Hormonal contraception in the context of "Estradiol (medication)"

Injectable birth control is a form of hormonal contraception and may refer to:

• Progestogen-only injectable birth control
• Combined injectable birth control

Estrogen-only injectable birth control, for instance estradiol undecylate, has also been studied, but has not been marketed.

Combined hormonal contraception (CHC), or combined birth control, is a form of hormonal contraception which combines both an estrogen and a progestogen in varying formulations.

The different types available include the pill, the patch and the vaginal ring, which are all widely available, and an injection, which is available in only some countries. They work by mainly suppressing luteinising hormone (LH) and follicle-stimulating hormone (FSH) and in turn preventing ovulation.

A progestogen, also referred to as a progestagen, gestagen, or gestogen, is a type of medication which produces effects similar to those of the natural female sex hormone progesterone in the body. A progestin is a synthetic progestogen. Progestogens are used most commonly in hormonal birth control and menopausal hormone therapy. They can also be used in the treatment of gynecological conditions, to support fertility and pregnancy, to lower sex hormone levels for various purposes, and for other indications. Progestogens are used alone or in combination with estrogens. They are available in a wide variety of formulations and for use by many different routes of administration. Examples of progestogens include natural or bioidentical progesterone as well as progestins such as medroxyprogesterone acetate and norethisterone.

Side effects of progestogens include menstrual irregularities, headaches, nausea, breast tenderness, mood changes, acne, increased hair growth, and changes in liver protein production among others. Other side effects of progestogens may include an increased risk of breast cancer, cardiovascular disease, and blood clots. At high doses, progestogens can cause low sex hormone levels and associated side effects like sexual dysfunction and an increased risk of bone fractures.

An estrogen (E) is a type of medication which is used most commonly in hormonal birth control and menopausal hormone therapy, and as part of feminizing hormone therapy for transgender women. They can also be used in the treatment of hormone-sensitive cancers like breast cancer and prostate cancer and for various other indications. Estrogens are used alone or in combination with progestogens. They are available in a wide variety of formulations and for use by many different routes of administration. Examples of estrogens include bioidentical estradiol, natural conjugated estrogens, synthetic steroidal estrogens like ethinylestradiol, and synthetic nonsteroidal estrogens like diethylstilbestrol. Estrogens are one of three types of sex hormone agonists, the others being androgens/anabolic steroids like testosterone and progestogens like progesterone.

Side effects of estrogens include breast tenderness, breast enlargement, headache, nausea, and edema among others. Other side effects of estrogens include an increased risk of blood clots, cardiovascular disease, and, when combined with most progestogens, breast cancer. In men, estrogens can cause breast development, feminization, infertility, low testosterone levels, and sexual dysfunction among others.

A sex-hormonal agent, also known as a sex-hormone receptor modulator, is a type of hormonal agent which specifically modulates the effects of sex hormones and of their biological targets, the sex hormone receptors. The sex hormones include androgens such as testosterone, estrogens such as estradiol, and progestogens such as progesterone. Sex-hormonal agents may be either steroidal or nonsteroidal in chemical structure and may serve to either enhance, inhibit, or have mixed effects on the function of the sex hormone systems.

Sex-hormonal agents are used in medicine for a variety of purposes including hormone therapy (e.g., menopausal hormone therapy, androgen replacement therapy, transgender hormone therapy), antihormone therapy (e.g., androgen deprivation therapy, estrogen deprivation therapy), and hormonal contraception, among others.

Progestogen-only injectable contraceptives (POICs) are a form of hormonal contraception and progestogen-only contraception that are administered by injection and providing long-lasting birth control. As opposed to combined injectable contraceptives, they contain only a progestogen without an estrogen, and include two progestin preparations:

• Medroxyprogesterone acetate (brand names Depo-Provera, Provera, Depo-subQ Provera 104) – 150 mg (intramuscularly) or 104 mg (subcutaneously) every 3 months
• Norethisterone enanthate (brand names NET EN, Noristerat, Norigest, Doryxas) – 200 mg (intramuscularly) every 2 months

Combined injectable contraceptives (CICs) are a form of hormonal birth control for women. They consist of monthly injections of combined formulations containing an estrogen and a progestin to prevent pregnancy.

CICs are different from progestogen-only injectable contraceptives (POICs), such as depot medroxyprogesterone acetate (DMPA; brand names Depo-Provera, Depo-SubQ Provera 104) and norethisterone enantate (NETE; brand name Noristerat), which are not combined with an estrogen and are given once every two to three months instead of once a month.

Progesterone (P4), sold under the brand name Prometrium among others, is a medication and naturally occurring steroid hormone. It is a progestogen and is used in combination with estrogens mainly in hormone therapy for menopausal symptoms and low sex hormone levels in women. It is also used in women to support pregnancy and fertility and to treat gynecological disorders. Progesterone can be taken by mouth, vaginally, and by injection into muscle or fat, among other routes. A progesterone vaginal ring and progesterone intrauterine device used for birth control also exist in some areas of the world.

Progesterone is well tolerated and often produces few or no side effects. However, a number of side effects are possible, for instance mood changes. If progesterone is taken by mouth or at high doses, certain central side effects including sedation, sleepiness, and cognitive impairment can also occur. The medication is a naturally occurring progestogen and hence is an agonist of the progesterone receptor (PR), the biological target of progestogens like endogenous progesterone. It opposes the effects of estrogens in various parts of the body like the uterus and also blocks the effects of the hormone aldosterone. In addition, progesterone has neurosteroid effects in the brain.