Pathology Handbook

Luteinising Hormone (LH)

Synonyms

Luteinising Hormone (LH)

Clinical Indications

LH is an anterior pituitary hormones which regulates male and female gonadal function. Measurement of LH can be useful in suspected disorders of gonadal function.

Request Form

Request on ICE

Availability

On request

Specific Criteria

Investigation of suspected hypothalamic, pituitary or gonadal dysfunction.

If the sample is for ?menopause ONLY an FSH is required

Patient Preparation

LH is suppressed in patients taking the combined oral contraceptive pill and there is no point in measuring gonadotrophin levels under these circumstances

Turnaround Time

Same Day (Monday to Friday)

Specimen

Serum

Volume

2 ml

Container

Vacutainer gold top

Collection

If patient is having menstrual cycles, collect between days 1 to 5 of cycle

Causes for Rejection

Unlabelled or incorrectly labelled sample

Reference Range

In women in the early follicular phase (days 1-5 of cycle) and in men: 1-10 U/L

Levels in women rise at mid-cycle and are difficult to interpret at this time.

Interpretation

Low LH/FSH: pituitary / hypothalamic disease.
High gonadotrophins: primary gonadal failure (LH and FSH), azoospermia / ovulatory failure (FSH), polycystic ovary syndrome (LH>FSH).
Towards the menopause, FSH tends to rise before LH, although both show considerable variation. After the menopause, levels of both FSH and LH are greatly elevated (greater than 28 U/L).