How early on can you see that the baby is OK with a scan? My periods were messed before I got a BFP so at most I will be 12 weeks on the day of the scan but if I was only 3 weeks (1 week past conception) when I got the BFP I would only be 8 weeks. Is 8 weeks too soon to see a viable heartbeat? The MW said she would rather overestimate dates than underestimate as I can always go back later when needed. Any ideas? Thanks.