@gattacinza I know breastfed babies can go up to 8 days without pooping and it's normal, I'm going to assume that it's similar for formula fed and so long as she is eating, peeing, and not in distress she is ok.
@augustcomposure It's reassuring that the blood tests didn't pick up anything amiss. The anatomy scan will help find things, many of which are fixable and curable.