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Are you a woman aged 45 or over? Then an LH test is usually not needed. At that age, a high LH value is usually a sign of the normal menopause.[1]
On this page you can read what LH is, what the guidelines say about a value that is too low or too high, what affects your value and which other values are best read alongside it.
Also known as: luteinising hormone, lutropin, ICSH (interstitial cell stimulating hormone). At the lab: LH.
LH stands for luteinising hormone. A hormone is a chemical messenger in your blood. It controls what certain cells or organs do. LH is usually measured in your blood, sometimes in urine.[1]
LH is made by the pituitary gland, a small gland at the base of your brain. The hypothalamus, a part of your brain, tells the pituitary gland how much LH to make.[1]
Your ovaries or testicles make sex hormones. Their levels tell the hypothalamus and the pituitary gland when to start and stop making LH.[1]
An LH test helps find a condition that causes too much or too little LH. How the test is used depends on your sex, your age and your symptoms.[1]
In women, the test can help if getting pregnant has not worked after 12 months of trying, if periods are irregular or have stopped, or to see whether the menopause has begun.[1]
In men, the test can help find the cause of a low sperm count, low testosterone or a reduced sex drive. It can also help if your partner has not become pregnant after 12 months of trying.[1]
If your healthcare provider suspects a condition of the pituitary gland, an LH test can help. Such a condition can affect your fertility and your sex drive. It can also cause tiredness, weakness, a reduced appetite and a drop in your body weight.[1]
Labplusarts, the lab BioProfile works with, uses a reference value of 0.6 to 12.1 U/L for LH. The lab calls a value within these limits normal.[2]
| Situation | What it can mean | Who it is for |
|---|---|---|
| High LH value from age 45[1] | Usually a sign of the normal menopause | Women aged 45 or older |
| LH rises a few weeks after the period[1] | Usually a normal ovulation | Women who have periods |
| Signs of sexual development before the age of 8[1] | Early puberty; an LH test can help find the cause | Girls |
| Signs of sexual development before the age of 9[1] | Early puberty; an LH test can help find the cause | Boys |
| No signs of sexual development by age 13[1] | Late puberty; an LH test can help find the cause | Girls |
| No signs of sexual development by age 14[1] | Late puberty; an LH test can help find the cause | Boys |
Source: MedlinePlus, U.S. National Library of Medicine. Situations in which LH tells you something, in adults and children.[1]
In young children, LH is normally low. In adults, too little LH can point to a problem in the pituitary gland, the hypothalamus, or the ovaries or testicles. Your healthcare provider reads the result alongside your sex, age, symptoms and other hormone values, especially FSH.[1]
A rise in LH a few weeks after your period usually points to normal ovulation. From the age of 45, a high value is usually a sign of the normal menopause. Otherwise, too much LH can point to a problem in the pituitary gland, the hypothalamus, or the ovaries or testicles.[1]
BioProfile is working on its own zones for each value, from risk to optimal. A doctor reviews those zones before they appear in your result.
If you have periods, your LH changes over the course of the month. Just before ovulation, LH rises quickly. That is why you sometimes need to have the test at a specific point in your cycle.[1]
Sometimes you need to stop certain medicines or supplements before the test. Tell your healthcare provider everything you take. Do not stop taking prescribed medicines unless your healthcare provider tells you to.[1]
In young children, LH is low. It starts to rise slowly in the years before puberty, usually between the ages of six and eight. When puberty begins, LH rises further, along with other hormones.[1]
Around the menopause, your ovaries release fewer eggs. Your body then makes more hormones to still bring about ovulation. This is why LH is often high.[1]
LH is included in BioProfile 121 and 150.[3]
The BioProfile editorial team wrote this page on 10 October 2026 from the sources below, which we read on 10 October 2026. Every number on this page appears in one of those sources, with that source's number next to it. An expert has yet to check this page; after that check, the expert's name and the date of the check will appear at the top. This page offers explanation, not a diagnosis. Discuss a value outside the range with your GP.
