How long after a dog mates will she have puppies? Asked By: Orville Leannon. Date created: Tue, Jun 1, 2021 5:23 AM. Best answers. Pregnancy in dogs, also called the gestation period, normally ranges from 57-65 days with an average of 63 days. With a planned breeding, you should record the exact date of mating. If there are two matings, make a ...