Birth Control Pills

Helping Hand Logo

Combination oral contraceptive pills (“The Pill”, Picture 1) are a form of daily birth control that has the hormones estrogen and progestin. These are like the hormones made naturally in your body.  Pills prevent pregnancy by stopping the egg from being released from the ovary. Pills also change the mucus at the cervix to help keep sperm from reaching an egg.

Advantages of the pills

taking birth control with food

  • 91 percent effective with typical use
  • Lighter menstrual periods
  • Regular periods
  • May improve PMS (premenstrual syndrome)
  • Can improve acne
  • Can decrease risk of uterine and ovarian cancer

Disadvantages of the pills

  • Side effects include: breast tenderness, nausea, irregular bleeding, headaches and mood changes. Most of these symptoms improve with time.
  • Birth control pills may interact with certain antibiotics, anti-seizure and HIV medicines.

How to use them

  • It is important to take your pill at the same time every day. Take the pills in the order they are labeled: 3 weeks of hormone pills, then 1 week of hormone-free pills, also called the interval week.
  • If one hormonal pill is late (less than 24 hours since a pill should have been taken) or missed (24 to 48 hours since the pill should have been taken): take the late or missed pill as soon as you can. Take the rest of the pills at the usual time even if it means taking two pills on the same day.  Emergency contraception (EC) is not usually needed but can be considered if you missed the hormonal pills earlier in the cycle, or in the last week of the previous cycle.
  • If two or more hormonal pills have been missed in a row (more than 48 hours since a pill should have been taken), take the most recent missed pill as soon as possible. Continue to take the rest of the pills at the usual time even if it means taking two pills on the same day.  Use back-up contraception, like condoms, or avoid sex until hormonal pills have been taken for one week.
  • If pills were missed in the last week of hormonal pills, skip the hormone-free pills by finishing the hormonal pills in the current pack. Skip the hormone-free pills, and start a new pack the next day.  If you cannot start a new pack right away, use back-up contraception, like condoms, or avoid sex until you have taken hormonal pills from a new pack for 1 week.  EC should be considered if hormonal pills were missed during the first week of a cycle and unprotected sex happened in the last 5 days.


  • Blood clots: Pills can increase the risk of having a stroke or heart attack.  Blood clots can develop in veins (deep vein thrombosis) and in the lungs (pulmonary embolism). These conditions are rare, but can be life‐threatening.
  • High blood pressure: Pills can slightly increase your blood pressure.  For most women, this increase is small and does not affect one’s health.

Who cannot use them

Birth control pills should not be used by women who have:

  • High blood pressure
  • A blood clotting disorder
  • A history of a blood clot, stroke, or heart disease
  • Liver disease
  • Certain types of migraine headaches
  • Had a baby within the last three weeks

Tell your health care provider if you have any of these risk factors or conditions, or any other medical concerns.

When to call the doctor

Call the doctor or health care provider right away if you:

  • Miss a period or are late in starting your period
  • Think you are pregnant
  • Think you might have a sexually transmitted infection (STI)
  • Have new or worsening headaches
  • Have depression or change in mood

When to go to the emergency room

  • Sudden change in vision
  • Severe headache
  • Unusual pain in your chest
  • Difficulty breathing or speaking
  • Weakness or numbness
  • Unusual pain or swelling in the legs
  • Trouble breathing
  • Trouble speaking

Preventing STIs

The pill does not protect against sexually transmitted infections (STIs).  Condoms are the best way for sexually active people to reduce the risk of infection.  Always use a condom when you have sex.  Get yearly health check-ups, including testing for STIs.

Birth Control Pills (PDF)

HH-IV-3 10/77, Revised 12/17 Copyright 1977 Nationwide Children’s Hospital