Birth control pills are oral medications used to prevent pregnancy.
More than 80 percent of sexually experienced American women have used birth control pills, according to research from the Centers for Disease Control and Prevention (CDC). “The pill” is very popular and highly effective at preventing pregnancy. The CDC found that out of 100 women using the pill, nine became pregnant in a 12-month period of using it, giving the pill a 9 percent failure rate. Birth control pills are also known as oral contraceptives.
Combined hormonal contraceptives work by preventing ovulation and thickening cervical mucus to keep sperm from entering the uterus.
“The minipill,” which contains progesterone only, works primarily by thickening cervical mucus and thinning the endometrium. It may also prevent ovulation.
There are two types of birth control pills: combination pills and progestin-only pills. Combination pills contain synthetic forms of the hormones estrogen and progestin. Progestin-only pills do not contain estrogen. Progestin-only pills are also called “the minipill.”
Women have a number of options when choosing birth control pills. There are several types of combination pills:
- monophasic pills give you the same dose of hormone every active day in the cycle
- multiphasic pills provide different levels of hormones during the cycle
- extended regimens are designed to provide contraception and decrease frequency of menstrual bleeding
In addition, the minipill is a type of progestin-only pill that is suitable for women who are not able to take in additional estrogen for medical or other reasons.
Not every type of pill is appropriate for every woman. Talk to your doctor about which pill option would work best for you. Factors that can affect pill choice include:
- menstrual symptoms
- whether you are breastfeeding
- cardiovascular health
- other chronic health conditions
- use of certain medications
You need a prescription to use birth control pills. Visit your doctor or a healthcare clinic to discuss what type of birth control is right for you.
Combination pills come in a variety of schedules, including monthly packs, where you might have 21-, 24-, or 28-day cycles, or extended regimens like 91-day cycles. One pill is taken each day at the same time of day. The pills that are specially marked or different colors usually do not contain hormones (placebos), depending on the brand and type of pill. You take them to help you stay on a pill-taking routine. You will get your period during the week you are not taking hormones.
Progestin-only pills come in packs of 28. You must take one pill at the same time every day. There are no placebos in packages of the minipill. All progestin-only pills contain hormones.
If taken correctly, birth control pills are extremely effective in preventing pregnancy. According to Planned Parenthood, the failure rate is less than 1 percent if always taken properly and 9 percent if the pill is not always taken daily as directed.
Progestin pills must be taken within the same three-hour time period every day to be fully effective. There is slightly more flexibility with combination pills.
Certain medications may make the pill less effective. These include:
- rifampin (an antibiotic)
- certain oral yeast infection medications
- certain HIV medicines
- certain antiseizure medicines
- St. John's wort
The pill may also be less effective if you have diarrhea or are vomiting. Check with your doctor to see if you are at risk after a stomach illness. Use backup methods of contraception until you know it is safe not to.
Birth control pills have a number of benefits. They are:
- able to regulate the menstrual cycle
- fully reversible
Combination pills may also offer some protection against:
- ectopic pregnancy
- bone thinning
- non-cancerous breast growths
- endometrial and ovarian cancer
- heavy periods
- severe menstrual cramps
Birth control pills do not protect against sexually transmitted infections. To ensure protection against sexually transmitted infections, it is necessary to use condoms as well.
If a woman delays starting a new pack of pills after finishing one cycle, the risk of pregnancy increases. Women have to be diligent about picking up a new pack on time.
Every woman reacts differently to the hormones in birth control pills. Some women experience side effects, such as:
- decreased sex drive
- bleeding between periods
- breast tenderness
These effects usually improve after a few months. If they do not, talk to your doctor about whether you might do better on a different pill.
There are multiple risks associated with birth control pills. One serious complication associated with combined hormonal contraceptive use is an increased risk of blood clotting. This can lead to:
- deep vein thrombosis
- heart attack
- pulmonary embolism
Overall, the risk of a blood clot is low. According to the American Congress of Obstetricians and Gynecologists, out of 10,000 women, only about six to nine women will develop a blood clot after taking the pill for a year. This is still lower than a woman’s risk of developing a blood clot during pregnancy and immediately post-partum. However, the risk is higher for certain women. This includes women who are:
- very overweight
- suffering from high blood pressure
- on bed rest for long periods
Talk to your doctor about your risk factors and whether the pill is a good birth control option for you.