Emergency contraception is a contraceptive method women can use after unprotected intercourse to prevent an unplanned pregnancy. Plan B only prevents pregnancy and does not cause a miscarriage or an abortion. Emergency is not the same thing as RU-486 which is used for medical abortion. It will not interrupt an already fertilized egg. Emergency contraception works in the same way as traditional birth control pills. Plan B should be used within 72 hours after the incident occurred and is available over the counter without a prescription. Ella is a prescription only method that can be taken up to five days after intercourse. Emergency contraception decreases the risk of pregnancy by about 70%. The sooner you take it after unprotected intercourse the more effective it is. Side effects include nausea, vomiting, headache, breast tenderness, abdominal pain, dizziness, and fatigue. Those side effects will subside within 1-2 days after treatment. Plan B can cause menstrual changes including spotting, initiation of menses with heavy bleeding, increased duration of a woman’s cycle and altered timing of the next menstrual period. It is available over the counter for a woman of any age.