Typical use refers to the use of a given contraceptive in a way that is characteristic of how people will use it in real life. The term is used by researchers to describe a contraceptive's failure rate over the course of a year as compared to perfect use, where the contraceptive is used exactly as prescribed or indicated every single time.
Contraceptives are most effective at preventing pregnancy when they are used exactly as indicated. For example, condoms are 98% effective against pregnancy under perfect use conditions, but only 85% effective under typical use conditions. That said, even typical use rates for many forms of contraception are quite high. While perfect use is unrealistic for many people, everyone can increase the effectiveness of their chosen form of contraception by aiming to use it properly each and every time they use it.
More About Typical Use
Achieving perfect use is difficult with any contraceptive. It requires an understanding of how to use the contraceptive, then following these instructions each and every time it is used. Typical use, therefore, better reflects how well a contraceptive works in real-world conditions, when being used by people who may not use it correctly or forget to use it occasionally.
That said, the gap between perfect use and typical use varies widely between different forms of contraception. For example, forms of contraception that are more likely to be used incorrectly or inconsistently, such as withdrawal, condoms and birth control pills, have a larger gap between perfect use and typical use. Contraceptive methods that are more foolproof may have little or no gap between perfect-use and typical-use failure rates. These methods include contraceptive implants and IUDs.
When choosing a contraceptive method, it is important to consider the typical use pregnancy rate, not just the perfect use one. Then consider your own lifestyle and habits to determine whether it is the right contraceptive for you. If you feel the typical use pregnancy rate is too low and believe you are likely to make mistakes with your contraceptive, you may prefer a long-acting reversible birth control method with a much higher typical use failure rate.