Although it's the most fail-proof method of contraception, it's also the least fun. The word abstinence can mean refraining from something, e.g. abstinence from alcohol or drugs. But abstinence from sex is about as fun as watching paint dry. Various groups promoting abstinence use propaganda to get their way, such as videos of a couple having sex getting covered in horrible sores and dying in flames.
Abstinence group: Abstinence gets you into heaven! If you have sex outside of marriage, God will give you herpes, AIDS and all sorts of STDs!
Anyone with a brain: God doesn't give you herpes, unsafe sex does. Just use a fucking condom!