I always have & always will have my girls x-rayed about a week before they are due for the peace of mind of knowing (or at least having a very good idea) of how many pups to expect and/or having a good idea whether to expect any possible problems with the whelp. Even x-rays done in that last week of pregnancy are not always 100% accurate, but still they are extremely helpful in my opinion. I've had ultrasounds done before in about the 3rd or 4th week before, but only to confirm pregnancy when I just "had to know". Not anymore......I've learned to be patient.