Luteinizing Hormone(lh)

Male: 1.24 - 7.8 mIU/ml

Female:

Follicular phase: 2.4 - 12.6 mIU/ml

Ovulation phase: 14.0 - 95.6 mIU/ml

Luteal phase: 1.0 - 11.4 mIU/ml

Post menopause:  25.8 - 135.0 mIU/ml

Pregnant: < 0.5 mIU/ml

Other Names: LH, Lutropin

A LH test is a blood test that measures the level of Luteinizing Hormone in the blood. It helps to evaluate fertility issues or the health of reproductive organs (ovaries or testicles). In women, it helps whether you have ovulated (released an egg from the ovary) or to evaluate pituitary function. In children, to evaluate early or delayed puberty

Luteinizing Hormone, like the FSH is produced by the pituitary gland and is responsible for the control and regulation of the reproductive system. The amount of LH in the body can help identify reproductive problems, if any.

The LH test is primarily used to determine the cause of infertility in women. Along with FSH, the LH is responsible for the process called Ovulation. FSH stimulates the ovarian follicle and causes an egg to grow. FSH also triggers the production of estrogen and when the levels of estrogen rises, the pituitary gland stops production of FSH and releases more LH. The LH causes the egg to be released from the ovary and this process is called as the Ovulation.  Further to ovulation, progesterone levels rise and this is important to sustain pregnancy. When pregnancy does not occur, the progesterone levels drop and ultimately it leads to menstruation. Therefore, measuring LH levels gives a doctor an understanding of fertility in a woman.

• Puberty: LH levels are also measured when the onset of puberty is either early or delayed both in boys and girls
• Fertility: LH levels are directly related to the supply of eggs in a woman and a man’s sperm count.
• Pregnancy: A higher LH level is the best time to conceive and can help couples who are trying to plan their intercourse accordingly.
• Benign tumors could lead to low sex drive in men and can cause breasts to produce milk in women even when they are not lactating or pregnant. A LH test can help determine the underlying cause.
• Sexual dysfunction and low sex drive in women could be due to low LH levels as LH levels regulate the production of testosterone

Interpretation:

Male:

• Levels may be low in case of infertility, low sex drive, lack of erection and low sperm count
• In Children, the levels may be elevated in case an injury or inflammation to the central nervous system is suspected. An LH test may also be ordered if there is either an early or a delayed onset to puberty.

Female:

• The LH test is almost always ordered along with an FSH test in women. Elevated levels of LH and FSH are seen in women for a number of reasons.
• When a doctor suspects some kind of development disorder, increased levels are seen when there is a failure to develop ovaries, Turner syndrome (chromosomal disorder), a deficiency in steroid production by the ovaries or some kind of cysts, injury or damage to the ovary.

Higher levels of LH are also seen in PCOS, adrenal or thyroid disease