Luteinizing Hormone

also known as LH

NORMAL_RANGE
1.7 – 8.6 mIU/mL
UNIT
mIU/mL

/WHAT_IT_IS

Luteinizing hormone (LH) is released by the pituitary gland and signals the testes to produce testosterone. On TRT it falls to near-zero because exogenous testosterone shuts down the HPTA.

/NORMAL_RANGE

Adult male reference: 1.7–8.6 mIU/mL.

What does high LH mean?

  • +Primary hypogonadism (testicular failure) — testes can't respond, pituitary keeps shouting.
  • +Pituitary tumor (rare).

What does low LH mean?

  • +Exogenous testosterone (TRT, AAS) — the most common cause.
  • +Secondary hypogonadism (pituitary or hypothalamic problem).
  • +Hyperprolactinemia.

/ON_TRT

LH almost always reads <1.0 mIU/mL on TRT — that's expected and not a problem in itself. Men trying to preserve fertility add hCG (which mimics LH) to maintain intratesticular testosterone production. If you're planning to come off TRT, monitoring LH recovery is part of the restart protocol.

/RELATED

FAQ

/01Will LH come back after stopping TRT?+

For most men, yes — but it can take 3–12 months, and a small percentage don't fully recover. The longer you've been on TRT and the higher the dose, the longer recovery typically takes. Restart protocols often use clomiphene or hCG to accelerate recovery.

/02What does luteinizing hormone do in men?+

LH is released by the pituitary gland and signals the Leydig cells in the testes to produce testosterone. It's the main upstream driver of your natural testosterone output. The adult male reference range is roughly 1.7–8.6 IU/L.

/03What is the relationship between LH and testosterone?+

The brain and pituitary release LH, which tells the testes how much testosterone to make; rising testosterone then feeds back to dial LH down, keeping levels balanced — the HPG axis. When testosterone is low from a testicular problem, LH usually runs high as the pituitary tries to compensate. When it's low from a pituitary or hypothalamic problem, LH is low or normal alongside low testosterone.

/04Why is LH near zero on TRT?+

Exogenous testosterone tells the brain that plenty of hormone is present, so the pituitary stops releasing LH through negative feedback. LH typically reads under 1.0 IU/L on TRT, which is expected rather than a problem. Because the testes lose their LH signal, men who want to preserve fertility or testicular size often add hCG, which mimics LH.

/TRACK_THIS

Track LH in the app.

Upload your lab PDF — My TRT App extracts every marker with Gemini Vision. Charts, trends, and TRT-aware insights. Free on iOS and Android.

Last reviewed: 2026-09-02 · My TRT App does not provide medical advice. Always consult your physician.