Following the contractions and passage through your very narrow birth canal, the baby will display the following characteristics: (americanpregnancy.org)
The puppies» large heads, coupled with the mother's narrow birth canals make a natural birth almost impossible, and a breached puppy could cause loss of both the mom and the puppies. (blog.pawedin.com)
Small birth canal: some women have a narrow birth canal, which could make natural birth very difficult and uncomfortable. (medic8.com)