Diseases & Conditions

Birth Control Pills - Oral Contraceptives


Birth Control Pills

Oral contraceptives, or OCPs, are medicines that are taken to prevent pregnancy. They are the most widely used methods of reversible birth control. OCPs work by preventing the ovaries from releasing eggs.

What is the information for this topic?

Most OCPs use a combination of the hormones estrogen and progesterone. The woman takes an OCP for 21 to 25 days. She then takes inactive pills until day 28. Inactive pills do not contain hormones. Some products include iron in the inactive pills. Most women begin their periods 2 or 3 days after they begin the inactive pills.

Some women may be told by their healthcare providers to take OCPs continuously without any inactive pills. This may be helpful for women who have moderate to severe premenstrual syndrome. It can also be helpful in treating migraine headaches.

Uses of oral contraceptives

The most common uses of oral contraceptives are:

  • decreasing premenstrual symptoms
  • preventing pregnancy
  • regulating the menstrual cycle
  • treating acne
  • treating dysfunctional uterine bleeding
  • OCPs do not prevent sexually transmitted diseases, or STDs. Safer sex practices, such as using condoms along with the pill, can help prevent STDs.

    Effectiveness

    While a woman is on OCPs, the brain no longer signals the ovaries to produce an egg each month. OCPs have a failure rate of 2% to 3% and even less when taken exactly as prescribed. The most common reasons for failure are:

  • forgetting to take the pill at the same time every day
  • poor absorption of the pill from the stomach into the bloodstream, which can be caused by diarrhea, vomiting, and the use of some antibiotics
  • taking OCPs with other medicines that may make them less effective, such as carbamazepine, phenytoin, phenobarbital, and rifampin
  • using OCPs that have expired dates
  • Contraindications

    Oral contraceptives should not be used by women who have had:

  • deep venous thrombosis or pulmonary embolus
  • breast cancer
  • cancer of the uterus
  • certain heart disorders
  • impaired liver function, such as cirrhosis
  • unexplained vaginal bleeding between periods
  • Smoking, uncontrolled high blood pressure or diabetes, and obesity may make the pill unsafe for a woman over 35. Prior to beginning the pill, a woman will have a physical exam. This includes a pelvic exam and Pap smear. The healthcare provider may order blood tests to check blood glucose and cholesterol levels.

    Side effects

    Side effects of taking oral contraceptives are:

  • breast tenderness, pain, and discharge
  • change in sex drive
  • depression
  • fatigue
  • headaches
  • irregular spotting or vaginal bleeding
  • leg pain, cramps, or swelling
  • mood swings
  • weight loss or weight gain
  • When a woman is started on an OCP, she is usually asked to try them for 2 to 3 months. This allows her body to adjust to the changes in hormone levels. If a woman continues to have side effects, it may be possible to change to a different OCP. It is important for a woman to discuss any side effects she may be having with her healthcare provider. Often changing to a different pill causes the side effects to subside.

    Serious complications include:

  • deep venous thrombosis or pulmonary embolus
  • gallstones
  • heart attack
  • high blood pressure
  • slight increased risk of breast cancer
  • If a woman develops any of the following side effects, she should stop her OCPs and call her healthcare provider immediately:

  • chest pain
  • leg pain
  • severe headache
  • severe stomach pain
  • swelling of one or both legs
  • visual impairments, including blurred vision or seeing bright lights