Dogs are typically pregnant for 62 days, plus or minus 2 days. The pregnancy is divided into trimesters, and a healthy, well- fed dog will gain about 15-20% beyond her weight at breeding. Overfeeding can result in obesity at the end of pregnancy, increasing the risk for difficult or prolonged labor and extra stress on the puppies. Conversely, underfeeding during pregnancy can result in embryo loss, abnormal fetal development, spontaneous abortion or stillbirth, small litter size, and low ...