A pit bull pregnancy lasts about 63 days, but it can take anywhere from 58 to 71 days. A pit bull pregnancy that lasts 72 days or more is not normal, thus a veterinarian usually induces labor.
Signs of pregnancy occur about three weeks into pregnancy, with possible nausea and loss of appetite. At that point, a veterinarian can confirm the pregnancy with an ultrasound. A veterinarian can also confirm pregnancy with a blood test around 30 days after the female pit bull is bred. At about 45 days, the puppies can be counted using a radiograph. Female dogs typically don't need assistance delivery puppies.