Birth Control Pills

Birth control pills

“The pill” is a medication used to prevent pregnancy. The pill typically refers to combined birth control pills which use two female hormones, estrogen and progestin. The hormones in the pill thicken cervical mucus, thin the lining of the uterus, and prevent a woman’s ovaries from releasing an egg (ovulation). When taken correctly, the failure rate is between 1 and 8 percent per year.

Most pill packages have active pills (with hormones) and placebo pills (no hormones). The number of placebo pills can vary depending on the type of pill. Your menstrual period should occur during the placebo pills because of lack of hormones. You are still protected from pregnancy during the placebo pills. Continuous use pills are also available. These pills reduce the number of scheduled days of bleeding by reducing the number of placebo pills or eliminating them completely.

The pill does not provide protection against sexually transmitted infections. Use latex condoms for increased protection against the transmission of STIs including HIV.

How do I begin taking the pill?

There are three options:

  • Start taking them immediately, or “quick start,” if you have had no unprotected intercourse since your last period
  • Start them on the first day of menstrual bleeding
  • Start them on the first Sunday after your menstrual bleeding begins

When should I take my pills?

Take your pills at the same time each day within about a 4 hour time frame. This will help you to remember to take your pills and gives you the most protection against pregnancy. Most people use a cell phone alarm to help them remember to take the pill on time. You can also download a pill reminder app for your cell phone. Use the days of the week stickers to put on your pill pack if you don't start them on a Sunday.

What if I forget to take the pill?

If you do forget a pill, take it as soon as you remember. If you are 24 hours late taking your pill, take both at the same time. Be sure to use a second method of contraception, such as condoms, for the next 7 days of active pills if you are 24 hours late taking a pill or you miss the first or last active pill of the pack. When you miss a pill there is an increased risk of pregnancy. If you miss two pills in a row, you may want to consider emergency contraception. Read the package information for instructions on missed pills or call your health care provider if you have any questions.

When do the pills become effective?

Pills are effective to prevent pregnancy 7 days after you start taking them consistently. Use condoms if you have trouble remembering to take your pill on time because you may be at risk for pregnancy. If you have trouble remembering to take your pill on time you may want to consider a non-daily form of contraception. You can make an appointment to discuss this with your health care provider.

Are there times I need to use supplemental contraception?

Use condoms in addition to pills if:

  • You want to decrease your risk of infection
  • You suspect you or your partner have a sexually transmitted infection
  • You missed taking pills for 48 hours or more
  • You were late starting your new pill pack
  • You had severe vomiting or diarrhea
  • You have to take medications that lower the body’s ability to absorb contraceptive hormones (check with the provider who prescribed the medication)

You should consider the pill a medication that you take regularly. Other medications may interfere with the effectiveness of the pill and the pill can interfere with the effectiveness of some medications. It is important to report that you are on the pill if you are prescribed a new medication.

What if I lose a pill?

You should take another pill of the same color. If that’s not possible, you may take the next pill from your package, even if it’s not the same color. Taking a placebo as a replacement pill will not provide protection against pregnancy.

What can I expect my periods to be like?

Your periods will generally be lighter, shorter, and with less cramping. Some women have very little bleeding or may skip periods. This is common if you take a pill that has fewer than seven placebo pills. If you are sure you have taken all your pills on time, don’t worry. Do NOT stop your pills unless directed to do so by your health care provider.

What about spotting or bleeding between periods?

Minor spotting or bleeding between periods is not uncommon and tends to disappear after the first 3 months. Bleeding or spotting may also be due to missing pills or taking them at irregular times. If you are worried or the bleeding is heavy, call your health care provider.

What additional health benefits can pills provide?

The pill may be beneficial to your health and give you benefits for long terms.

They may provide REDUCED RISK of:

  • Endometrial cancer
  • Ovarian cancer
  • Ovarian cysts
  • Benign (fibrocystic) breast disease
  • Pelvic inflammatory disease (PID)
  • Ectopic pregnancy
  • Iron deficiency anemia
  • Menstrual cycle irregularities
  • Menstrual cramps

Who shouldn’t take pills?

Tell your health care provider if you’ve had a history of blood clots; heart attack; stroke; cancer of the breast, cervix, or uterus; jaundice; migraine with aura; or if you are currently pregnant.

What are possible complications or side effects of the pill?

Birth control pills increase the risk of blood clots in veins and arteries. The risk of a blood clot is extremely small in young, healthy women. The highest risk is seen in older women and women who smoke. However, pregnancy causes an even greater risk of blood clots than does taking birth control pills. Clots in the veins can cause thrombophlebitis (mostly in the leg) and pulmonary embolism (a blood clot that travels to the lungs). Clots in arteries cause heart attacks or strokes. Know the warning signs of these problems (see below) and get medical evaluation immediately if they occur. We advise women to quit smoking if they want to use birth control pills because smoking also increases risk of blood clots and makes your pill less effective.

If I’m on the pill, what symptoms should I watch out for?

Call your health care provider or seek emergency care if you have:

  • A—Abdominal pain that is severe and cannot be explained
  • C—Chest pain that is severe or sudden or shortness of breath
  • H—Headache that is unusual or suddenly severe with numbness or weakness
  • E—Eye problems such as blurred vision, flashing lights or blindness
  • S—Severe leg pain in the calf or thigh with redness and heat

Side effects

Most side effects are temporary, lasting from 1-3 months, such as:

  • Nausea.
  • Skin changes (improvement or worsening of acne or brown patches).
  • Change in amount of vaginal discharge.
  • Temporary fluid retention.
  • Emotional changes, depression, or anxiety. (If depression or anxiety is severe, consult a health care provider.)
  • Change in sexual desire.
  • Breast tenderness/increase in size.

Weight gain with most pills is not common.

It is difficult to predict whether you will have side effects from taking the pill. Birth control pills may also cause migraines, gall bladder problems, and rarely a benign liver tumor.

It is a good idea to have your blood pressure checked after being on the pill for 2-3 months because the pill can sometimes elevate blood pressure. If your blood pressure is over 140/90 on the pill, you should notify your provider.

Stopping the pill

Once you stop pills, your fertility returns to normal rapidly. For some women there may be a delay of up to several months before normal periods resume. See your health care provider if you do not have a period within three months of stopping pills.

If you decide that you want to get pregnant, see your health care provider for preconception counseling. Start taking prenatal vitamins or folic acid 30 days before trying to get pregnant. If you accidentally get pregnant while on pills, there is no increased risk of miscarriage or birth defects.

Additional resources

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