
Sadly this did happen to my bitch back in the summer. She had previously whelped a healthy litter of 7 pups ! Around day 27 she started passing small clots in her wee, by day 29 it looked like she was back in season, bleeding quite heavily. My vet, like yours, put her on a course of anti-biotics which seemed to help. By day 35 she had stopped bleeding and I thought all was well. Sadly it was not to be, we had her scanned again around 7 weeks and the whole litter had died. She actually started delivery her dead babies, which were very small and black, my vet said they looked as though they had died around the 5 week stage. We had her scanned just before 5 weeks and saw 8 very lively pups :-(
I really hope that all goes well for your girl, I had lots of e-mails from people on here, a lot of them telling me that their girls had bled and they still went on to have a healthy litter at the end of it. I know exactly how you are feeling, my girl has been mated again and I am a complete paranoid wreck at the moment (I'm not advertising here either I have a waiting list as long as my arm) but so far so good.
I will keep everything crossed for you and hope you get a lovely healthy litter!
Good luck!
Sharon