The LH test measures the level of luteinizing hormone (LH) in the blood. LH is produced by the pituitary gland and plays a crucial role in sexual development and functioning. In women, LH helps control the menstrual cycle and triggers the release of an egg from the ovary, known as ovulation. In men, LH stimulates the testicles to produce testosterone, which is essential for sperm production. In children, LH levels rise before the start of puberty. The test is used to diagnose infertility, menstrual difficulties, low sex drive, and early or delayed puberty. It is also used to evaluate ovulation, menopause, and pituitary disorders that affect LH production
. The LH test is performed by analyzing the levels of luteinizing hormone in the blood or urine. In women, the test may need to be done on a specific day of the menstrual cycle to evaluate ovulation. Normal LH levels vary depending on sex and age. For women, normal results are typically 5-25 international units per liter (IU/L) before menopause and 14.2-52.3 IU/L after menopause. Abnormal results in women may indicate issues such as infertility, hormonal imbalances, or menopause. In men, high levels of LH in the blood can indicate problems with the testicles
. The LH test is often used in conjunction with other tests, such as follicle- stimulating hormone (FSH), testosterone, estradiol, and progesterone, to diagnose infertility, pituitary disorders, and conditions affecting the function of the ovaries or testicles. Additionally, LH tests can be used to investigate irregular periods, evaluate LH levels during the menstrual cycle, and diagnose delayed or precocious puberty in children
