Barrier methods for preventing pregnancy include condoms, diaphragms, and cervical caps that block sperm from reaching an egg. External condoms, commonly known as male condoms, are thin pouches made of latex, plastic (non-latex), or lambskin, which cover the penis during sex. External condoms are 98% effective at preventing pregnancy when used perfectly and 87% effective with typical use. Synthetic (latex or plastic) condoms also protect against STIs. Internal condoms, commonly known as female condoms, are soft plastic pouches inserted into the vagina up to eight hours before sex to create a barrier between the sperm and egg. Internal condoms are 95% effective at preventing pregnancy when used perfectly and 79% effective with typical use. Internal condoms also protect against STIs.
A diaphragm is a soft silicone cup, shaped like a dish, which is inserted into the vagina to cover the cervix. Diaphragms are most effective when used in conjunction with spermicide, a cream or gel that kills sperm. They are 94% effective with perfect use and 85% effective with typical use.
Like a diaphragm, a cervical cap is a reusable, soft silicone cup that is inserted into the vagina to cover the cervix. Cervical caps are smaller than diaphragms, shaped like a thimble, and can be left inside the vagina up to two days (48 hours) after sex. Cervical caps are more effective (86% with typical use) for users who have never given birth than those who have (71% with typical use).