Any device or technique used to prevent unwanted pregnancy. Forms of contraception include birth control pills, male and female condoms, birth control patches, diaphragms, spermicides, interuterine devices (IUDs), and even surgeries such as vasectomies. Some methods are more effective than others.

Several forms of contraception also protect against sexually transmitted infections (STIs). Condoms are the most common example of a contraceptive that can prevent STI transmission when used properly. However, products can be marketed as “”contraceptives”” if they reduce users’ chances of pregnancy, regardless of whether or not they prevent STIs.