Having had a dog give birth thrice at my house before I myself had a child, taught me more about giving birth than all the books and videos on the internet, not to mention the hush-hush births I’d been around in human hospitals.
Dogs approach birth without the trained tension and worry humans go through.
The first time a dog in my care was pregnant, she got a terrible stomach infection and couldn’t keep anything in. I dutifully took her to a vet, “just to be on the safe side”. The vet ordered an xray.