How Oral Contraceptives Work

The pill works primarily by stopping ovulation (release of an egg). Pills must be swallowed every day, at the same time of the day, in order for them to be effective. Taken as directed, only about 1 in 1,000 women is expected to become pregnant in the first year of use. Among pill users in the United States, about 3% become pregnant in the first year typically.

You may start taking your pills according to one of several different schedules. Our clinicians recommend starting the pill on the first Sunday after your period begins, or if you have just had an abortion, on the first Sunday after the abortion procedure was done.

A good way to remember to take the pill is to associate taking your pill with something else that you do at the same time every day, such as going to bed, eating a meal, or brushing your teeth. You need to keep a steady level of hormones in your system. Check your pack of birth control pills each morning to make sure you took your pill the day before.

Do I Need to Use a Back-up Method?

You should always have a back-up method such as a condom or spermicides (withdrawal is not a back-up) on hand in case you:

• run out of pills
• forget to swallow your pills
• experience a serious pill warning signal and discontinue pill use
• want protection from STDs and AIDS
• have repeated episodes of breakthrough bleeding (could mean decreased pill effectiveness)

Many pregnancies occur when women stop taking their pills, fail to start another birth control method, and have unprotected sex. All women starting the pill should have a back-up method on hand at all times.

Be sure to tell your clinician if you are taking any medications (including over-the-counter medications). The effectiveness of birth control pills may be decreased by drugs that change liver function or decrease your body's ability to absorb the hormones. Some of the most common medications that do this are antibiotics, antacids, laxatives, narcotics, and diet pills.

See your FDA instruction sheet for a complete list of medications that interact with the pill and ask your clinician about them. Always use your back-up if you take these medications.

If you have diarrhea or vomitting, start using your back-up method immediately and continue doing so until your next period.

If you miss pills, consult your FDA instructions, or call your clinician.

Advantages

• Very effective. Pills are a very effective method of birth control when taken consistently and correctly.
• Very safe. Pills are very safe for most women as long as they do not have a specific reason to avoid using pills.
• Reversible. A woman will not lose her fertility by using pills.
• Menstrual Cycle Benefits
  • Decrease in menstrual cramps and pain
  • Decrease in number of days of bleeding and blood loss during periods
  • For some women, a reduction in PMS symptoms such as anxiety, depression, headaches, and fluid retention.
• Protective effect against Pelvic Inflammatory Disease (PID), a major cause of female infertility.
• Prevention of ovarian and endometrial cancer
• Decreased risk for benign breast disease
• Ectopic pregnancy prevention
• Acne improvement
• Enhanced sexual enjoyment. For some women, the pill enhances sexual enjoyment and increases spontaneity.
• Emergency hormonal contraception. Please see our page on the Morning After Pill for information on Emergency Contraception.

Disadvantages and Cautions

• Must be taken daily. Pills must be taken daily at the same time or they will not work.
• Can be expensive. If bought in pharmacies, pills can become very expensive.
• Unwanted menstrual changes. Pills may be associated with unwanted menstrual changes such as missed periods, scant bleeding, spotting, or breakthrough bleeding (bleeding between periods).
• Nausea. This usually goes away within the first few cycles.
• Headaches
• Depression or other mood changes
• Decreased libido. For some women, pills cause a decrease in sex drive.

Should I ever take a break from the Pill?

Many women can safely use pills throughout their reproductive years as long as they do not have any specific reasons to avoid using pills. A rest period every few years is defintiely not recommended for women wishing to continue using pills. Pills may be used for many years cumulatively or consecutively without increasing a woman's risk for complications.

Medical Risks

The following are medical considerations for every patient to be aware of. If you have problems or a family history of problems with what is listed below, speak with your clinician about your specific risks for using the pill.

• Glucose intolerance
• Gallbladder disease
• Circulatory system diseases such as thrombophlebitis or pulmonary emboli. This is more likely to occur in women who are:
  • smokers
  • sedentary
  • overweight
  • over 50 years old
  • hypertensive, diabetic, or have a history of heart or vascular disease
  • diabetic or family history of diabetes
  • family history of heart attack under age 50
  • high cholesterol or high LDL/HDL ratio

Warning Signs

Know the pill warning signals. Any one of these symptoms can mean that you in serious trouble:

• Severe abdominal pain
• Severe chest pain, cough, shortness of breath
• Severe headaches, dizziness, weakness or numbness
• blurry vision or vision loss, speech problems
• Severe leg pain (calf or thigh)

Call your clinician immediately if you experience any of these problems or if you develop depression, yellow jaundice, a breast lump, a bad fainting attack or collapse, a seizure, difficulty speaking, high blood pressure (above 150/90), an allergic rash, or if you are immobilized after an accident or major surgery.

If you smoke, stop smoking. If you don't, you must watch for the pill warning signs. If you smoke, you must stop taking the pills at age 35.

Cancer and the Pill

There is not type of cancer definitely known to be more common in pill users. Pills, however, do make women less likely to develop three types of cancer: ovarian cancer, endometrial cancer, and molar pregnancies. Pills also make women less likely to develop several benign tumors or masses: benign breast masses, fibroids, and ovarian cysts.

There is, however, one benign tumor of the liver called a hepatic adenoma that has been found to be more likely to develop in women using pills. Fortunately, these tumors are very rare and pills are probably not associated with an increased risk for liver cancer.

Although research is not yet conclusive on other cancers, pills probably have no effect on a woman's likelihood of developing a malignant melanoma; kidney, colon, or gall bladder cancer; or pituitary tumors. Studies on breast cancer, cervical cancer, and cancer of the liver are all still inconclusive. In general, bye age 55, a woman is less likely to be diagnosed with cancer if she has used pills that if she used not method at all.

Source: All of the above information was taken from: Hatcher, RA et.al. (1994). Contraceptive Technology 16th edition. New York: Irvington Publishers, Inc.