Pregnancy Testing – Dogs & Cats

There are several methods of diagnosing pregnancy in cats and dogs (and other pet species) but our preferred method is with ultrasound as this is the most reliable method.

  • Abdominal palpation:  it may be possible to feel the pups/kittens in the abdomen after day 30 of pregnancy but this is a very unreliable method especially in animals with large abdomens. Pregnancy diagnosed by this method should always be confirmed by another method.
  • Relaxin blood test: This test is useful for early detection of pregnancy at day 21-28 but can be unreliable in that it sometimes gives a negative result when the animal is actually pregnant. A negative result should be confirmed by another test.
  • Abdominal ultrasound : This is our preferred method. Pregnancy can be detected as early as 21 days of pregnancy but it is much more accurate to perform the ultrasound examination at day 28-30. Ultrasound cannot be used to accurately count the number of foetuses. The only way to determine an accurate count is with an x-ray
  • Abdominal x-ray: The puppy or kitten skeleton does not become calcified until late in pregnancy so diagnosis of pregnancy with an x-ray can only be done after about day 45-50. For an accurate count of the number of foetuses you need to wait until day 55. An abdominal x-ray is the only reliable method of counting the number of foetuses.