LH (Leutinizing Hormone) Test

An LH test is performed to identify problems associated with fertility. It is done in the following cases:  

• Early or delayed onset of puberty
• Impotence or low sex drive in men
• Irregular periods
• Difficulty in getting pregnant
• Menopause

No special preparations are needed for this test. However, your doctor will ask you to temporarily stop some medicines, such as birth control pills and testosterone, as it may interfere with test results. Also, it is important to inform the doctor about all the medicines, including vitamins, herb and supplements, which you are taking.

In case of women of childbearing age, LH test is done on a specific day of the menstrual cycle. Inform the doctor about any previous exposure to the radioisotope in tests, such as nuclear medicine.

Wearing a small sleeve t-shirt or shirt can help in the easy withdrawal of blood from arm.

A blood sample is collected from a vein in the arm using a needle. Moderate pain is felt when the needle is inserted into the vein. Some people feel only a stinging or prick. A slight bruise or throbbing may be observed at the site of injection, which disappears quickly. The site of injection may be sore for a while.

Some of the risks associated with this test include a light-headed feeling, excessive bleeding, accumulation of blood or infection at the site of injection.

Variations in test results may be seen based on the age, sex, medical history, method of testing and other factors. 

Normal results: The normal ranges are given below:

Abnormal results:

In women, abnormally high LH levels during the non-ovulatory phase of the menstrual cycle indicate menopause or polycystic ovary syndrome. Low LH levels in women indicate anorexia, malnutrition or stress. A pituitary gland disorder can cause both low and high LH levels. 

In men, high LH levels with low testosterone levels may indicate that the testicles are not responsive to the signals given by LH for producing testosterone. Abnormally low levels of LH in men indicates that the pituitary gland is unable to produce sufficient LH, and hence low levels of testosterone are also be observed.

Higher than normal levels of LH in women can be due to the following:

• Absence of ovulation in women of childbearing age
• During or after menopause
• A rare genetic condition called Turner’s syndrome 
• Imbalance in sex hormones in conditions such as polycystic ovary syndrome
• Little or no production of hormones by the ovaries (Read more: Female hormones imbalance)

Higher than normal levels of LH in men can be due to the following:

• Absence of testes or non-functional testes
• Overactive endocrine glands or tumour-producing endocrine glands
• Genetic conditions, such as Klinefelter’s syndrome

Abnormally lower LH levels are usually due to reduced production by the pituitary gland.

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational perspective and is in no way a substitute for medical advice from a qualified doctor.