary hCG for live birth or ongoing pregnancy rates or ovarian hyperstimulation syndrome^{[10 ]}. Evidence quality varied, with moderate quality for ongoing pregnancy/live birth in the recombinant hCG comparison and lower quality for OHSS and recombinant LH comparisons^{[10 ]}.

hCG during follicular stimulation

Research has also evaluated hCG as part of follicular stimulation rather than only as a final trigger. A 2012 systematic review and meta-analysis included 11 randomized controlled trials and 1,068 women receiving hCG during early or late follicular phases in assisted reproduction protocols^{[11 ]}. The authors found no differences in live birth, miscarriage, or OHSS rates between hCG and comparator regimens, while clinical pregnancy favored late-follicular hCG in pooled analysis^{[11 ]}. These findings are protocol-specific and should not be translated into general claims outside reproductive endocrinology.

Male hypogonadotropic hypogonadism

In males with hypogonadotropic hypogonadism, hCG is used because it stimulates Leydig-cell testosterone production through LH/hCG receptor signaling^{[1 –2 ]}. A 2024 systematic review and meta-analysis of gonadotropins for pubertal induction in males with hypogonadotropic hypogonadism screened 3,925 abstracts and included 103 studies representing 5,328 patients^{[12 ]}. hCG was used in 90.3% of included studies, and gonadotropins induced significant increases in testicular volume, penile size, and testosterone in more than 98% of analyses^{[12 ]}. Spermatogenesis rates were higher with hCG plus FSH than with hCG alone, but the authors emphasized substantial heterogeneity in treatment choice, dose, duration, and outcomes^{[12 ]}.

Fertility preservation during testosterone therapy

hCG is also discussed in male fertility preservation when exogenous testosterone suppresses LH and FSH. A review by Ramasamy, Armstrong, and Lipshultz summarized evidence that exogenous testosterone can suppress spermatogenesis and that hCG can maintain intratesticular testosterone in some men receiving testosterone therapy^{[13 ]}. A small randomized trial by Coviello and colleagues found that low-dose hCG maintained intratesticular testosterone in healthy men receiving testosterone-induced gonadotropin suppression^{[14 ]}. These findings support why reproductive urologists discuss hCG in selected fertility contexts, but they do not establish hCG as a general “testosterone optimization” drug for all men.

Cryptorchidism

For cryptorchidism, the evidence is more contested. Pregnyl and Novarel remain labeled for prepubertal cryptorchidism not due to anatomic obstruction^{[1 –2 ]}. However, a 2018 meta-analysis of randomized controlled trials found low-quality evidence and concluded that hCG treatment was not superior to placebo and did not differ significantly from GnRH treatment in the analyzed trials^{[15 ]}. This does not erase the approved indication, but it does mean editorial discussion should acknowledge that modern evidence and practice have become more cautious, with surgical orchiopexy often central in contemporary management.

Weight loss — negative evidence

The weight-loss evidence is negative. Young, Fuchs, and Woltjen published a double-blind crossover study in JAMA in 1976 involving 202 patients and found no statistically significant difference between hCG and placebo in a weight-reduction program^{[16 ]}. Shetty and Kalkhoff published a controlled inpatient study in 1977 in which hCG plus a 500-calorie diet produced weight loss nearly identical to placebo plus the same diet, with no advantage in body measurements or measured metabolic parameters^{[17 ]}. Miller and Schneiderman likewise found hCG no better than saline in a double-blind crossover study^{[18 ]}. FDA’s current position reflects this evidence: hCG has not been demonstrated to be effective therapy for obesity, and there is no substantial evidence that it increases weight loss beyond calorie restriction^{[4 –5 ]}.

Where the evidence ends

Overall, hCG has strong regulatory and clinical grounding in specific reproductive and endocrine indications, especially fertility treatment and selected male hypogonadotropic hypogonadism. The evidence does not support hCG for weight loss, nonspecific wellness, bodybuilding, or broad hormone optimization outside medically supervised contexts.

Public discourse

Carolyn Becker, FDA Center for Drug Evaluation and Research official, addressed hCG products marketed for weight loss in an FDA consumer update and emphasized that observed weight loss in hCG diet plans is attributable to severe calorie restriction rather than hCG^{[5 ]}.

Kyle Gillett, MD, family medicine and obesity medicine physician, discussed hCG in the context of testosterone, fertility, and LH suppression on the Huberman Lab podcast^{[19 ]}.

The Practice Committee of the American Society for Reproductive Medicine has framed hCG as a trigger for ovulation after follicular development in monitored gonadotropin cycles^{[20 ]}, while a separate 2024 ASRM guideline on prevention of moderate and severe ovarian hyperstimulation syndrome describes hCG trigger strategies and OHSS risk-reduction alternatives^{[21 ]}.

Public discourse reflects the views of the speakers cited and does not represent medical advice or the editorial position of ProPeptideGuide.

Side effects and safety

Safety considerations depend heavily on sex, indication, dose, product, and whether hCG is used with other gonadotropins. In fertility treatment, hCG is a potent ovulatory trigger and is associated with ovarian enlargement, ovarian hyperstimulation syndrome, multiple gestation, and thromboembolic events in rare cases, particularly when used after follicular stimulation^{[1 –3 ,21 ]}. Ovidrel labeling states that safe and effective use requires monitoring of ovarian response with serum estradiol and transvaginal ultrasound^{[3 ]}.

Common adverse reactions and warnings

Pregnyl labeling lists hypersensitivity reactions, including anaphylaxis, injection-site reactions, headache, irritability, restlessness, depression, edema, fatigue, and rare thromboembolism associated with FSH/hCG therapy, usually in association with severe OHSS^{[1 ]}. Novarel labeling is similar because it contains urinary-derived chorionic gonadotropin^{[2 ]}.

In males, hCG-induced androgen production can cause fluid retention. Pregnyl labeling advises caution in patients with cardiac or renal disease, hypertension, epilepsy, migraine, or asthma^{[1 ]}. Pediatric use for cryptorchidism may induce precocious puberty; labeling states therapy should be discontinued if signs of precocious puberty occur^{[1 ]}.

Contraindications

Contraindications differ by product and population. Pregnyl contraindications include prior hypersensitivity to human gonadotropins, high serum FSH indicating primary gonadal failure in women, uncontrolled non-gonadal endocrinopathies, certain hypothalamic/pituitary and sex-hormone-related tumors, reproductive-organ malformations incompatible with pregnancy, fibroid tumors incompatible with pregnancy, and abnormal vaginal bleeding of undetermined origin^{[1 ]}. Ovidrel is contraindicated in women with prior hypersensitivity to hCG preparations or excipients, primary ovarian failure, uncontrolled thyroid or adrenal dysfunction, uncontrolled organic intracranial lesions such as pituitary tumor, abnormal uterine bleeding of undetermined origin, ovarian cyst or enlargement of undetermined origin, sex hormone-dependent tumors, and pregnancy^{[3 ]}.

Weight-loss-specific safety

Weight-loss use introduces a separate safety problem. FDA states that hCG weight-loss products are not approved, that OTC homeopathic hCG products are illegally marketed, and that very-low-calorie diets used with hCG products increase risks including gallstones, electrolyte imbalance, and heart arrhythmias^{[4 –5 ]}. FDA also reports serious adverse events associated with hCG injections for weight loss, including pulmonary embolism, depression, cerebrovascular issues, cardiac arrest, and death^{[4 ]}.

Long-term safety

Long-term safety data are strongest in regulated fertility and endocrine use, not in unsupervised weight-loss, bodybuilding, or hormone-optimization contexts. Risks from unapproved products include incorrect identity, contamination, dosing errors, nonsterile injection practices, and lack of appropriate monitoring.

Available through

FDA-approved hCG products are available in the United States by prescription through licensed clinicians and pharmacies when used within applicable prescribing rules and product labeling^{[1 –3 ]}.

Provider-platform listings will be added only after legal and editorial verification confirms that the platform uses licensed clinicians, compliant pharmacy channels, and FDA-approved products for appropriate indications. ProPeptideGuide does not link to or endorse OTC homeopathic hCG products, hCG diet products, bodybuilding vendors, research-chemical sellers, or non-prescription injectable hormone sources. There are no FDA-approved hCG products for weight loss^{[4 –5 ]}.