A dog's pregnancy lasts on average 63 days (9 weeks) from the mating date. The range is 58 to 68 days. Smaller breeds tend toward shorter, larger breeds toward longer gestation periods.

There are few visible signs in the first 3 weeks. From week 4, nausea, enlarged nipples, and slight weight gain may appear. From week 5, the belly is visibly enlarged. An ultrasound from day 25 provides certainty.

For the first 5 weeks, maintain normal food and moderate exercise. From week 6, increase food energy content by 25-50%. In the last week, prepare a quiet whelping area and monitor temperature (a drop below 37°C signals imminent birth).