News
Hormones used in contraception
Published: Aug 29, 2004 - 07:46 AM
Estrogen (Estradiol)
Estrogen is the major female hormone and is responsible for female characteristics. The estrogen compound used in most oral contraceptives is estradiol and is always used with a progestin.
Estrogen is the major female hormone and is responsible for female characteristics. The estrogen compound used in most oral contraceptives is estradiol and is always used with a progestin.
Effects on Reproduction. When used throughout a menstrual cycle with progesterone, it suppresses the actions of other reproductive hormones (luteinizing hormone, or LH, and follicle stimulating hormone, or FSH) and prevents ovulation. Estrogen also changes the cellular structure of the lining of the uterus (the endometrium) and hinders implantation of a fertilized egg.
Side Effects of Estrogen. During the first two or three months of use of oral contraceptives, side effects from estrogen in the combined pill includes:
* Nausea and vomiting. (Can often be controlled by taking the pill during a meal or at bedtime.)
* Headaches. (In women with a history of migraines, they may worsen.)
* Dizziness.
* Breast tenderness and enlargement.
* Estrogen has widespread effects on many other bodily functions, including increasing bone density. It has mixed effects on heart. It appears to improve cholesterol and other lipid levels. However, it also increases blood clotting and may increase the risk for stroke in certain women.
New OC preparations with estrogen at lower doses (20 mcg and below) may reduce these side effects, and improve the effects on heart and circulation. Such preparations, however, may also increase spotting and break-through bleeding, depending on the progestin used.
Progesterone (Progestin)
When used in contraception, progesterone is referred to by one of several names:
* Progesterone is actually the name for the natural hormone
* Progestogen is a synthetic form, and
* Progestin is the term for any agent, natural or synthetic, that causes progesterone effects. It is used as the general term in this report.
Effects on Reproduction. Progestins may be used alone or with estrogen in oral contraceptives. In addition, certain specific progestins are used in other kinds of contraceptives, such as levonorgestrel in the Norplant system and depo-medroxyprogesterone acetate in the injected Depo-Provera.
Progesterone can prevent pregnancy by itself in a number of ways:
* It blocks luteinizing hormone (LH), one of the reproductive hormones important in ovulation.
* It maintains a powerful barrier against the entry of sperm into the uterus by keeping the cervical mucus thick and sticky.
* It reduces the mobility of th fallopian tubes, thereby inhibiting sperm transport.
* It changes the lining of the uterus and makes it more difficult for the fertilized egg to implant.
Progestins used in contraceptives are referred to as
* Second generation (e.g. levonorgestrel, norethisterone) and
* Third generation (e.g. desogestrel, gestodene, norgestimate, drospirenone). The third generation progestins tend to have fewer male-like side effects. Some studies suggest, however, they may pose a higher risk for blood clots than the older progestin, although the risk is still small. They possibly may have a better effect on cholesterol levels than earlier progestins, but this does not seem to translate into any particular heart benefits.
Side Effects of Progestins. Side effects of progestin occur in both the combination oral contraceptives and any contraceptive that only uses progestin, although they may be less or more severe depending on the form and dosage of the contraceptive. Side effects may include the following:
* Changes in uterine bleeding. Such as higher amounts during periods, spotting and bleeding between periods (called break-through bleeding), or absence of periods. Be sure to check with the physician if any of these occur.
* Unexpected flow of breast milk. (Check with the physician if this occurs to be sure other abnormalities are not causing it.)
* Abdominal pain or cramps.
* Diarrhea.
* Fatigue, unusual tiredness, weakness.
* Hot flashes.
* Decreased sex drive.
* Nausea .
* Trouble sleeping.
* Acne or skin rash. (Low-dose OCs actually improve acne. Only Ortho Tri-Cyclen is approved for this.)
* Depression, irritability, or other mood changes.
* Swelling in the face, ankles, or feet.
* Weight gain.
Newer formulations of combination pills that use low-dose estrogen and newer progestins may reduce and even avoid many of these side effects. Progestins used in non-oral contraceptives, such as the LNG-IUS IUD, also may not pose as high a risk for these side effects. If side effects persist or are severe, a woman should always talk to her physician. Many women do not experience these side effects, or if they do, their bodies eventually adjust.
Side Effects of Estrogen. During the first two or three months of use of oral contraceptives, side effects from estrogen in the combined pill includes:
* Nausea and vomiting. (Can often be controlled by taking the pill during a meal or at bedtime.)
* Headaches. (In women with a history of migraines, they may worsen.)
* Dizziness.
* Breast tenderness and enlargement.
* Estrogen has widespread effects on many other bodily functions, including increasing bone density. It has mixed effects on heart. It appears to improve cholesterol and other lipid levels. However, it also increases blood clotting and may increase the risk for stroke in certain women.
New OC preparations with estrogen at lower doses (20 mcg and below) may reduce these side effects, and improve the effects on heart and circulation. Such preparations, however, may also increase spotting and break-through bleeding, depending on the progestin used.
Progesterone (Progestin)
When used in contraception, progesterone is referred to by one of several names:
* Progesterone is actually the name for the natural hormone
* Progestogen is a synthetic form, and
* Progestin is the term for any agent, natural or synthetic, that causes progesterone effects. It is used as the general term in this report.
Effects on Reproduction. Progestins may be used alone or with estrogen in oral contraceptives. In addition, certain specific progestins are used in other kinds of contraceptives, such as levonorgestrel in the Norplant system and depo-medroxyprogesterone acetate in the injected Depo-Provera.
Progesterone can prevent pregnancy by itself in a number of ways:
* It blocks luteinizing hormone (LH), one of the reproductive hormones important in ovulation.
* It maintains a powerful barrier against the entry of sperm into the uterus by keeping the cervical mucus thick and sticky.
* It reduces the mobility of th fallopian tubes, thereby inhibiting sperm transport.
* It changes the lining of the uterus and makes it more difficult for the fertilized egg to implant.
Progestins used in contraceptives are referred to as
* Second generation (e.g. levonorgestrel, norethisterone) and
* Third generation (e.g. desogestrel, gestodene, norgestimate, drospirenone). The third generation progestins tend to have fewer male-like side effects. Some studies suggest, however, they may pose a higher risk for blood clots than the older progestin, although the risk is still small. They possibly may have a better effect on cholesterol levels than earlier progestins, but this does not seem to translate into any particular heart benefits.
Side Effects of Progestins. Side effects of progestin occur in both the combination oral contraceptives and any contraceptive that only uses progestin, although they may be less or more severe depending on the form and dosage of the contraceptive. Side effects may include the following:
* Changes in uterine bleeding. Such as higher amounts during periods, spotting and bleeding between periods (called break-through bleeding), or absence of periods. Be sure to check with the physician if any of these occur.
* Unexpected flow of breast milk. (Check with the physician if this occurs to be sure other abnormalities are not causing it.)
* Abdominal pain or cramps.
* Diarrhea.
* Fatigue, unusual tiredness, weakness.
* Hot flashes.
* Decreased sex drive.
* Nausea .
* Trouble sleeping.
* Acne or skin rash. (Low-dose OCs actually improve acne. Only Ortho Tri-Cyclen is approved for this.)
* Depression, irritability, or other mood changes.
* Swelling in the face, ankles, or feet.
* Weight gain.
Newer formulations of combination pills that use low-dose estrogen and newer progestins may reduce and even avoid many of these side effects. Progestins used in non-oral contraceptives, such as the LNG-IUS IUD, also may not pose as high a risk for these side effects. If side effects persist or are severe, a woman should always talk to her physician. Many women do not experience these side effects, or if they do, their bodies eventually adjust.
