Which Method of Birth Control Is Best?

The answer to that question depends on your definition of "best." Your choice of birth control depends on factors such as your health, how often you engage in sexual activity, number of partners, and whether you want children in the future. No contraceptive method is 100 percent effective against pregnancy or disease. The only 100 percent effective guarantee is abstinence (not having intercourse).
The only method of birth control that can prevent the transmission of sexually transmitted diseases (STDs), including HIV is the condom and even condoms are not 100 percent effective against STDs. Contraception effectiveness rates for preventing pregnancy vary greatly depending on the method used.