I had an early pregnancy scan on Tuesday following three successive miscarriage ( a chemical pregnancy, a loss at 8 weeks and another chemical) , my lmp was 6 weeks 4 days at the time of the scan but I only measured CRL 2.4 mm which seems small for my dates, I know I ovulated on day 18 so could this be a factor ? The nurse saw a strong heartbeat and didn't seem worried about size ... am I worryingly unnecessarily ?