Estrogens (follicular hormones)
The most important estrogens are estradiol, estrone and estriol.
In puberty estrogens already play an important role in 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.). The increased production of estrogens during puberty leads to gradual closure of the growth plates in the long bones (epiphyses) and thus to termination of longitudinal growth.
In the sexually mature woman estrogens, together with progesterone, control the menstrual cycle and pregnancy. But the estrogens also have important
actions outside the reproductive system. For example, they are important for maintaining healthy bone and have a positive influence on general wellbeing, mood and libido (sexual desire). The oiliness of the skin and the blood supply to the mucous membranes is also estrogen dependent.
Progestins (progestational hormones)
The term progestins is a collective term for the natural hormone progesterone and synthetic hormones with progesterone-like action. Progesterone, the most potent progestin produced by the body, regulates the menstrual cycle in conjunction with the estrogens. It is especially responsible for maintaining pregnancy.
Progesterone also has actions over and above the direct regulation of reproduction. Progesterone influences body temperature, for example. This effect is utilized in the temperature method of contraception.
In some respects progesterone has the opposite action to the estrogens. For example, while estrogen stimulates the growth of certain tissues in the female genital organs (e.g. the lining of the womb), progesterone reverses the actions of the estrogens shortly afterwards and leads to differentiation of the target tissue.
Androgens, the male sex hormones
Women also produce small amounts of
male sex hormones.
The male sex hormones produced by women serve mainly as chemical intermediates in the production of estrogens. Increased production of androgens in women can lead to disorders such as
acne or
hirsutism.
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