Condoms are the only birth control that reduces your risk of both pregnancy and STDs, including HIV. But, in order to work, condoms must be used correctly and must be used every time you have sex. It’s important to know, however, that they cannot completely protect you and your partner from some STDs, like herpes, syphilis, or human papillomavirus (HPV), the virus that causes genital warts and cervical cancer. Also, condoms can break, slip, or leak, especially if they are not put on and taken off properly.