You’ve read up on dog breeding, given your dog the best nutrition, and found the perfect sire, but you’ve yet to see so much as a hint of a baby bump. If this sounds like you, there’s probably one nagging question that you can’t get out of your head: “Why won’t my dog get pregnant?”
Struggling to conceive can be frustrating and emotional regardless of species, so you and your dog are probably both concerned. What’s an aspiring puppy grandparent to do?
Well, it all starts with figuring out why your dog isn’t getting pregnant. Here are the four most common reasons — and what to do about them.
Four Reasons Why Your Dog Won’t Get Pregnant
1. You Could Be Mistiming Your Dog’s Cycle
The number one reason why dogs won’t get pregnant is also the most deceptively simple: you just haven’t gotten the timing right.
A dog’s estrus, or heat, cycle has four stages. There’s proestrus, which lasts between five and 27 days, followed by estrus, which lasts four to 24 days (9 on average).
And then there’s a period of diestrus, which lasts about two months. Finally, there’s anestrus, which can last for four or more months.
This cycle repeats itself anywhere from one to three times per year, usually twice. And your dog can only get pregnant during the estrus period — after all, it’s the canine equivalent of human ovulation, when the egg is ready for the sperm.
That means that the average dog can only get pregnant 18 days out of the entire year.
Those aren’t great odds if you’re just trying at random times. So if you want your dog to get pregnant, you need to memorize the signs of canine estrus and time her cycle perfectly.
During proestrus, your dog will likely have bloody vaginal discharge. This is a good indicator that she’s about to ovulate, and the discharge will become less bloody as she enters the true estrus stage.
While in estrus, your dog may urinate more frequently, lick her genitals obsessively or hold her tail off to the side of her body. She may also be restless and behave more aggressively, especially towards other female dogs.
Watching for these behaviors will help you time your breeding just right.
But the best way to get the timing right is to enlist the help of a vet with experience in estrus timing. They’ll use special tests to check your dog’s progesterone and LH levels, both of which can reliably indicate estrus.
2. Your Dog May Have Cystic Endometrial Hyperplasia (CEH)
As your dog ages, her uterus may thicken, which makes it more difficult for fertilized eggs to implant themselves inside it. When these changes involve bacterial infection or other foreign material in the uterus, they’re known as cystic endometrial hyperplasia, or CEH.
CEH can take on several forms, and it’s not known exactly what causes it. It appears to be related to age, as its incidence skyrockets in dogs older than three years of age, but not all dogs get it.
Many experts believe that CEH is related to elevated progesterone levels. Progesterone is created during the diestrus period, so the more heat cycles a dog goes through, the more likely she is to develop CEH.
And dogs that have received estrogen or progesterone supplements are more likely to develop CEH, though the condition typically resolves itself once treatment stops.
See a vet if you suspect that your dog has CEH. Treatment is available in the form of progesterone-lowering hormones called prostaglandins, though these can have considerable side effects and don’t always work.
3. Brucellosis Could Make Your Dog Infertile
Canine brucellosis is a relatively rare disease, but it’s one of the most common causes of infertility in dogs. Caused by the bacteria Brucella canis, it’s highly contagious among dogs and can even spread to humans via bodily fluids.
Brucellosis wreaks havoc on a dog’s reproductive tissues, though it can also affect the eyes, liver, lymph nodes, spleen and spine. In male dogs, the testicles and prostate are usually affected, while in females, the uterus is at the highest risk of damage.
Dogs of both sexes often lose weight, refuse to exercise and display low energy levels.
There is no reliable cure for brucellosis. Antibiotics may work temporarily, but the infection usually comes back, and removal of the infected tissues is only somewhat effective.
It’s critical to test your dog for brucellosis before breeding her. If she does become pregnant while infected, there’s a 75% chance that the litter will spontaneously abort during the third trimester, which often kills the mother as well.
But chances are that if your dog has brucellosis, her reproductive organs are too damaged for her to conceive at all.
4. There May Be a Problem with the Male’s Semen
Even if your dog is in perfect health and you time her cycle just right, she won’t get pregnant if there’s a problem with the male dog’s semen or the insemination method.
If the male dog is older than five, the quality and quantity of his semen is likely decreased. You may need to find a different sire or, if you’re dead-set on the male you’ve chosen, breed the dogs multiple times per cycle for successful conception.
There’s also a chance that, during the breeding event, the “tie” — the period when the two dogs were locked together — didn’t last long enough. It typically lasts between two and 25 minutes, and if it’s interrupted for any reason, insemination may not occur.
And if you used artificial insemination, there are other factors to consider. If the semen was chilled or frozen, it may have been stored at an improper temperature or in an improperly-sealed container.
The insemination procedure itself may have been compromised by spermicide, a hidden ingredient in many medical lubricants and reusable equipment. If latex gloves, syringes or collection sleeves were used, the semen may have been destroyed by the latex.
This is why it’s so important to consult with an experienced professional when breeding your dog, especially if you’re opting for artificial insemination. A professional will have access to the right equipment and tests to make sure that semen quality is good and the procedure goes smoothly.