Birth Control: The Pill
What is birth control?
Also known as contraception, birth control prevents pregnancy. You have many different birth control options, including the birth control pill.
What is the birth control pill?
The birth control pill is a type of contraception that contains hormones that prevent pregnancy. People call it “the pill” because it comes in pill form. Women take the pill orally (by mouth) once a day. The pill is most effective when you take it consistently at the same time each day.
How effective is the pill?
The pill has the potential to be 99% effective at preventing pregnancy if you take it without fail — meaning you don’t forget to take the pill for even a day or two. However, taking the pill perfectly can be difficult, which is why nine out of 100 women who use the pill will have an unintended pregnancy every year. The pill is most reliable when you take it consistently at the same time each day. Being consistent helps keep hormone levels from fluctuating.
How does the birth control pill work?
Hormones in birth control pills prevent pregnancy by:
- Stopping or reducing ovulation (the release of an egg from an ovary).
- Thickening cervical mucus to keep sperm from entering the uterus.
- Thinning the lining of the uterus so that a fertilized egg is less likely to attach.
What are the types of birth control pills?
There are two different types of birth control pills. Both types contain hormones that prevent pregnancy.
- Combination pills contain estrogen and progestin.
- Progestin-only pills are also called “the minipill.” They’re better for some women, such as those who are breastfeeding or have a history of blood clots and strokes and shouldn’t take estrogen.
The pill comes in different dosing packets — from 21-day pill packs to 90-day pill packs, to even 365 days of active pills. Traditionally, depending on the brand and dose, you take at least three weeks of active pills followed by two to seven days of hormone-free (inactive) pills. This is called cyclical dosing. Most women have a menstrual period during the inactive pills. Some brands do not provide any inactive pills at all in the pack (they only supply three weeks of active pills). With the 21-day packs a woman does not take any pills for a week. During this time, you’ll have your period, similar to what happens when taking the inactive, hormone-free pills.
Some formulations offer continuous dosing, which means you do not have any inactive pills, and a woman takes an active pill daily. Alternatively, extended cycle dosing is when inactive pills or breaks in the active pill regimen only occur three to four times per year. Skipping the inactive pills prevents menstruation. Your healthcare provider can discuss the best option for you.
Does the pill prevent sexually transmitted diseases (STDs)?
No, the pill won’t protect you against sexually transmitted diseases (STDs) or infections (STIs). STDs, such as genital herpes, chlamydia and human immunodeficiency virus (HIV), are transmitted through direct sexual contact and the exchange of bodily fluids like semen. If you’re sexually active, the best way to prevent an STD is by using condoms in addition to the pill. Condoms, when used alone, are about 85% effective at preventing pregnancy. However if the pill and condoms are used together, both infection and pregnancy prevention is optimized. If you aren’t in a monogamous relationship with one partner, your healthcare provider will suggest using condoms along with the pill to prevent pregnancy and STDs.
What are benefits of taking the pill?
Some women take the pill for health purposes. The pill can:
- Regulate or lighten menstruation.
- Prevent anemia by making periods lighter or shorter.
- Lessen menstrual cramps (dysmenorrhea).
- Manage premenstrual syndrome (PMS) and premenstrual dysmorphic disorder (PMDD).
- Treat polycystic ovary syndrome (PCOS).
- Treat endometriosis or uterine fibroids.
- Lower the risk of ovarian cancer, uterine cancer and colon cancer.
- Improve acne.
- Stop unwanted hair growth.
- Reduce migraines.
- Control hot flashes during the transition into menopause.
Are there any side effects to taking the pill?
Some women experience medication side effects when they start taking the pill. These side effects often improve after a couple of months. Tell your healthcare provider if you experience side effects. You may be able to switch to a different brand that doesn’t cause problems. However, simply waiting out the symptoms for a few cycles often help resolve many of the symptoms, especially when first starting a new pill regimen. Potential side effects include:
- Breast tenderness or swelling.
- Irritability or moodiness.
- Spotting between periods (abnormal menstruation).
Are there any health risks to taking the pill?
Birth control pills are safe for most women. The pill has been available for 60 years, so there is a lot of comfort and experience with its use. A small percentage of women who take the combination (estrogen-containing) birth control pill have an increased risk for developing these rare complications:
- Blood clots.
- Deep vein thrombosis (DVT).
- Heart attack.
- Hypertension (high blood pressure).
Your doctor will talk to you about your level of risk based on your medical history. Luckily, if an individual is not able to use an estrogen-containing pill, most can still safely take progestin only pills.
How soon does the pill work?
It can take up to seven days for the pill to become effective in preventing pregnancy. During this time, you should use another form of birth control. If the pill is used to control symptoms such as acne or abnormal bleeding, it can take three to four months to see true benefits.
What should I do if I miss a pill?
Take the missed pill as soon as you remember. Then take your usual daily dose as planned. You should also use a backup form of birth control until you have your period. Call your healthcare provider if you miss several days of the pill. Your provider can discuss pregnancy test and emergency contraception options. It is helpful to keep the package inserts of the available, most will give specific instructions on what to do if there is a missed pill.
Should I avoid certain medications while taking the pill?
You should always check with your healthcare provider before taking any new medications or herbal supplements. Certain drugs can make the pill less effective and increase your chances of getting pregnant. These products include:
- Antiseizure medications.
- Herbal supplements, such as St. John’s wort.
- Medications used to treat HIV.
Can I take the pill while breastfeeding?
The combination birth control pill contains estrogen, which can decrease milk production. If you are breastfeeding, your healthcare provider may recommend taking the progestin-only pill instead. However, some women may use estrogen-containing pills once milk supply is fully established, and a woman’s risk of blood clots is minimized.
What are alternatives to the pill?
If you’re not confident you can remember to take a daily pill, talk to your healthcare provider about these other birth control options:
- Etonogestrel implant (Nexplanon®).
- Intrauterine device (IUD), several hormonal and nonhormonal options are available.
- Removable contraceptive vaginal ring (both monthly and yearly options are available).
- Skin patches (Xulane®).
- Depo-Provera® progestin injection (also called Depo).
A note from Cleveland Clinic
The birth control pill is a highly effective way to prevent pregnancy when you take it consistently every day. The pill can also lower your risk of certain problems, such as uterine and ovarian cancers, migraines, and acne. Some women experience medication side effects like nausea, though this is usually temporary. You may need to try several different brands of the pill before finding the one that works best for you. Talk to your healthcare provider if you have questions or concerns about the pill.
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