Hormones affect key functions in the female body, and if one hormone goes out of balance, it is a matter of time as to when and how it affects others. When and what tests should be done to determine the level of hormones ===in the body? ## Estrogens The main female hormone, and in fact a group of hormones — (estradiol, estriol, and estrone), is responsible for regulating the reproductive system and the menstrual cycle. Mood swings, PMS, discomfort during menstruation may indicate a high level of estrogen. Vaginal dryness, headaches, depression are signs of low estrogen levels. Tests for estradiol and estrone are done to identify the causes of menstrual irregularities, early or late puberty in girls, infertility, and to detect tumors. ## Progesterone The ovaries, adrenal glands, and placenta (in pregnant women) produce progesterone. This hormone helps stabilize the menstrual cycle and prepares the body for pregnancy. The level rises during ovulation and rises sharply during pregnancy. Low progesterone levels can lead to irregular periods, difficulty in conceiving, and a high risk of complications during pregnancy. If you have problems with conception, a progesterone test will show if you are ovulating normally. If you're already pregnant, your progesterone levels indicate a risk of miscarriage or other complications. ## Testosterone Yes, this "male hormone" is also present in the female body. It is responsible for sexual drive, menstrual regulation, and bone and muscle strength. Increased testosterone levels in women can cause acne, thinning scalp hair, excess body and facial hair growth, irregular menstruation, and decreased breast size. With polycystic ovary syndrome (a hormonal disorder, one of the causes of female infertility), testosterone levels are often elevated. Lack of testosterone leads to decreased libido, weight gain, body flabbiness, constant fatigue, and depression. ## Prolactin Prolactin is produced by the pituitary gland. In women, this hormone can interfere with fertility because it makes it difficult for the ovaries to produce estrogen. Prolactin causes breast growth and milk production during pregnancy and after childbirth. Excess can lead to unwanted lactation, menstrual irregularities, and sexual problems. Lack can lead to an insufficient amount of milk in a nursing mother. A blood test for prolactin is taken along with other tests to determine the function of the pituitary gland. A prolactin test is needed to diagnose prolactinoma (a type of pituitary tumor). It is recommended for infertility or irregular menstruation. ## Thyroid-stimulating hormone (TSH) Another pituitary hormone regulates the activity of the thyroid gland. With excess (hyperthyroidism), there is anxiety, weight loss, trembling hands, increased heart rate, swelling, and sleep problems. If the amount of TSH is low, hypothyroidism may occur. Irregular menstruation, weight gain, poor tolerance to low temperatures, fatigue, hair loss, constipation can indicate an underactive thyroid gland. To diagnose problems linked to the thyroid gland in time, a TSH test is performed, as well as a blood test. The test can also detect thyroid disease before any symptoms appear.