1st ultrasound i measured 4wks 6 days. 13 days later i only measured 6 weeks 1 day. there was a fetal pole, but no heart beat. should i worry about possible miscarriage or could i just be to early for heartbeat. i go back in 7 days for another us. ?

Scanning so early...: One's Ob-Gyn doctor can help with such concerns because normally women don't need to get scanned so early. Perhaps this is a special situation, which is why one's doctor can help with this. In general, many early pregnancies miscarry as a normal part of human life. The early embryos that progress successfully on their own... those are the ones that become babies.