A dog may be pregnant if you notice signs such as increased appetite or nausea, weight gain, enlargement and darkening of nipples, swollen belly, tiredness, nesting behavior, increased affection or irritability, and sometimes vomiting early in pregnancy. However, these signs can vary and some dogs may experience false pregnancy. To confirm pregnancy accurately, a veterinarian can use diagnostic tests such as:
- Abdominal palpation (feeling the belly) around 28-30 days after mating to feel fluid-filled sacs.
- Ultrasound from around 25 to 35 days to see fetal heartbeats and estimate the number of puppies.
- Blood test measuring the hormone relaxin, produced only during pregnancy, around 25-30 days.
- X-rays from about 55 days to detect skeletons of puppies and count them.
Early signs may be subtle, so a vet's diagnostics are best to confirm pregnancy and rule out other conditions that mimic pregnancy symptoms.