Rose is correct. Their heat cycles stay the same regardless of wether they've had a litter or not. She may have had a "silent heat". You wouldn't have noticed any signs. And it's possible that your male did get to her if you were away from them and it could go unnoticed. Or, it could also be a false pregnancy. Either way, you'll need to have a vet confirm it.
I'm sure you realize this, but if you aren't planning on breeding your male, get him neutered asap!
__________________ Steph, Mama to 6 skin babies and beautiful yorkies! |