Luteinizing Hormone (LH) Testing

What is Luteinizing Hormone (LH) Testing?

A Luteinizing Hormone (LH) test is used to measure the amount of luteinizing hormone, which is produced by the pituitary gland, in a patient’s blood or urine. In female patients, the hormone plays a part in regulating the menstrual cycle as well as egg production, otherwise known as ovulation, and the levels vary depending on what phase of the menstrual cycle a woman is currently in. About midway through a woman’s cycle her levels of LH rise significantly and is referred to as an LH surge – the most fertile period of the menstrual cycle. In male patients, luteinizing hormone (LH) plays a role in the production of testosterone, which is critical to the formation of sperm.

Who May Need a Luteinizing Hormone (LH) Test?

Luteinizing Hormone (LH) tests are often performed as part of a workup to discover the cause of a couple’s or patient’s infertility, determining a woman’s egg supply (ovarian reserve), when a woman is ovulating, as well as a man’s sperm count. It can also be used to evaluate menstrual issues occurring in female patients, such as irregular or absent menstrual periods for example, which can be useful in determining if a woman has gone through menopause. In younger patients, the LH test is used to determine if a child is undergoing early puberty, and also to assess why sexual features or organs are underdeveloped for their age.

What Should I Expect from My Luteinizing Hormone (LH) Test?

Most Luteinizing Hormone (LH) tests begin by drawing a sample of blood from a patient in order for it to be analyzed by a medical laboratory. At times, more than one sample may be taken in order to provide an accurate indication of a patient’s LH levels. Results from a Luteinizing Hormone (LH) test are dependent upon a person’s age as well as what stage of sexual development they are in, and are also affected by what phase a female patient is in with regards to her menstrual cycle. A significant deviation from the normal range may require further evaluation by your physician.