What can be seen on ultrasound scan 3 weeks after conception?
To be honest, everything is still under way at this point. The amniotic sac, and the placenta aren’t fully formed yet, and the embryo is only the size of a sesame seed. The heart is beating, but it’s still too tiny to be heard. You should have an internal scan, as nothing interesting will be picked up on a trans abdominal one.. Good luck.
