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How to Take Birth Control Pills

Birth control pills (BCPs) prevent pregnancy by releasing hormones. The hormones keep eggs from being released. Most BCPs have 2 hormones called estrogen and progestin.

1 in 100 women who use BCPs become pregnant each year. Pregnancy often happens because BCPs are not taken the way they should be.

What You Will Need

Your doctor will tell you if it is safe for you use BCPs. If so, you will both decide which is the best one for you.

Steps to Take

Once you have the BCPs, follow these steps:

  1. Take the BCPs as your doctor says to. Do not skip taking pills for any reason.
  2. Start BCPs the day they are prescribed or when your doctor says to.
  3. Pills come in packs of 21, 28, or 91 pills. Some pills in each pack are blank pills. They are called placebos and do not have hormones in them. You will have your monthly period on the days you take the placebo pills.

Common Questions

Q. Does the pill keep me from getting sexually transmitted infections (STIs), like HIV infection?

A. No, a condom is the only type of birth control that can help protect you from STIs.

Q. What do I do if I am taking the pill and find out I’m pregnant?

A. You will need to stop taking the BCPs. Most women do not have problems later in their pregnancy. But, if you take BCPs in the early weeks, it increases the cnance of a miscarriage or other problems.

Q. Do I need to use another type of birth control first?

A. It depends on which BCP you decide to use and when you start taking them:

  • Pills with estrogen and progestin—Start within the first 5 days from the start of your monthly period. This will protect you against pregnancy right away. If you start at any other time during your menstrual cycle, there will be a delay in pregnancy protection. During this time, you will need to use another method of birth control.
  • Progestin-only pills—You can start at any time, but it will not take effect for at least 48 hours. During this time, you will need to use another method of birth control. It is important to take the pill at the same time each day. If you take the pill more than 3 hours past the regular time, you will need to use another method of birth control for 48 hours.

Q. What should I do if I miss a pill?

A. If you forget 2 or more pills, always use another kind of birth control, such as condoms, for the rest of the month so that you do not get pregnant.

Talk to your doctor about the best time to start taking BCPs.

Call Your Doctor

Call your doctor if you have any of these problems:

  • Headache
  • Nausea
  • Lightheadedness
  • Missed monthly periods
  • Tender breasts
  • Depression

You may be taken off the BCPs or switched to a different type to reduce these problems.


Centers for Disease Control and Prevention

The American College of Obstetricians and Gynecologists


Sex and U—The Society of Obstetricians and Gynaecologists of Canada

Women's Health Matters—Women's College Hospital


Birth control methods. Office on Women's Health website. Available at: https://www.womenshealth.gov/a-z-topics/birth-control-methods. Updated April 24, 2017. Accessed March 5, 2019.

Birth control pill. Planned Parenthood website. Available at: https://www.plannedparenthood.org/learn/birth-control/birth-control-pill. Accessed March 5, 2019.

Combined hormonal birth control: pill, patch, and ring. The American Congress of Obstetricians and Gynecologists website. Available at https://www.acog.org/Patients/FAQs/Combined-Hormonal-Birth-Control-Pill-Patch-and-Ring. Updated March 2018. Accessed March 5, 2019.

Oral contraception. EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T116852/Oral-contraceptives. Updated March 5, 2019. Accessed March 5, 2019.

2/11/2011 DynaMed Plus Systematic Literature Surveillancehttp://www.dynamed.com/topics/dmp~AN~T116852/Oral-contraceptives. Dinger J, Minh TD, Buttmann N, Bardenheuer K. Effectiveness of oral contraceptive pills in a large U.S. cohort comparing progestogen and regimen. Obstet Gynecol. 2011;117(1):33-40.

Last reviewed March 2019 by EBSCO Medical Review Board Mary-Beth Seymour, RN  Last Updated: 3/5/2019