Hormone panel
LH
Also called Luteinising hormone · measured in IU/L
What it measures
The pituitary hormone that signals the testes to produce testosterone.
Why it is tracked
LH distinguishes primary from secondary hypogonadism. A low testosterone with high LH points to the testes; a low testosterone with low or normal LH points upstream to the pituitary or hypothalamus. That distinction changes what treatment is appropriate.
What a provider considers
- Suppressed by exogenous testosterone
- Central to deciding whether enclomiphene is a realistic option
- Measured alongside FSH
Reference ranges vary between laboratories and a single result rarely means much on its own. Interpretation depends on your symptoms, your other markers and the trend over time — which is what your provider reviews.