The type of birth control you use is a personal decision, and there are many options to choose from. If you’re a sexually active female, you may consider birth control pills.

Birth control pills, also called oral contraceptives, are medications you take by mouth to prevent pregnancy. They’re an effective method of birth control. Find out how they work and what side effects they can cause, as well as other factors to help you decide if birth control pills are a good choice for you.

Check out a visual guide of how birth control affects your body »

Combination pills

Combination pills contain synthetic (man-made) forms of the hormones estrogen and progestin. Most pills in each cycle are active, which means they contain hormones. The remaining pills are inactive, which means they don’t contain hormones. There are several types of combination pills:

  • Monophasic pills: These are used in one-month cycles and each active pill gives you the same dose of hormone. During the last week of the cycle, you take inactive pills and have your period.
  • Multiphasic pills: These are used in one-month cycles and provide different levels of hormones during the cycle. During the last week of the cycle, you take inactive pills and have your period.
  • Extended-cycle pills: These are typically used in 13-week cycles. You take active pills for 12 weeks, and during the last week of the cycle, you take inactive pills and have your period. As a result, you have your period only three to four times per year.

Examples of brand-name combination pills include:

  • Azurette
  • Beyaz
  • Enpresse
  • Estrostep Fe
  • Kariva
  • Levora
  • Loestrin
  • Natazia
  • Ocella
  • Low-Ogestrel
  • Ortho-Novum
  • Ortho Tri-Cyclen
  • Seasonale
  • Seasonique
  • Velivet
  • Yasmin
  • Yaz

Progestin-only pills

Progestin-only pills contain progestin without estrogen. This type of pill is also called the minipill. Progestin-only pills may be a good choice for women who can’t take estrogen for health or other reasons. With these progestin-only pills, all pills in the cycle are active. There are no inactive pills, so you may or may not have a period while taking progestin-only pills.

Examples of progestin-only pills include:

  • Camila
  • Errin
  • Heather
  • Jencycla
  • Nor-QD
  • Ortho Micronor

Deciding on a type of birth control pill

Not every type of pill is a good fit for every woman. Talk to your doctor about which pill option would work best for you. Factors that can affect your choice include:

  • your menstrual symptoms
  • whether you are breastfeeding
  • your cardiovascular health
  • other chronic health conditions you may have
  • other medications you may take

Combination pills work in two ways. First, they prevent your body from ovulating. This means that your ovaries won’t release an egg each month. Second, these pills cause your body to thicken your cervical mucus. This mucus is fluid around your cervix that helps sperm travel to your uterus so it can fertilize an egg. The thickened mucus helps prevent sperm from reaching the uterus.

Progestin-only pills also work in a few different ways. Mainly, they work by thickening your cervical mucus and by thinning your endometrium. Your endometrium is the lining of your uterus where an egg implants after it’s fertilized. If this lining is thinner, it’s harder for an egg to implant in it, which will prevent a pregnancy from growing. In addition, progestin-only pills may prevent ovulation.

Combination pills come in a variety of formats. These include monthly packs, which follow either 21-day, 24-day, or 28-day cycles. Extended regimens can follow 91-day cycles. For all of these formats, you take one pill each day at the same time of day.

Progestin-only pills, on the other hand, only come in packs of 28. As with combination pills, you take one pill at the same time every day.

If taken correctly, birth control pills are very effective in preventing pregnancy. According to the CDC, both the combination pill and the progestin-only pill have 9 percent failure rates with typical use. That means out of 100 women using the pill, 9 would get pregnant.

To be fully effective, progestin pills must be taken within the same three-hour time period every day.

There is slightly more flexibility with combination pills. In general, you should try to take combination pills at the same time each day, but you can take them within the same daily 12-hour window and still have pregnancy protection.

Certain medications may make either type of pill less effective. These include:

  • rifampin (an antibiotic)
  • certain HIV medications such as lopinavir and saquinavir
  • certain antiseizure medications such as carbamazepine and topiramate
  • St. John's wort

The pill may also be less effective if you have diarrhea or vomiting. If you’ve had a stomach illness, check with your doctor to see if you’re at risk of pregnancy. Use a backup method of contraception until you know it’s safe not to do so.

Birth control pills have a number of benefits:

  • They protect you 24/7. You don’t have to worry about birth control during intimacy.
  • They’re effective. They protect against pregnancy better than most other birth control options.
  • They help regulate your menstrual cycle. This can be helpful for women with irregular or heavy periods.
  • They’re fully reversible. This means when you stop taking them your cycle will return to normal and you can get pregnant later.

There are also benefits depending on the type of pill. Combination pills may also provide some protection against:

  • acne
  • ectopic pregnancy
  • thinning bones
  • non-cancerous breast growths
  • endometrial and ovarian cancer
  • anemia
  • heavy periods
  • severe menstrual cramps

Progestin-only pills have other benefits as well, such as being safer for women who:

  • can’t tolerate estrogen therapy
  • are smokers
  • are older than 35 years
  • have a history of blood clots
  • want to breastfeed

Birth control pills don’t protect against sexually transmitted infections. To make sure you’re protected against these infections, you need to use condoms in addition to your daily pill.

Also, you have to remember to take your pill every day. And you need to make sure you always have a new pack ready to go when you finish a pack. If you miss a pill or delay starting a new pack after finishing a cycle, your risk of pregnancy increases.

While birth control pills are safe for most women, they do come with some side effects and risks. Every woman reacts differently to the hormones in birth control pills. Some women have side effects, such as:

  • decreased sex drive
  • nausea
  • bleeding between periods
  • breast tenderness

If you have these side effects, they will likely improve after a few months of using the pill. If they don’t improve, talk to your doctor. They may suggest that you switch to a different type of birth control pill.

Risks

A serious risk of using birth control pills, especially combination pills, is an increased risk of blood clots. This can lead to:

Overall, the risk of a blood clot from using any kind of birth control pill is low. According to the American Congress of Obstetricians and Gynecologists, out of 10,000 women, fewer than 10 will develop a blood clot after taking a combination pill for a year. This risk is still lower than the risk of developing a blood clot during pregnancy and immediately after giving birth.

However, the risk of a blood clot from the pill is higher for certain women. This includes women who:

  • are very overweight
  • have high blood pressure
  • are on bed rest for long periods

If any of these factors apply to you, talk with your doctor about the risks of using a birth control pill.

Many birth control options are available today, and the birth control pill is an excellent one. But the best birth control choice for you depends on many factors. To find an option that works for you, talk to your doctor. Be sure to ask whatever questions you have. These might include:

  • Which type of birth control pill might be better for me?
  • Am I taking any medications that could cause problems with a birth control pill?
  • Am I at higher risk of blood clots from the pill?
  • What should I do if I forget to take a pill?
  • What other birth control options should I consider?

Q:

What other birth control options are there?

A:

Birth control pills are just one of many contraceptive options. Other options range from long-term methods such as the intrauterine device (IUD) to short-term choices such as the contraceptive sponge. To find out about these many options and their effectiveness, cost, and pros and cons, read about which birth control method is right for you.

Healthcare Website Medical TeamAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.