What is this test?
LH is a pituitary hormone that is involved in ovulation, the menstrual cycle and the production of sex hormones in women and men.
Why might it be ordered?
- For irregular menstrual cycles, difficulty conceiving or suspected ovulation problems.
- To evaluate ovarian, testicular, or pituitary function along with other hormones.
What sample is needed?
A healthcare professional collects a venous blood sample. Depending on the method, the laboratory uses serum or plasma.
How should you prepare?
For women, the day of the cycle may matter. Confirm the collection day and report any hormone treatment. Tell the laboratory about all medicines, hormone treatments, vitamins and supplements you take. Do not stop or change treatment unless your clinician tells you to. Follow any instructions about fasting and the time of collection.
How should you understand the result?
The result is interpreted according to sex, age and cycle phase, together with FSH, estradiol, testosterone or other requested hormones. Your result is interpreted using the reference interval on the laboratory report and in the context of your symptoms, medical history and other test findings.
Sources and editorial status
This patient-facing text is an editorial draft. It should be approved by a laboratory physician before official publication.