Luteinising Hormone Imbalance: Look Out for the Signs

The Biomarker Handbook is a curated series that seeks to provide readers with insights on each biomarker we cover in our blood test packages and its relation to our body.

Luteinising hormone (LH) is vital for both male and female reproductive health. In women, LH has multiple reproductive functions while in men it has one primary role – production of testosterone.

LH is produced in the pituitary gland of your brain together with follicle stimulating hormone (FSH). Levels of both hormones can tell the clinician if any hormonal imbalance is due to sexual gland disorder (ovary and testicle) or cerebral gland disorder (pituitary and hypothalamus).

The Major Functions of LH in Women

Luteinising hormone is responsible for releasing the egg from the ovary during ovulation (known as the LH surge). It also prepares the uterus for pregnancy and has an important role in maintaining healthy pregnancy in the early stage.

A woman’s LH level fluctuates significantly during different stages of her menstrual cycle and during pregnancy. When your doctor takes blood to test your LH level, make sure you know exactly the stage of your menstrual cycle according to the first day of your last menstruation.

Functions of LH in Men

LH is equally important in men as it stimulates the testicular glands to produce testosterone- the male sex hormone which has widespread effects on the body, particularly on the reproductive system. Without this essential hormone, sperm formation is impaired and infertility can occur.

Functions of LH in Children

Right after birth, the levels of both LH and FSH are high. Studies have found that male newborn babies have higher levels of this hormone. These levels then fall until puberty is reached. LH and FSH are responsible for the production of sex hormones that regulate secondary sexual characteristics in boys and girls. Any abnormal pubertal or childhood development in sexual characteristics should include a hormonal testing with LH levels.

The LH Blood Test

The test can be ordered for a number of reasons, but it is most commonly ordered when conception is difficult and there is a suspicion of infertility. The LH test is ordered when:

  • there is a suspicion of infertility
  • puberty is late or early
  • periods are frequently irregular or even absent for months
  • there are signs of low testosterone levels in a man such as decreased libido
  • there is a pituitary disease (for example a tumor)

Imbalances in LH levels

Elevated serum levels of LH are seen in menopausal women as their ovaries cease to function.

In women, high LH levels when associated with high FSH levels, are typically seen in women with primary ovarian problems (from chromosomal abnormality, exposure to radiation, chemotherapy, autoimmune disease, polycystic ovaries, thyroid disease, adrenal disease, and ovarian tumor).

In women, low serum LH levels when associated with low FSH levels, are typically caused by pituitary or hypothalamic disorders. When there is a decrease in LH in the blood, periods may be completely absent. Other symptoms of decreased LH levels in the blood are a decreased sexual drive or libido, and increased fatigue and lethargy.

Likewise, in men, high LH and FSH levels are seen in testicular diseases, while low levels of both hormones are associated with pituitary or hypothalamic disorders.

Certain drugs can also affect the level of LH in the body. These drugs include birth control pills, hormone replacement therapies, anticonvulsants and digoxin.


LH is needed by our bodies for healthy reproductive function. If you suspect any of the symptoms indicating an imbalance, it is important to talk to your doctor and get a blood test done.

If you want to find out more about LH and why its important for the body, take a look at our lifestyle article here!

Interested in other biomarkers? Check out the rest of The Biomarker Handbook.

For more information, drop us a message and we will get back to you.

The post Luteinising Hormone Imbalance: Look Out for the Signs appeared first on BioMark.