They are the hormone inhibin A, alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and a type of estrogen (unconjugated estriol, or uE3). It checks the levels of four substances in a pregnant woman's blood. In most cases, this test is done between 15 and 22 weeks of pregnancy. This is the major source of estrogen in women who have gone through menopause.įor pregnant women, the level of estriol in the blood is used in a serum quad screening test. Small amounts of estrone are made throughout the body in most tissues, especially fat and muscle. In men, small amounts of estrogens are made by the adrenal glands and testicles. Small amounts are also made by the adrenal glands. In women, estrogens are made mainly in the ovaries and in the placenta during pregnancy. Estrogens are responsible for female sexual development and function, such as breast development and the menstrual cycle. It also may be measured in men or women who might have cancer of the ovaries, testicles, or adrenal glands.īoth men and women make estrogen hormones.

It's done to find out their estrogen levels. Estrone may be measured in women who have gone through menopause.Estriol can be found as early as the 9th week of pregnancy. This is the tissue that links the fetus to the mother. Estriol is produced in large amounts by the placenta. Estriol levels are most often measured only during pregnancy.

After menopause, it drops to a very low but constant level. The amount of estradiol in a woman's blood varies throughout her menstrual cycle.

Estradiol is the most common type of estrogen measured for nonpregnant women.

It measures estradiol, estriol, and estrone. An estrogen test measures the level of the most important estrogen hormones in a blood or urine sample.

Adrenal gland estrogen production