Questions and Answers: Birth Control Pills
This page has been automatically translated from English. MSDH has not reviewed this translation and is not responsible for any inaccuracies.
About birth control pills
- Birth control pills are about 98 percent effective at preventing pregnancy. They have been in use for over 40 years.
- The most commonly used pills combine two hormones, estrogen and progestin.
- Birth control pills are considered quite safe, but they do have some side effects to be aware of.
Side effects of birth control pills
- The most common negative side effects include nausea, breast tenderness, and sometimes fluid retention with weight gain.
- Some women may develop depression or an increase in blood pressure, which goes away when the pill is stopped.
- Although birth control pills usually make menstrual cycles more regular, some women do have more irregular bleeding on oral contraceptives.
- In rare cases, side effects include an increased risk of blood clots, heart attacks and strokes in some women. These risks are greatly increased in women who smoke.
- On the other hand, medical benefits include a decrease in ovarian cancer and uterine cancer and a decrease in ovarian cysts. Birth control pills may also increase bone density and help raise the HDL, or "good" cholesterol.
Who should not take birth control pills
- Women who have had a heart attack, stroke, or blood clots in the past should not take birth control pills that contain estrogen. Estrogen has been associated with increased risk of blood clots.
- Women over age 35 who smoke should also avoid the combined hormone pills that contain estrogen.
- Since some breast cancers are sensitive to estrogen, many doctors will avoid the combined hormone pills in women who have a history of breast cancer.
- Women who see flashes of light or spots with their migraines are at increased risk of stroke when taking estrogen.
- There are progestin-only pills that are often an option when estrogen needs to be avoided for some reason.
- The Depo Provera shot – a 3-month contraceptive injection – also provides contraception without the estrogen.
What to watch for if you're taking birth control pills
- Antibiotics and anti-seizure medicines can decrease the effectiveness of birth control pills.
- Alternate methods of contraception should be used while taking antibiotics.
- Contact your doctor immediately if you develop any symptoms suggestive of blood clots or heart attack, such as chest pain, blurred vision or blindness, severe leg pain especially in the calf or thigh, or severe headache.
Get health alerts and our free newsletter by e-mail:
Last reviewed on May 9, 2016