A progestin is a so-called corpus luteum hormone. Along with estrogens, progestins belong to the female sex hormones, they are so-called steroid hormones.
What is progestin?
Progestins are so-called steroids, the basic structure of which is pregnane. Progesterone, pregnanediol and pregnenolone are the most important representatives of progestins. The natural progestin is a corpus luteum hormone that is produced by the female body itself. There are also synthetic progestins, which are also called progestagens or progestins. Progestin is a type of chemical derivative of the body’s own hormone progesterone, which is responsible for regulating ovulation and preparing the lining of the uterus for implantation of an egg.
Medical and health functions, roles, and meanings.
Progestins are usually used to prevent pregnancy. They are usually used here as a combination with an estrogen. These include, for example, dienogest, lynestrenol, and norethisterone. Progestogens can also be used alone to prevent pregnancy. However, the individual substances allow only slight control of the monthly cycle and are therefore not as safe as the combination with estrogens. Progestogens that can be used alone include desogestrel and levonorgestrel. Medroxyprogesterone acetate and etonogestrel are also among the progestins that can be used alone. Desogestrel and levornogestrel are often used as mini-pills. The minipill has a lower hormonal impact on women, so it is recommended above all for nursing mothers. The effect of this minipill is generally short-lived, which is why it is particularly important to take it at the same time every day if possible. Medroxyprogesterone is administered in the form of a depot injection. This is injected into the muscles, where it forms a depot from which the active substance is released into the blood over a period of several weeks or even months. Implants with etonogestrel and intrauterine devices with levornogestrel are also suitable for long-term contraception. Levornogestrel is known in high-dose form as the “morning-after pill”, which can be used to prevent pregnancy. However, this is not a contraceptive, but rather a type of emergency medication consisting of two tablets that must be taken either simultaneously or 12 hours apart. The intake must be taken thereby within 72 hours, better still within 12 to 24 hours after sexual intercourse, so that an effect is achieved.
Effect
The mode of action of chemical progestins is modeled on that of the natural progestin progesterone. Along with estrogens, progesterone is one of the female sex hormones. It is produced in rhythmically changing quantities in the ovaries, with the effects of estrogens and progesterone interlocking. The estrogens cause the uterine lining to grow, while the progesterone subsequently prepares it to embed the fertilized egg. Once an egg has been formed and released in the ovaries by the action of the estrogen, the progesterone helps to prevent further ovulation and egg maturation, and thus a twin pregnancy. After successful fertilization, progesterone takes on the task of solidifying the vaginal mucus and cervical mucus so that no more sperm can reach the uterus. It also ensures that pregnancy is maintained after implantation. If neither fertilization nor pregnancy has occurred, the progesterone level drops again. A so-called withdrawal bleeding occurs, during which the built-up tissue of the endometrium is shed. The chemical progestins are usually used to prevent pregnancy, so the mode of action is somewhat different here. In principle, progestins mimic the effects of progesterone. They prevent the egg from maturing, they solidify cervical mucus and vaginal mucus, and they also partially suppress ovulation.
Intake
Progestins taken as a single agent are used continuously. There is no break from taking them for a week, and thus there is no need for regular withdrawal bleeding.The previously accustomed bleeding pattern changes – either the bleeding is irregular or disappears completely. In almost every woman, bleeding decreases after a few months of use and only occurs very rarely. If progestins are used as the “morning-after pill,” they inhibit ovulation and thus also the fertilization of a mature egg. They also prevent the implantation of a fertilized egg in the uterus. However, if the egg has already implanted, the “morning-after pill” is not suitable for abortion.
Diseases, ailments and disorders
When progestins are taken in combination with estrogens, they have an anticancer effect in menopausal symptoms. Because estrogens promote the buildup of the endometrium, which can lead to the development of cancer cells in some circumstances, progestins are added so that withdrawal bleeding occurs, during which the endometrium is shed again. If progestins are combined throughout, this usually leads to an underdeveloped endometrium in the long term and thus to only a low risk of cancer. If a woman develops endometriosis, progestins can help to break down the endometrium. This can prevent symptoms caused by inflammation and bleeding. Progestins can generally fulfill the tasks of natural progesterone. A lack of progesterone often leads to menstrual disorders, which can then often result in an unwanted abortion. In this case, progestins are used to compensate for the lack of progesterone. It is also suspected that progestins can act against cancer cells that form estrogen receptors. However, the effect on cancer cell growth is not yet fully understood.
