The main role of condoms is to prevent pregnancy and also to reduce STDs. There are many methods of contraception, commonly used is the condom, you can also wear a ring or oral short-acting contraceptive pills, if the emergency can be taken oral emergency contraceptive pills and so on. The emergency contraceptive pill may cause abnormal vaginal bleeding and other uncomfortable symptoms, the emergency contraceptive pill may cause endocrine abnormalities and increase the risk of ectopic pregnancy, the short-acting contraceptive pill requires good self-control and requires that the drug be taken every day for 21 days to avoid omission, otherwise the drug will not be effective and will cause abnormal bleeding. The condom is generally less adverse reactions, and the full effect of condom birth control is still good, and can also reduce the occurrence of sexually transmitted diseases.