Dog - Pregnancy Testing
Traditional pregnancy diagnosis in the bitch depended on abdominal palpation (feeling for foetuses through the abdominal wall). Irrespective of the experience of the person involved, ultimately the results depend upon the state of relaxation of the bitch. Therefore, although we will carry out this procedure we will probably suggest that the bitch is scanned (i.e. undergoes ultrasonography) in order to confirm any pregnancy. Please see handout on Diagnostic imaging.
What does ultrasonography involve?
Ultrasound scanning is a relatively simple procedure to carry out, is non-invasive and does not require very much time. The majority of bitches will allow the procedure to be carried out without any sedation.
Are there any disadvantages?
In long haired dogs it may be necessary to clip some of the coat.
How soon after mating can it be carried out?
Ideally it is most accurate if performed at least 25 days following the last mating. In other words, at around the same time as we would normally palpate the bitch to see if she is pregnant.
Are there any alternatives to detect pregnancy?
Radiographs (x-rays) can be taken but are not as accurate as an ultrasound scan and cannot detect whether the puppies are alive at the time.
A blood test is also available which detects relaxin, a hormone produced by the developing placenta in the womb. This can be detected in the blood of most bitches as early as 22-27 days after the last mating. Levels of relaxin remain elevated throughout pregnancy in the bitch but decline rapidly following the separation of the placenta at parturition (birth).
Will this test differentiate between pregnancy and phantom pregnancy?
True pregnancy can be quite difficult to differentiate from phantom pregnancy in some bitches. During pseudo-pregnancy there is no placental development and so no relaxin is produced. Therefore the blood test will be negative and it can be more reliably assumed that the bitch may be exhibiting all the signs of pregnancy, including lactaton, bed making, etc but is not pregnant.
Are these results accurate?
None of these tests can be guaranteed to be 100% accurate, but ultrasound scanning and blood tests to detect relaxin are probably the most reliable. We will be happy to discuss the various methods available should you wish.
© Copyright 2025 LifeLearn Inc. Used and/or modified with permission under license. This content written by LifeLearn Animal Health (LifeLearn Inc.) is licensed to this practice for the personal use of our clients. Any copying, printing or further distribution is prohibited without the express written consent of LifeLearn. This content does not contain all available information for any referenced medications and has not been reviewed by the FDA Center for Veterinary Medicine, or Health Canada Veterinary Drugs Directorate. This content may help answer commonly asked questions, but is not a substitute for medical advice, or a proper consultation and/or clinical examination of your pet by a veterinarian. Please contact your veterinarian if you have any questions or concerns about your pet’s health. Created on Jun 24, 2008.
