A female dog normally begins delivering her puppies within six to 24 hours of beginning labor. She may take up to two hours of active labor to deliver each puppy and may rest for up to four hours between puppies. Labor ends with delivery of the placentas.
About 24 hours before labor begins, a dog's body temperature drops by 2 or 3 degrees. She signals the onset of labor by restless, anxious behavior and looking for a place to make a nest. At the end of Stage I, her cervix is fully dilated. Stage II is the process of pushing a puppy out and should take no more than two hours. After a puppy is delivered, the mother may go into Stage III labor and deliver the puppy's placenta or may quickly deliver more puppies and push their placentas out afterward.