Dogs are pregnant for about 63 days or 9 weeks, according to WebMD.com. The breed of dog does not affect the length of pregnancy. There is some individual variation, so the gestation period typically runs between 58 and 68 days.
During the first month of pregnancy, a dog exhibits few indications that it is pregnant. It gains a little weight, and some dogs experience morning sickness. Early in their pregnancy, dogs sometimes have limited appetite and energy. After a month, a veterinarian is able to identify a pregnancy by palpitating the dog's abdomen. By the 40th day, the dog's nipples are dark and enlarged, and it shows obvious weight gain. During the final two weeks, the puppies' movements are noticeable.