The options for determining pregnancy in dogs are as follows:
- Wait for all of the obvious signs, such as weight gain & lactation. However, some dogs may go through false pregnancies where they show abdominal distension and even produce milk! This is definitely not the most reliable way to tell!
- After ~22 days post-breeding, blood may be drawn to run an early pregnancy test for the hormone relaxin. This is a negative or positive test, and does not give us any additional information about the puppies.
- At ~25 to 28 days post-breeding, ultrasound can be used to detect fetal heartbeats. It may be difficult to tell exactly how many hearts are beating, but this method can still be used to help estimate litter size.
- At ~21 to 31 days post-breeding, abdominal palpation may be used to try to feel the walnut-sized fetuses. Ideal timing is to palpate at approximately 28 days. This requires skill & experience and is not the best way to estimate the number of puppies present.
- At ~45-48 days post-breeding, puppy skeletons have begun to calcify and can begin to be picked up on x-ray. This can be used to help estimate the number and size of puppies. As for any safety concerns, x-rays are commonly done in this later stage of pregancy and are considered to be relatively safe. Early pregnancy is when x-rays pose the most significant risk to unborn puppies.
We haven't yet decided what method we will used to confirm Rogue's pregnancy. We typically wait to do x-rays because this allows us to estimate the number and size of the puppies. This information helps us to make critical decisions during the labor.