There is a blood test that can show if a bitch is pregnant or not. I have only done it after 28 days but probably had that time in my head because of ultrasound after the 28 days. The blood test took about 5 minutes in the surgery to get a result, the vet is satisfied with its accuracy and the cost was a lot less than ultrasound. I have had a false negative on ultrasound, missed a single pup, Had it been found we would have had a caesar, as it was we lost the pup from a very special girl. I haven't been able to get her in whelp since. Gablehaus