Oestrogen is one of a group of steroid hormones that control female sexual development, both promoting the development and function of the female sex organs, and female secondard sexual characteristics - including breast development, for example.
Although oestrogens are synthesized mainly by the ovaries, some small quantities of oestrogen are also produced by the adrenal cortex, the testes, and the placenta. (Oestrogen is present in males but excessive production of oestrogen in men can lead to feminization.)
The actions of the hormone oestrogen include:
- Control of female sexual development;
- Promotion of the growth of female secondary sexual characteristics at puberty;
- Stimulation of egg (ovum) production;
- Preparation of the lining of the uterus for pregnancy;
- In conjunction with progesterone, regulation of the growth and functioning of sex organs for sexual reproduction;
- Oestrogens are used in female oral contraceptives, to inhibit the production of ova.
Note that pharmaceutical products vary widely and should only be used as directed by qualified professionals.
See also: What is a Hormone ?
For further general information including the locations of the endocrine glands, see the Endocrine Glands of the Human Body.
- Introduction to the Endocrine System
- What is a hormone ?
- Water Soluble Hormones vs Fat Soluble Hormones
- Triggers for Hormone Release
- Hormone Regulation Feedback Mechanism
- Major Glands of the Endocrine System
- The Pituitary Gland
- The Adrenal Glands
- Non-endocrine tissues that release hormones
- Conditions of the Endocrine System