Progesterone

Progesterone is a steroid hormone belonging to the group of progestin hormones. Although a small amount is also produced in humans (Leydig's testicular cells), progesterone is a typical female hormone.

In women of fertile age it is secreted by the corpus luteum and the placenta. The corpus luteum is formed following ovulation, when the follicle releases the egg cell contained in it and is replaced by a cluster of cells with a characteristic yellow color. The corpus luteum - under the stimulus of hypothalamic hormones (LH) - begins to produce progesterone, with the aim of preparing the body for pregnancy.

If fertilization does not occur, the regression of the corpus luteum begins after a few days in the ovary. The reduction of progesterone levels leads to the exfoliation of the uterine mucosa (endometrium), therefore to menstruation.

In case of pregnancy the placenta starts to produce progesterone which is associated with that synthesized by the gravidic corpus luteum.

Progesterone of natural origin or its synthetic derivatives are used in various fields ranging from birth control pills to hormone replacement therapy, where natural micronized progesterone is used in combination with estrogens to lower the risk of developing a carcinogenic endometrial or mammary disease.

A CURIOSITY: progesterone is a thermogenic hormone, that is, it favors the increase in body temperature (around 0.5-1 degree). During the post-ovulatory phase (more or less from the 16th to the 26th day) women therefore burn much more calories than on the other days of the cycle (between 10 and 15% more).