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Birth Control Overview (cont.)

Hormonal Methods of Birth Control

Birth control pills

Birth control pills, also known as oral contraceptives, have been marketed in the United States since 1962. Over the past 40 years, there have been changes in the types of estrogen and progestin (hormones) used in the pills and lower amounts of hormones overall.

According to the Centers for Disease Control and Prevention, the birth control pill is the leading birth control method used by women younger than 30 years. Birth control pills today are designed to improve safety and reduce side effects. Lower doses of estrogen are associated with a decrease in side effects, such as breast tenderness, and nausea.

Birth control pills are usually taken by mouth and swallowed with a liquid. In late 2003, the FDA approved a spearmint-flavored chewable birth control pill called Ovcon 35. They contain the same hormones that are in standard birth control pills. You may chew the pills or swallow them whole. If you chew the pill, you should drink 8 ounces of water afterward to make sure the full dose reaches your stomach. Over 30 different combinations of birth control pills are available in the United States. The majority of the combinations of these pills have 21 hormonally active pills followed by 7 pills containing no hormones. A woman begins taking a pill on the first day of her period or the first Sunday after her period has begun. By taking a pill a day, a woman can usually take pills consistently throughout her cycle.

  • Monophasic pills: These have a constant dose of both estrogen and progestin in each of the hormonally active pills.
  • Phasic pills: These combinations can alter either or both hormonal components to try to mimic the natural menstrual cycle.
  • 91-day pill: The FDA has approved a number of birth control pills that you take for 12 weeks (84 days) followed by 1 week (7 days) of an inactive pill. A menstrual period occurs during that week, every three months. The pills contain the hormones already approved for other, 28-day birth control pills.

If a woman misses 1 or 2 pills, she should take 1 tablet as soon as it is remembered. She then takes 1 tablet twice daily until each of the missed pills has been accounted for. Women who have missed more than 2 consecutive pills should be advised to use a backup method of birth control at the same time, finishing up the packet of pills until her next period. The pills prevent ovulation (release of an egg) and thus prevent pregnancy.

  • How effective: Pregnancy rates range from 0.1% with perfect use to 5% with typical use.
  • Advantages: Birth control pills are used to treat irregular menstrual periods. Women can manipulate the cycle to avoid a period during certain events, such as vacations or weekends by extending the number of intake days of hormonally active pills or by skipping the nonactive pill week. Birth control pills help prevent certain conditions, such as benign breast disease, pelvic inflammatory disease (PID), and functional cysts. Functional cysts are reduced by the suppression of stimulation of the ovaries. Ectopic pregnancies are prevented by the cessation of ovulation. Birth control pills have been known to prevent certain ovarian and endometrial cancers.
  • Disadvantages: Problems in taking birth control pills include nausea, breast tenderness, weight gain, breakthrough bleeding, no periods, headaches, depression, anxiety, and lower sexual desire. Birth control pills do not provide protection from STDs. It’s important to take the pills daily and consistently (same time every day). If a woman stops taking birth control pills, it may take her a few months to get her normal ovulatory cycle back. After 6 months, she may need to be examined by her health care provider.
  • Additional risks: Some women may be at risk for blood clots (venous thrombosis). At particular risk are heavy smokers (especially those older than 35 years), women with high or abnormal blood lipids (cholesterol levels), and women with severe diabetes, high blood pressure, and obesity.

The association of birth control pill use and breast cancer in young women is controversial. The Collaborative Group on Hormonal Factors in Breast Cancer performed the most comprehensive study to date in 1996. The results demonstrated that current pill users, and those who had used birth control pills within the past 1-4 years, had a slightly increased risk of breast cancer. Although these observations support the possibility of a marginally elevated risk, the group noted that the pill users had more breast examinations and breast imaging than the nonusers. Thus, although the consensus states that birth control pills can lead to breast cancer, the risk is small and the resulting tumors spread less aggressively than usual. Current thought is that birth control pill use may be a cofactor that can interact with another primary cause to stimulate breast cancer.

The relationship between birth control pill use and cervical cancer is also quite controversial. Important risk factors include early sexual intercourse and exposure to the human papillomavirus. The thinking now is that if birth control pills increase the risk of cervical cancer, the risk is small and related to risky behavior. Thus, women who use birth control pills should have an annual Pap test.

Progestin-only birth control pills

Progestin-only pills, also known as the mini-pill, are not used widely in the United States. Fewer than 1% of users of oral contraceptives use them as their only method of birth control. Those who use them include women who are breastfeeding and women who cannot take estrogen.

Birth control patch

There is in the United States a transdermal patch (you wear it on your skin) that releases estrogen and progesterone directly into the skin (brand name: Ortho Evra). Each patch contains a 1-week supply of hormones. It releases a low daily dose equivalent to the lowest-dose oral contraceptive. It’s easy for women to use because it works for a week, and women don’t have to remember a pill every day. You apply a new patch every week for 3 weeks and do not wear a patch during the fourth week when you have a menstrual period. It is available by prescription. Side effects are similar to those experienced by women using oral contraceptives. The patch may cause skin irritation where it is placed (near the bikini line or on the buttocks or upper body). Sometimes it may come off and not be noticed, for example, in the shower, and it will be less efficient. In August, 2002, the FDA listed a failure rate for the patch of 1 pregnancy per 100 women per year, similar to that of other combination methods. It may be less effective for women who weigh more than 198 pounds. The patch does not protect against STDs.

Vaginal ring

The vaginal ring (NuvaRing) is a newer form of birth control. The actual design of vaginal rings as birth control was first developed in the 1970s. Vaginal rings can deliver progesterone or progesterone/estrogen combinations. The hormones are released slowly and absorbed directly by the body. Preliminary studies show they safely prevent pregnancy, like birth control pills, with fewer side effects. These would be used in the same schedule as birth control pills, with 3 weeks of ring usage and 1 week without to produce a menstrual period. If the ring comes out on its own, and remains out for more than 3 hours, you must use another form of birth control until the ring has been back in place for at least 7 days. It is available by prescription. The vaginal ring does not prevent STDs.


The FDA has approved a contraceptive implant (etonorgestrel, brand name Nexplanon). It is placed in the upper arm of the woman and releases a small, steady dose of progestin. It is extremely effective and lasts for three years.

  • How effective: Implants are as effective as surgical sterilization. Overall, pregnancy rates increase from 0.2% in the first year to 0.5% by the third year.
  • Advantages: Implants last a long time. A woman can become fertile again once the implants are removed (again, surgically).
  • Disadvantages: A minor surgical procedure is necessary to put them in and to remove them. Menstrual irregularities are common, along with other side effects, including weight gain, headaches, mood changes, growth of facial hair, flow of milk from nipples, and acne. This method does not protect against STDs.
  • Additional risks: Implants are often used for women who have just had a child and are breastfeeding, for those who have trouble remembering to take birth control pills or use other birth control methods, and for women who should not get pregnant because of a medical condition. Implants are not recommended for heavy smokers, women with a history of ectopic pregnancy, diabetes, high cholesterol, severe acne, high blood pressure, heart disease, migraine, and depression.

Injections An injection of a synthetic hormone depomedroxyprogesterone acetate (DMPA, brand name: Depo-Provera) can be given every 3 months to stop ovulation. You receive it by injection in the doctor’s office. After injection, the medication is active within 24 hours and lasts for 3 months. It prevents your ovaries from releasing eggs.

  • How effective: DMPA is an extremely effective contraceptive option. Most other medications or a woman’s weight do not change its effectiveness. Within the first year of use, the failure rate is 0.3%.
  • Advantages: DMPA does not produce the serious adverse effects of estrogen, such as blood clotting. It lowers risk for certain endometrial and ovarian cancers. Problem periods may become regular.
  • Disadvantages: Some women may not have a period within the first year. Irregular bleeding can be treated by giving the next dose earlier or by adding a low-dose estrogen temporarily. Because DMPA lasts in the body for several months in women who have used it on a long-term basis, it can delay the return to fertility. About 70% of former users desiring pregnancy conceive within 12 months, and 90% of former users conceive within 24 months. Other adverse effects, such as weight gain, depression, and menstrual irregularities, may continue for as long as 1 year after the last injection. Recent studies suggest a possible link between DMPA and bone density loss. Results are conflicting and limited. This method does not protect against STDs.
Medically Reviewed by a Doctor on 6/24/2016
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