Birth control is a way to prevent pregnancy. There are many different birth control methods. Some of these methods also reduce the risk for sexually transmitted infections (STIs).

The birth control pill, often referred to as "the pill," is a form of birth control used by women that is taken by mouth to prevent pregnancy. When taken correctly, it is 98% effective. However, the pill does not protect against STIs, including HIV (the virus that causes AIDS). The male latex condom provides the best protection from most STDs.

How does the pill work?

Normally, a woman becomes pregnant when an egg released from her ovary (the organ that holds her eggs) is fertilized by a man's sperm. The fertilized egg attaches to the woman's womb (uterus), where it receives nourishment and develops into a fetus.

Hormones in a woman's body control the release of the egg from the ovary and prepare the body to accept a fertilized egg. The pill contains a small amount of synthetic hormones. These hormones work with the body's natural hormones to prevent pregnancy. Some forms of the pill stop the body from releasing an egg from the ovary (called ovulation). Others work by making the lining of the womb too thick or too thin to accept the fertilized egg.

What does the pill contain?

Most pills contain a combination of two female hormones—estrogen and progestin. Different pills contain various strengths of these hormones. The "mini" pill only contains progestin.

Where can I get birth control pills?

Birth control pills are only available with a doctor's prescription.

How are the pills packaged?

You will receive a set of pills packaged in a thin case. Now the FDA has approved birth control pills for extended cycles beyond the traditional one-month cycle. These are packages that contain continuous active pills for one month or three months.

Other options are 21 active pills with seven placebo or sugar pills to complete a 28-day cycle. A pack of 21 active pills with four placebo pills is also available. The placebo pills do not contain hormones and are used when you expect to have a menstrual flow. They are added to remind you to start a new pill pack after 28 days.

Talk to your doctor about which options are best for you.

How do I take the first pill pack?

Ask your doctor when you should start your pill pack. You will begin your pill pack after you have your period. If you still have your period on the day that you have been told to start your pill pack, go ahead and start the pill pack. You will get your next period about 25 days after starting the pill pack.

It's best to take the pills at the same time every day. Take the pill each day either before breakfast or at bedtime. Some people find it helpful to set a timer or place a daily reminder in a calendar.

When do I start another pill pack?

You will start each new pill pack on the same day of the week. For example, if you start your first pill pack on a Sunday, you will start you next pill pack on a Sunday.

If you are on the 21-day pill pack, start the new pill pack 7 days after you finished the old pill pack. If you are on the 28-day pill pack, begin the new pack after taking the last pill in the old pack.

Start your new pill pack as scheduled above, whether or not you get your period or are still having your period.

How soon does the pill work?

Your body will need about 1 to 3 months to adjust to the pill. Use another form of birth control, such as latex condoms and foam, during the first month. After the first month, you can use only the pill for birth control.

What if I forget to take a pill?

If you forget to take a pill, take it as soon as you remember. If you don't remember until the next day, go ahead and take two pills that day. If you forget to take your pills for two days, take two pills the day you remember and two pills the next day. You will then be back on schedule. If you miss more than two pills, wait for your next period and start a new pill pack as you did when you first started taking the pill.

Any time you forget to take a pill, you must use another form of birth control until you finish the pill pack. When you forget to take a pill, you increase the chance of releasing an egg from your ovary. If you miss your period and forgot to take one or more pills, get a pregnancy test. If you miss two periods even though you have taken all your pills on schedule, get a pregnancy test. If you have any questions about missing doses or if you have pregnancy concerns, call your doctor.

Are there side effects associated with the pill?

Yes, although the majority are not serious. They include:

  • Nausea
  • Weight gain (usually less than five pounds)
  • Sore or swollen breasts
  • Small amount of blood, or spotting, between periods
  • Lighter periods
  • Mood changes

The following side effects, easily remembered by the word "ACHES," are less common but more serious. If you experience any of these, contact your doctor immediately. If you cannot reach your doctor, go to an emergency room or urgent care center for evaluation. These symptoms may indicate a serious disorder, such as liver disease, gallbladder disease, stroke, blood clots, high blood pressure, or heart disease. They include:

  • Abdominal pain (stomach pain)
  • Chest pain
  • Headaches (severe)
  • Eye problems (blurred vision)
  • Swelling and/or aching in the legs and thighs

Can any woman take the pill?

The pill can be taken safely by most women, but is not recommended for women who are over the age of 35 and smoke. Non-smokers can use the pill until menopause. You should not take the pill if you have had:

  • Blood clots
  • Inflammation in the veins
  • Serious heart or liver disease
  • Unexplained vaginal bleeding
  • Cancer of the breast or uterus
  • Sickle cell anemia

Be sure to inform your doctor if you have a first-degree relative (parent, brother, sister, child) who has had blood clots in the legs or lungs. The pill can elevate blood pressure if you have a history of hypertension. This needs to be monitored closely.

Is it ok to take other drugs while taking the pill?

Some drugs can stop the pill from working properly. Tell your doctor about all of the medicines you are taking including antibiotics, herbal medications, and anti-seizure medications.

How do mini pills work?

Mini pills work by thickening the cervical mucus so the sperm can't reach the egg. The hormone in the pills also changes the lining of the uterus, so implantation of a fertilized egg can't occur. In some cases, mini-pills stop ovulation (the release of an egg). A pill is taken every day.

How effective are mini pills?

If mini pills are used consistently and correctly, they are about 95% effective.

What is emergency contraception or Plan B?

These are higher doses of estrogen and progesterone pills dispensed by a pharmacist and are most effective within 24 hours of unprotected sex. However, they can be used up to five days after unprotected sex. You do not need a prescription for this medication if you are older than 17. If you are taking birth control pills, resume your pills after emergency contraception. This is not an ongoing form of contraception and you can still get pregnant after completing the course of medication.

Points to keep in mind when taking the pill:
  • Keep another form of birth control, like foam and condoms, on hand in case you forget to take a pill.
  • Carry your pills with you if you don't always sleep at home.
  • Get your pill refills soon after you start the last pill pack. Don't wait until the last minute.
  • Birth control pills are medication. Always inform your doctor or pharmacist that you are on the pill.
  • You are less likely to forget your pills if you take them in the morning when you get up.

There are other forms of hormonal contraception besides the pill including: the vaginal ring (NuvaRing®), which is a contraceptive ring inserted into the vagina and left in place for three weeks; the weekly contraceptive patch (Ortho Evra®), which is applied to the skin once a week for three weeks a month; and the levonorgestrel-releasing IUD (Mirena®, which is placed in the uterus and left in place for five years.

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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 7/29/2014...#3977