The risk of pregnancy or catching an STD may outweigh the pleasure you get from sex. The only way to make sure you don't get pregnant, get someone pregnant or get an STD is to not have sex at all. Barrier methods include condoms, the diaphragm and the cervical cap. These methods prevent pregnancy by blocking sperm from getting into the uterus. You have to remember to use them every time you have sex.
Condoms offer the most protection against STDs.
You can increase your protection by using a spermicide too. Spermicide comes as a foam, jelly or cream and kills sperm and some germs that can cause STDs. Condoms aren't expensive and they are widely available. Condoms are an especially good choice if you or your partner are having sex with other people or if either of you has had sex with other people in the past. Female condoms aren't as effective as male condoms, but they may be a good choice if a man won't use a male condom.