Estriol

Estriol is one of the three main estrogens produced by the human body, the others being estradiol and estrone. It is a steroid hormone and plays a crucial role in the female reproductive system. Estriol is considered a weak estrogen compared to estradiol and estrone.

Synthesis

Estriol is primarily synthesized in the liver and placenta. During pregnancy, estriol is produced in significant amounts by the placenta. The synthesis of estriol involves the conversion of androstenedione and testosterone into estriol through a series of enzymatic reactions. The steroidogenesis pathway illustrates the conversion of cholesterol into various steroid hormones, including estriol.

Function

Estriol has several functions in the body, particularly during pregnancy. It helps maintain the uterine lining and supports the development of the fetus. Estriol levels increase significantly during pregnancy and are often used as a marker in prenatal screening tests to assess fetal health and development.

Clinical Significance

Estriol is used in various clinical applications, particularly in hormone replacement therapy (HRT) for menopausal women. Due to its weaker estrogenic activity, it is considered to have a lower risk of causing breast cancer compared to other estrogens. Estriol is also used in the management of vaginal atrophy and other menopausal symptoms.

Related Pages

• Estrogen
• Estradiol
• Estrone
• Steroidogenesis
• Hormone replacement therapy