Went for a scan today at based on my LMP would make me 8 weeks 6 days. The doctor performed a transvaginal ultrasound and said I was showing 5 weeks. The doctor feels maybe my dates are off or I ovulated later than I thought. I had a miscarriage in January so he feels we may not know my cycle length at this point. Has anyone measured behind and gone on to have a healthy pregnancy? I have to go back next week for another ultrasound.