hCG
Human chorionic gonadotropin: acts like LH on the testes, so it keeps testosterone and sperm production going, including on TRT.
FDA-approved (Pregnyl, Novarel) for hypogonadotropic hypogonadism, undescended testes and ovulation induction; not approved for weight loss.
Used for
- Keeping testicular size and fertility on TRT
- Restarting natural production after TRT or steroids
- Low testosterone from a pituitary cause
- Fertility treatment in women
How it works
Binds the LH receptor on the testes’ Leydig cells, which make testosterone inside the testes, the level sperm production needs. TRT shuts off LH; hCG stands in for it.
Half-life: about 1–1.5 days
What the research shows
- In men with testosterone-suppressed LH, 250 IU every other day kept testosterone inside the testes near normal (125–500 IU tested).
- In 26 men on TRT, 500 IU every other day kept semen parameters stable over about 6 months; none lost sperm entirely.
Dosing
Dosing isn’t listed on the public site. In the app, each published option is shown with its source (a drug label, a clinical guideline, a trial or community reports) and can be turned into a protocol you review.
Work out the units to draw for your vial →Side effects
- Higher estradiol: breast tenderness, water retention
- Injection-site reactions
- Headache, mood changes
Cautions
- The label states hCG has no proven effect on fat loss; the old “hCG diet” results came from the calorie restriction.
- Raises estradiol along with testosterone: check both on bloodwork.
- A positive pregnancy test is expected while on it.
- Prohibited in tested sports (WADA).
Storage
Unmixed or unopened: Powder at room temperature (20–25 °C).
Mixed or in use: Once mixed, keep it in the fridge (2–8 °C): Novarel says use within 30 days, Pregnyl and the Fresenius Kabi generic allow 60. Do not freeze or shake.
From the Novarel label (shortest of the hCG labels).
Stability once mixed
The labels give 30 to 60 days in the fridge once mixed, depending on the brand.
Heat, shaking, freezing a mixed vial, light and many needle punctures all speed breakdown. Toss it if it turns cloudy, grows specks or changes color.
Reference only, not medical advice. Written for this app from the cited research. Doses marked community-reported are not from trials.