5w6d-one sac smaller than the other?

[katina128]

Yeah, I know it's very common. We didn't expect to see one at all, but got lucky and caught just a flicker of Baby A. He/she still was too small to even measure. We couldn't make out much in Baby B's sac b/c it was smaller, and more oblong looking. It looked like baby was right in the middle of it, to me. The tech didn't linger and couldn't get a clear shot. Their u/s machine doesn't seem very good to me. LOL