Birth Control Methods: How Well Do They Work?

Some Methods Work Better Than Others

Some birth control methods work better than others. The chart on the following page compares how well different birth control methods work.
The most effective way to prevent pregnancy is abstinence. However, within the first year of committing to abstinence, many couples become pregnant because they have sex anyway but don't use protection. So it's a good idea even for people who don't plan to have sex to be informed about birth control.
Couples who do have sex need to use birth control properly and every time to prevent pregnancy. For example, the chart below shows that the birth control pill can be effective in preventing pregnancy. But if a girl forgets to take her birth control pills, then this is not an effective method for her. Condoms can be an effective way to prevent pregnancy, too. But if a guy forgets to use a condom or doesn't use it correctly, then it's not an effective way for him to prevent pregnancy.
For every 100 couples using each type of birth control, the chart shows how many of these couples will get pregnant within a year. The information shown is for all couples, not just teenage couples. Some birth control methods may be less effective for teen users. For example, teenage girls who use fertility awareness (also called the rhythm method) may have an even greater chance of getting pregnant than adult women because their bodies have not yet settled into a regular menstrual cycle.
We list the effectiveness of different birth control methods based on their typical use rates. Typical use refers to how the average person uses that method of birth control (compared to "perfect" use, which means no mistakes are made in using that method).
For us to consider a birth control method completely effective, no couples will become pregnant while using that method. Very effective means that between 1 and 2 out of 100 couples become pregnant while using that method. Effective means that 2 to 12 out of 100 couples become pregnant while using that method. Moderately effective means that 13 to 20 out of 100 couples become pregnant while using that method. Less effective means that 21 to 40 out of 100 couples become pregnant while using that method. And not effective means that more than 40 out of 100 couples become pregnant while using that method.
In addition to preventing pregnancy, abstinence and condoms provide some protection against sexually transmitted diseases (STDs). However, most other birth control methods do not provide much protection against STDs, so condoms should also be used.