Progesterone testing is an important tool for breeders to use when managing their dogs' reproductive cycles. By measuring the progesterone in a female dog's system, breeders can determine when she will ovulate and be ready to mate.
Sometimes even the best breeders forget to be on top of timing their breedings— and timing is key! Not doing so may create issues since it's hard to tell if your dam will have any troubles later in pregnancy. Timing really can make all the difference in positive outcomes for both your dam and puppies.
But my girls get pregnant without progesterone testing
The big argument I hear is that breeders can get their dams pregnant without progesterone testing, so they don’t need it.
But there are a lot of potential problems with not accurately timing your breedings, most of which concern the safety issue of not knowing when she’s due.
Progesterone testing increases the likelihood of your dam producing a healthy number of puppies, as opposed to an unexpected single-puppy litter (singleton).
Many dams that have had a singleton pregnancy do not go into labor at the 63 day post ovulation mark.
The puppies and their placentas actually produce the hormones that initiate labor. When there are one or two puppies only, then they may not produce enough hormones to tell the dam's body to start labor. Delayed labor can result in placental deterioration and fetal death.
This can be extremely heartbreaking for breeders, as it typically results in a c-section and loss of the puppy and can be life-threatening for the dam as well if not treated immediately.
C-sections for dams can be needed for many reasons, whether it is a large litter, singleton puppies, fetal position or size issues.
Large litters cause particular trouble and the volume of puppies and their associated placentas and fluids can lead to a complicated labor and birth. Or a puppy can be born so slowly that it may become stillborn which can block other pups from the birth canal.
Getting a c-section based on ovulation (ovulation occurs at 5-6 ng/dl) as early as two days before the due date is a safe option. Without knowing the due date, sometimes your vet may not be able to save the dam and her puppies.
“Reverse” progesterone testing
When progesterone levels get down to 2ng/ml at the end of a pregnancy you should expect whelping within 24 hours. A “reverse” progesterone is testing progesterone near the due date to see when your dam will likely whelp. This can also be used to time c-sections.
However, relying only on "reverse progesterone" to determine due date is not advisable. This is because the procedure requires daily trips to the vet, which can be inconvenient and burdensome and also stressful for your dam. It exposes her to other dogs at the clinic. You also risk the possibility of your dam going into labor at night, which increases your cost for an after-hours c-section.
Also, reverse progesterone testing fails in certain cases, such as luteal insufficiency or a problematic pregnancy. And, reverse progesterone values may not drop until the placentas have deteriorated and the pup has died from placental failure, especially if there is only a small litter of puppies.
At the very least
Have a blood draw done when you breed her. Either you (if you have the capability) or your vet can spin down the blood and freeze the serum so if you need to know ovulation to predict due date you can always test the frozen sample. The risk with this is you can take your sample too far before or after ovulation for the frozen sample to provide the needed information.
But ideally—progesterone test to determine ovulation. You owe it to your dam and your puppies to do everything you can to ensure a safe whelping and healthy puppies.