
We had, supposedly, unconfirmed, this happen at 5 weeks with one of our bitches. Up to then my bitch was as to be expected, getting thicker through her flanks. But from that point in her pregnancy, she didn't get any bigger. In the end she had 1 big bitch puppy, by C.Section. There was however, no indication that there had been others so Im not sure whether she did reabsorb. She wasn't the most prolific producer - 2 puppies in her first litter and the singleton in her second and final litter. I don't do scans so wasn't able to know whether she was carrying more at some point.
I have to say even if I did scan and nothing showed up, I'd always be watching, at the due date! We never had a pyo with any of our bitches, thankfully, but I'd be very concerned about what might be going on with your bitch, especially if she had a closed pyo. I think, once she's past her due date, I'd get her in for a check - if she is going to have a false pregnancy, lactate etc., then she will probably need help to scatter any milk she's producing. This is going to be distressing for her, even if there's no sign of pyo. Might be as well in any case, to get her spayed in another couple of months.