Birth control pills - combination

Alternate Names

The pill - combination; Oral contraceptives - combination; OCP - combination; Contraception - combination

What Are Combination Birth Control Pills?

Birth control pills help keep you from getting pregnant. Combination birth control pills contain both estrogen and progestin. Some combination birth control pills let you have fewer periods each year. These are called continuous or extended-cycle pills.

Types of Combination Birth Control Pills

Birth control pills come in packages. You take pills from a 21-pack once a day for 3 weeks, then you do not take pills for 1 week. It may be easier to remember to take 1 pill every day, so other pills come in a 28-pack of pills, with some having active pills (containing hormones) and some with no hormones. 

There are 5 types of combination birth control pills. Your health care provider will help you choose the one right for you.

  • One phase pills: These have the same amount of estrogen and progestin in all the active pills.
  • Two phase pills: Once each cycle, the level of hormones in these pills change.
  • Three phase pills: Every 7 days the dose of hormones changes.
  • Four phase pills: The dose of hormones in these pills changes 4 times each cycle.
  • Continuous or extended cycle pills: These keep the level of hormones up so you have few or no periods.

How Do I Start Taking Combination Pills?

  • You may take your first pill on the first day of your period.
  • You may take your first pill on the Sunday after your period starts. If you do this, you need to use another birth control method (such as a condom, diaphragm, or sponge) for the next 7 days. This is called backup birth control.
  • You may take your first pill any day in your cycle, but you will need to use another birth control method for the first month.
  • Continuous or extended cycle pills: Take one pill everyday, at the same time each day.

How Do I Take Them?

  • Take one pill every day, at the same time of day.
  • Birth control pills only work if you take one every day. If you miss a day, use a backup method.

What if I Miss a Day?

If you miss a pill, or more than one pill, use a backup method of birth control and call your health care provider right away. What to do depends on what type of pill you are taking, where you are in your cycle, and how many pills you missed. Your health care provider will help you get back on schedule.

What to Expect When I Stop

You may decide to stop taking birth control pills because you want to get pregnant or change to another birth control method. Here are some things to expect when you stop taking the pill:

  • You might become pregnant right away.
  • You may have mild spotting of blood before you get your first period.
  • You should get your period 4 to 6 weeks after you take your last pill. If you do not get your period in 8 weeks, call your health care provider.
  • Your period may be heavier or lighter than usual.
  • Your acne may return.
  • For the first month, you may have headaches or mood swings.

When to Use a Backup Method

Use a backup method of birth control, such as condom, diaphragm, or sponge if:

  • You miss one or more pills.
  • You are not starting your first pill on the first day of your period.
  • You are sick, throwing up, or have loose stools (diarrhea). Even if you take your pill, your body may not absorb it. Use a backup method of birth control for the rest of that cycle.
  • You are taking another medicine that may keep the pill from working. Tell your health care provider or pharmacist if you take any other medicines, such as antibiotics, seizure medicine, medicine to treat HIV, or St. John’s wort. Find out if what you take will interfere with the pill working.

When to Call the Doctor

Call your doctor if:·                 

  • You have swelling in your leg        
  • You have leg pain              
  • Your leg feels warm to the touch or changes in skin color           
  • You have fever or chills          
  • You are short of breath (it is hard to breathe)      
  • You have chest pain               
  • You cough up blood              
  • You have a headache that gets worse, especially a migraine with aura, after starting to take birth control pills


Family planning: Contraception, sterilizaiton, and pregnancy termination. In:Lentz GM, Lobo RA, Gershenson DM, Katz VL, eds. Comprehensive Gynecology. 6th ed. Philadelphia, Pa: Mosby Elsevier; 2012:chap 13.

Version Info

  • Last reviewed on 11/20/2012 12:00:00 AM
  • Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Bellevue, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang.

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