the only time i have heard of this is when the bitch has contracted pyometra has she got a discharge? and did the vet check her over? dont want to scare you, cos if the vet checked her she should be ok, but just keep a close eye on her and any signs of something you are not sure about go straight to the vet. but then it could have just been a bit early to see them on a scan, good luck and let us now what happens

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