My hCG levels jumped up dramatically over a short time and are reading way higher than they should be for how far along I am. My OB brought up the possibility of multiples. My first U/S showed the gestational sac but nothing else as I was only 5 weeks. I go back next Thursday and I will be 7 weeks 5 days. My questions is this; if it is multiples what are the chances I'm going to know at my upcoming u/s? And has anyone been told there was one only to find out there were multiples later on? Thanks!!