progestin

References

progestin

hormone

Also known as: gestogen

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Last updated

June 17, 2026

Quick Summary

Progestins are a class of synthetic steroid hormones that mimic the effects of progesterone, a natural hormone produced by the ovaries and placenta. Progesterone plays a crucial role in preparing the uterus for pregnancy and maintaining it.1234

Progestins are commonly used in oral contraceptives (birth control pills) to prevent pregnancy. They work by suppressing the release of hormones that trigger ovulation, thus reducing the chance of an egg being released and fertilized. Progestins can also thicken cervical mucus, making it harder for sperm to reach an egg.53

Additionally, antiprogestins, which block the action of progesterone, are used for contraception, labor induction, and treating certain medical conditions.67

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therapeutics
Hormones
Progestins combined with estrogens constitute the oral contraceptives that inhibit ovulation by affecting the hypothalamus and pituitary. Progestin-only pills and injections are also effective contraceptives; they work by forming a thick cervical mucus that is relatively impenetrable to sperm. The
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Progestins combined with estrogens constitute the oral contraceptives that inhibit ovulation by affecting the hypothalamus and pituitary. Progestin-only pills and injections are also effective contraceptives; they work by forming a thick cervical mucus that is relatively impenetrable to sperm. The
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menopause
Estrogen therapy
…given in conjunction with a progestin, and it slightly increases the risk of breast cancer.
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…given in conjunction with a progestin, and it slightly increases the risk of breast cancer.
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oral contraceptive
… (usually ethinyl estradiol) and a progestin (commonly norethindrone). In general, oral contraceptives are taken in a monthly regimen that parallels the menstrual cycle. Protection from pregnancy is often unreliable until the second or third drug cycle, and during this time certain side effects such as nausea, breast tenderness, or bleeding…
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… (usually ethinyl estradiol) and a progestin (commonly norethindrone). In general, oral contraceptives are taken in a monthly regimen that parallels the menstrual cycle. Protection from pregnancy is often unreliable until the second or third drug cycle, and during this time certain side effects such as nausea, breast tenderness, or bleeding…
Read More

hormone
Estrogens
…of gonadal hormones, estrogens and progestins, are secreted in the female mammal. Estrogens are substances that evoke the cyclical onset of heat, or estrus, during which the animal is sexually active and receptive to the male. Estrus in this sense is not found in human females, but estrogens contribute to…
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…of gonadal hormones, estrogens and progestins, are secreted in the female mammal. Estrogens are substances that evoke the cyclical onset of heat, or estrus, during which the animal is sexually active and receptive to the male. Estrus in this sense is not found in human females, but estrogens contribute to…
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steroid hormone
Progestins, the most important of which is progesterone, are the other type of female sex hormone and are named for their role in maintaining pregnancy (pro-gestation). Estrogens and progestins are secreted cyclically during menstruation. During the menstrual cycle, the ruptured ovarian follicle (the corpus
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Progestins, the most important of which is progesterone, are the other type of female sex hormone and are named for their role in maintaining pregnancy (pro-gestation). Estrogens and progestins are secreted cyclically during menstruation. During the menstrual cycle, the ruptured ovarian follicle (the corpus
Read More