Basically, LH stands for luteinizing hormone and it is produced by the pituitary gland. In women, the LH is responsible for releasing an egg into the fallopian tube. In men, the LH is responsible for the production of testosterone.

Your doctor might order blood tests to measure luteinizing hormone levels in several circumstances:

• Infertility issues or difficulty conceiving a child

• Irregular menstrual period particularly in teen girls

• To evaluate pituitary function, diagnose pituitary disorders or diseases involving the ovaries or testes

• To determine or confirm the onset of menopause

• Precocious or late onset of puberty

Blood tests for LH levels in women usually also include FSH (follicle stimulating hormone).

How LH Works

Your menstrual cycle consists of three phases. Phase one, the follicular phase, begins on the first full day of menstrual bleeding. Phase two, is the ovulatory phase and immediately follows the end of a woman’s period.

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