Yes it is normal for pregnant cats to have diarrhea. It can be caused by many things, whether it's her changing hormones, a change in her diet (If your switching her onto kitten food), or even just the fact that her unborn growing kittens are pushing on her bowels. If her diarrhea persists for more then 48 hours or she appears to be acting lethargic, contact your vet.
Its possible if the cat has anxieties or any type of virus at the time she is ready to birth her kittens
My cats pregnant and has diarrhea,is that normal?
Diarrhea before delivery of puppies is not common and does not affect all dogs. But it can be due to stress/anxiety of labor. Diarrhea in dogs should not be ignored at any time in pregnant or non pregnant dogs because it can be due to serious underlying cause and may lead to dehydration. So, it is better to get advice from the vet.
No hope you took them to the vet
It is not normal for the pregnant animals to have diarrhea. Without wasting any time, take it to your vet as soon as possible. For further assistance please visit this link