Estrogens and progesterone are the female sex hormones. They are produced chiefly by the ovaries, during pregnancy also by the placenta.

The sex hormones are carried through the body with the bloodstream and are thus able to reach all organs.

Estrogens cause the maturation and development of the typical female sex characteristics (development of the female breast, typical fat distribution with increased fat deposits around the hips and thighs, body hair distribution etc.).

Estrogens and progesterone together regulate the menstrual cycle and are indispensable for the occurrence and maintenance of pregnancy.

In addition, estrogens and progesterone have many other actions which are important for maintaining health and wellbeing.

But what ensures that the body always produces exactly the amounts of hormones required? Production of the sex hormones is controlled by the hypothalamus (a region in the forebrain) and the pituitary gland.