Luteinizing Hormone (LH) Levels Test
Reviewed
This test measures the level of luteinizing hormone (LH) in your blood. LH plays an important role in sexual development and fertility. The test is used to help diagnose conditions that cause too much or too little LH, such as infertility, menstrual irregularities, pituitary disorders, and early or delayed puberty in children.
Preparation and collection
You may need to stop taking certain medicines or supplements before your test. Tell your provider everything you take. If you have menstrual periods, you may need to have your test at a specific time during your menstrual cycle.
Understanding this test
Use the reference interval and units printed by the laboratory that performed the test. A result outside that interval is not a diagnosis by itself, and a result inside it does not rule out every condition. Your symptoms, history, medicines, timing, and related tests can change what the result means.
- LH levels naturally vary throughout the menstrual cycle in women who menstruate.
- Results must be interpreted alongside other hormone tests (FSH, estrogen, testosterone, progesterone) and your medical history.
- At-home urine ovulation tests are screening tools and do not diagnose any condition.
What to do next
Your healthcare provider will explain what your LH test results mean in the context of your sex, age, symptoms, medical history, and other hormone test results.
Evidence source
U.S. National Library of Medicine: Luteinizing Hormone (LH) Levels Test