Oestro­gens

Oestrogens are the female hormones of the menstrual cycle.
They are produced mainly by the developing eggs in the ovary and have a range of effects throughout the body. To a lesser extent, they are formed in the adrenal cortex and in fat cells.
Men also produce oestrogens, to a lesser extent, in the testes.

How oestro­gens affect the female menstrual cycle

• They make the lining of the uterus grow (formation of new blood vessels, thickening of the lining, growth of the glands).
• In the middle of the cycle, they make the cervical mucus more fluid.

How oestro­gens affect the body

(mainly during puberty)

• They bring about the development of the female genital organs and the secondary female sex characteristics, that is, they promote the growth of the uterus, the fallopian tubes, the breasts and the vagina.
• They increase fat storage and give the body its typical female shape.
• During puberty, together with androgens, they lead to the closure of the growth plates and bring growth in height to an end.

Effects on metab­o­lism and blood vessels

• Oestrogens inhibit the growth and sebum production of the sebaceous glands.
• They influence metabolism in the liver (increased formation of HDL and a fall in LDL).
• They increase the formation of clotting factors.
• They lower peripheral vascular resistance.
• At higher doses, they make the body retain sodium and water.
• They prevent the breakdown of bone.
• They reduce the action of androgens and glucocorticoids.