Hormonal Methods of Birth Control (cont.)

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Oral hormones: the pill

The pill for women is an oral contraceptive made from synthetic hormones. The pill is considered to be 97% to 99% effective if used properly. The pill is also fully reversible. The pill has been available since 1960, and it is estimated that more than 10 million American women currently use birth-control pills.

There are two types of birth-control pills available:

  • the combination pill and
  • the progestin-only pill, known as the minipill.

The combination pill: The combination pill contains the hormones estrogen and progestin, a form of progesterone. When a woman uses the combination pill, the eggs in her ovaries do not mature and she does not ovulate. She doesn't become pregnant because no egg is available to be fertilized by a sperm.

The traditional combination pill comes in 21-day packs or 28-day packs depending on the manufacturer. The 21-pill pack has pills for 21 "on" days and no pills for the seven "off" days that follow. The 28-pill pack has active pills for the first 21 "on" days and seven inactive (placebo) or reminder pills for the following seven "off" days.

New preparations have been developed that allow for extended or continuous use of combination pills. These products allow for a reduction in the number of menstrual periods a woman experiences.

The minipill: The minipill only contains one hormone, progestin. Progestin thickens the cervical mucus, making it more difficult for sperm to pass through the cervix. It also makes the lining of the uterus less receptive to the implantation of a fertilized egg. The progesterone-only pill is sometimes recommended for women who have medical reasons for which they must avoid taking estrogen hormones. (These reasons can include liver disease, certain types of blood clots in the veins, breast cancer, and uterine cancer.) In addition, it is often recommended in nursing mothers because it has no adverse affects on breastfeeding. Indeed, extended breastfeeding, as well as delay in the need for formula supplementation has been observed in breastfeeding users of the minipill.

The minipill is taken every day. There are no "on" or "off" days with the minipill.

No matter which type of birth-control pill a woman uses, she should take it every day at the same time in order to establish a routine. The woman needs to minimize the chance she will forget to take the pill, which is not an uncommon occurrence. This is especially critical in the case of the progestin-only pill (minipill). Forgetting to take the minipill, or taking it at varying times of the day, can significantly impair its effectiveness in contraception. This is due to the low dose of the minipill causing its effects to wear off rapidly if the pill is missed.

When a woman begins taking the pill, she may not protected from pregnancy until she has been taking the pill for 10 consecutive days in a row. If a woman forgets to take a pill after she has started, she may be at risk for getting pregnant.

If she only misses one pill, she should take it as soon as she remembers, even if it means taking two pills in the same day. If she misses two pills, she should take both of them as soon as she remembers, plus the pill for that day at her regular time. If she misses three pills, she should discontinue use of the pill for four more days to complete one week and then begin taking a new pack of birth control pills, whether she has a menstrual period or not. She must use an alternate form of birth control or abstain from sexual activity during the week that she stops taking her pills. If a woman continually forgets to take her pills, perhaps she should consider a different method of birth control.

The pill may partially lose its effectiveness if a woman vomits or has diarrhea for any reason. Some medications, including certain sedatives and some antibiotics such as penicillin and tetracycline, may reduce the effectiveness of the pill. Research in this area is ongoing. A woman should ask her health-care professional about these matters and the necessity of using a backup method of birth control if any of these conditions exist.

Some women experience temporary symptoms of spotting or light vaginal bleeding, breast tenderness, and nausea during the first one to three months of taking the pill. Nausea can be helped if the pill is taken after a meal. While women sometimes fear weight gain with oral contraceptives, studies of the low-dose preparations demonstrate that there is no significant weight gain with oral contraception and no major difference in weight change comparing various contraception products. Negative mood changes, such as depression, and pigmented patches of skin on the face (melasma) may occur with oral-contraceptive use. Because the progesterone in women can cause thinning of the lining of the uterus, some women may experience loss of menstrual periods (amenorrhea). Oral contraceptive-induced amenorrhea happens in about 1% of women in the first year of use. As long as the woman is properly taking her pills, amenorrhea is not harmful and it does not signal any loss of effectiveness of the pills. Most side effects from the combination pill or the minipill decrease after two to three months of use. It is important to remember that because most side effects of oral contraceptives decrease in the first two to three months of use, women should try to avoid switching pills prior to an adequate trial. Trying to stick with any given product for two to three months may be necessary to really determine whether or not it will be tolerated over time. Switching too early to another brand may only needlessly subject the woman to the possibility of similar side effects starting all over again with the new pill.

There is no increased risk of birth defects in babies born to women who have taken the pill, but a woman should not use either type of pill if she is pregnant. A woman who is breastfeeding should not use the combination pill because it can reduce the amount of her breast milk and the concentration of proteins and fat in her breast milk. Additionally, her breast milk will contain traces of the hormones from the pill. However, in contrast to the combination pill, the minipill is routinely used in lactating women.

Women who smoke and take the pill are at increased risk of heart disease and stroke. There is no increased risk of heart attack or stroke among healthy nonsmoking women who use the pill. Blood clots in the legs and elsewhere are slightly more frequent with low-dose oral contraceptives, but the risk is very low, and lower than the increased risk of clotting that occurs with pregnancy. Nevertheless, oral contraceptives are not recommended for women with clottingtendencies (such as antiphospholipid antibody syndrome, Leiden Factor 5), known coronary heart disease, stroke, unevaluated breast lumps, vaginal bleeding, or breast cancer. Smokers over 35 years of age should not use oral contraceptives, nor should women with a significant liver disorder.

A woman should contact her health-care professional immediately if she experiences any of these side effects while taking the pill:

There are a number of benefits to taking the pill. Both the combination pill and the minipill can regularize a woman's menstrual cycle and reduce her menstrual flow and menstrual cramps. There is evidence that the pill protects against cancer of the ovary and uterus as well as pelvic inflammatory disease (PID) and iron deficiency anemia. The combination pill can reduce acne (although maximal acne reduction may take six months to occur), the risk of an ectopic pregnancy, noncancerous breast cysts, and ovarian cysts. According to a large study, the combination pill confers no long-term risk of breast cancer. In addition, a woman who has taken the pill is less likely to develop rheumatoid arthritis and osteoporosis. Users of oral contraceptives have experienced significant decreases in excessive menstrual flow and in occurrence and severity of menstrual cramps.

A woman's menstrual periods should begin again within about 3 months of stopping the oral-contraceptive pill. However, the length of delay before a woman's period returns after stopping the pill varies from woman to woman. Oral contraceptives are about 97% effective inpreventing pregnancy. The pill does not protect a woman against sexuallytransmitted infections.

Medically Reviewed by a Doctor on 2/27/2014

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