After having your female dog undergo surgery, the last thing you would expect is your dog going into heat after being spayed. Yet, it’s unmistakable, you dog is having a bloody discharge and swelling just weeks or months after the spay surgery, and on top of that, she is also attracting males, just like when she was going into heat. What is going on? Well, start off by taking a deep breath, you are not imagining things, dogs can go in heat after being spayed and there is a logical explanation. If you are noticing any discharge from your female dog after being spayed, it’s a good idea to call your vet and have your dog seen sooner than later, in the meanwhile, here is a quick rundown on what may be going on.
The Purpose of Spay Surgery
A dog’s spay procedure, is medically known as ovariohysterectomy.
For those interested in the origin of words, we can deduce that the word ovario derives from the Latin word ovarium meaning ovary, while the word “hyster” is the Latin word for womb. Then, we have the suffix “tomy” which means “to cut.”
Put these words together and you’ll get the surgical removal of the uterus and ovaries.
A female dog’s two ovaries are responsible for producing eggs that are meant to be fertilized. Those ovaries also secrete female hormones.
A dog’s uterus instead is meant to carry puppies. Once a dog’s eggs are fertilized, they travel to the uterus so that they can implant and start developing into puppies.
The removal of a dog’s uterus and ovaries therefore should result in a sterile dog whose body is no longer influenced by effects of hormones. Of course, if your dog was in heat at the time of the surgery, you may expect the signs of heat to persist a bit until subsiding once and for all, but in this case, we’re talking about a dog going into heat after being spayed.
After being spayed, with no more hormones such as estrogen and progesterone in circulation, spayed female dogs should therefore no longer go into heat. This should automatically translate into no more discharge, no more swelling and no more attracting male dogs.
An Exception to the Rule
After learning about what happens when a female dog is spayed, it’s pretty clear that after a dog is spayed, she shouldn’t go into heat at all, so why are some dogs going in heat after being spayed?
It’s not a very common occurrence, but it can happen once in a blue moon that the veterinarian performing the spay procedure accidentally leaves behind a bit of ovarian tissue in the dog’s abdomen.
How can this happen? Before blaming your veterinarian for being distracted on the job or lacking experience, consider that a dog’s ovaries can be tricky at times to remove. The ovary hides in a pocket of fat and sometimes a part of the ovary can be left behind because it may be very difficult to see, explains veterinarian BJ Hughes. At times, a piece of ovarian tissue may also be accidentally dropped into the dog’s abdomen during surgery. And for those wondering, this condition also has a name, it is known as ovarian remnant syndrome.
On top of an ovary hiding in a tricky area, sometimes a dog’s ovary or a part of ovarian tissue may be ectopic, meaning that it is found in an abnormal place. The presence of ectopic ovarian tissue left behind is quite a rare occurrence, but it does happen sometimes.
Regardless of whether the vet accidentally left some tissue behind or the ovary simply went missing in action, the remnant tissue is capable of secreting enough hormones that may trigger a dog to go into heat and even attract males. The good news though is that even though these dogs go into heat despite being spayed, they cannot become pregnant. With no uterus in place, there is just no way puppies can develop.
“They should not go into heat after they are spayed because the uterus and ovaries are removed. They absolutely cannot get pregnant without a uterus, but if some of the ovary was inadvertently left or not completely removed they can have heat cycle type behavior and attract males..”~Dr. Debbie, veterinarian
Correcting the Issue Requires Skill
If your dog is in heat after being spayed, you may want to consult with your vet and determine what’s the best course of action. It’s best if you contact the vet who performed the spay procedure in the first place.
An option for a dog going in heat after being spayed may be using medications to stop your dog from going into heat, but these can cause a list of unwanted side effects, which is why they aren’t very popular. Also, this would do little for tackling the problem long term.
The other, more permanent solution is retrieving the ovarian tissue left behind. This can be a tricky task, as it requires an exploratory surgery that should be left to the skill of a specialist. If you decide to go this route, consider that it might be best done when your dog is in heat as the associated tissue swelling can make the tissue easier to find. Consult with your vet for the most appropriate time.
And what if you do nothing at all? You may be tempted to go this route and just accept your dog going occasionally into heat, but consider that there is much more going on with ovarian tissue left behind. As your dog continues to go through several heat cycles and ages, there are chances she may develop mammary cancer or what’s known as a “uterine stump infection,” explains veterinarian Dr. Joey. If your dog appears lethargic, has a fever, lost her appetite and has a bloody/pus-like discharge, see your vet as soon as possible.
“Complications of ovarian remnant syndrome include the formation of granulosa cell tumors, uterine stump pyometra, and mammary neoplasia; thus surgical excision of the ovarian remnants should be highly recommended.”~Cheryl Sangster
The Cost of Fixing
How much should you expect to pay for an exploratory surgery in search of the remaining ovarian tissue left behind? The cost for fixing ovarian remnant syndrome may certainly vary depending on location and what is being done.
If you are able to trace back the vet that spayed your dog in the first place, there are chances you may get a discount.
Generally, the price for an exploratory surgery for remnant ovarian tissue may range anywhere between $300 and $800, with the higher price range involving a specialist such as a board-certified surgeon performing the surgery.
Did you know? According to a review of complications occurring during a spay surgery, ovarian remnant syndrome was found to occur in 12 of 72 cases, basically 17 percent.
- Pearson H. The complications of ovariohysterectomy in the bitch. J Small Anim Pract. 1973;14:257–266.
- The ovarian remnant syndrome in the bitch and queen.Wallace MS Vet Clin North Am Small Anim Pract. 1991 May; 21(3):501-7.
- Granulosa cell tumour in two speyed bitches.Sivacolundhu RK, O’Hara AJ, Read RA Aust Vet J. 2001 Mar; 79(3):173-6.
- Ovarian remnant syndrome in a 5-year-old bitch.Sangster C. Can Vet J. 2005 Jan;46(1):62-4.