Understanding Emergency Contraception & Pregnancy Timeline

Question
how long after unprotected sex till pregnancy occurs (sperm to egg), and are there any alternatives to prescription EC

Answer
Usually, the sperm will get to the egg (for fertilization) within a few minutes. Once fertilization occurs, the fertilized egg travels back to the uterus (within 8 days) and it implants. YOu would start to feel symptoms of pregnancy almost immediately (nausea, fatigue, breast tenderness). A pregnancy test will not show a positive result until 14-21 days after conception. EC MUST be taken within 72 hours of the sexual act to be effective. At the present time, it is only given by prescription, but I know of no gyn who would refuse writing a prescription for it.