I recently put out a female incontinence survey and many of you were kind enough to respond and share it around- we got 210 GSMD responses and 49 other large breed dogs, which is awesome. Multiple people have asked me about ovary sparing spay (OSS) to prevent incontinence so here you go! I have put together information for your vet about OSS as well as the results of the incontinence survey.
Total risk of incontinence in GSMD was a whopping 56% and in other large dogs 36% amongst responders. GSMD were more likely to be spayed at a later age (only 10% <12 months old, 27% 12-24 months, 37% >24 months old and 26% never spayed or OSS.) Non-GSMD were 56% spayed under 24 months old.
Incontinence was broken up into 4 groups- dogs that developed it (or not) before 6yo and over. I find the most helpful groups the GSMD who were over 6 and not incontinent (46 dogs in this group) and dogs under 6 who were incontinent (83 dogs.) I think we would all like our dogs to be members of the first group and not the second.
GSMD who are/were over 6 and never incontinent were 20% spayed under 24 months and 35% never spayed or OSS.
GSMD whose incontinence started under 6 were 60% spayed under 24 months old, and only 5% never spayed or OSS.
GSMD whose incontinence started over 6yo (36 dogs) were 25% spayed under 24 months and only 5.5% never spayed or OSS. Most of these dogs were breeding bitches spayed after a career, so it is not known how soon after spaying the incontinence develops, although many people report that it is within months.
GSMD who are under 6 and not incontinent (45 dogs) were 22% spayed under 24 mo old and 69% never spayed. Obviously these dogs are still young so could develop incontinence later.
As far as exact ages, 77% of the 21 dogs spayed under 12 months were incontinent and 75% of the 57 dogs spayed 12-24 months of age were. 75% of the 44 dogs spayed >24 months who did not have puppies were incontinent but only 59% of the 34 who had puppies were incontinent. Only 13% of unspayed bitches were incontinent.
The other large breed dogs had similar spreads in the age ranges for incontinence although there were many more dogs spayed young that developed late incontinence or not at all- the risk was lower across the board.
27 dogs had multiple urinary tract infections as puppies but this did not seem to increase their risk of incontinence too much- overall risk was 66% amongst this group, with a similar spread as the unaffected dogs. Unfortunately, 91% of the 11 dogs spayed due to pyometra developed incontinence. Urinary tract infections in puppies are often linked to vaginitis which can cause inflammation of the urethra so later incontinence is likely related. Pyometra is caused by endometrial inflammation under hormonal influence so it is likely that the incontinence is due in part to the inflammation. The general incontinence risk was about the same for all groups with the UTI/pyo dogs subtracted so these are not primary risk factors for the development of incontinence.
So what the data seems to tell us is that there is protection against incontinence by leaving hormones intact but it is not perfect by any means. Leaving bitches intact means that owners have to deal with behavioral changes, mess, inability to go to certain dog events, and risk of pregnancy. Intact bitches are susceptible to pyometra, ovarian cancers and mammary cancers.
Only 5 dogs in the survey had the ovary sparing spay. Two still had incontinence. Due to this small group, we do not know is if it provides protection as well as leaving dogs fully intact, although it is suspected so. Ovary sparing spay should never be done for treatment of pyometra. Bitches affected with the endometrial inflammation and bacterial infection need to have that treated by ovariohysterectomy or complex medical management.
The long and short of it is that the risk of incontinence in spayed females is very high (approx. 75%) no matter what age they are spayed. The risk is much lower in unspayed dogs (13%.)
Incontinence is often very easy to manage with medications, so it can be easy to overlook as a health concern especially by veterinarians, but it is something to be mindful of as we make decisions on when and whether to spay our girls.
Ovary Sparing Spay: What, Why, How
Traditionally bitches in the United States have been spayed for multiple reasons, but most notably for population control, avoidance of annoying heat cycles and prevention of mammary cancer. Ovariohysterectomy is the most common procedure, which involves removal of the ovaries and uterus. Recently some studies have shown that there is benefit to leaving hormones intact longer for bone growth and possibly for some cancers so people are starting to reconsider spaying. Pyometra is a life-threatening infection in the uterus that can occur in bitches with intact hormones and prevention is one of the main reasons why we spay older bitches. Ovary sparing spay or hysterectomy is a procedure very similar to a regular spay except one or both ovaries are left in place.
Ovary sparing spay sounded ridiculous to me at first: you still have the risks of stump pyometra, mammary cancer and you still have to deal with heat cycles (which always seem to interfere with a trial). Prevention of incontinence is the main reason why Swissy owners consider ovary sparing spay, and incontinence in a giant dog is a giant deal.
Feel free to photocopy this and take to your vet, most skilled surgeons with traditional ovariohysterectomies in giant dogs can perform an ovary sparing spay also, but they will need you as the owner to sign off on this list of risks with this surgery.
Advantages to Ovary sparing spay vs regular spay:
Decreased risk of incontinence
decreased risk of pyometra (stump pyometra still possible)
potential decreased risk of some cancers
potential decreased risk of some joint issues
Disadvantages to ovary sparing spay vs traditional ovariohysterectomy:
Bitch will still come into heat and cycle, less bleeding but still cannot compete in trials and will need management
If bitch is bred during this time (especially by a larger male) she could potentially develop sperm peritonitis, which is deadly. This is a severe complication and owners need to be vigilant that the bitch does not get bred.
Stump pyometra is a definite concern- this is minimized by proper technique for the ovary sparing spay
Torsion or cancer in the remaining ovary is possible
Mammary cancer risks are higher – there is already a higher risk with waiting until after a bitch has cycled before spaying
Most veterinarians recommend yearly ultrasound of the remaining ovary and mammary glands to catch early issues as much as possible
Larger incision is needed and surgery cannot be done laparoscopically
Technique for Ovary Sparing Spay (for your vet)
Similar to traditional ovariohysterectomy but need a larger incision, leave one ovary and remove all of cervix as well
Try to not break down the suspensory ligament for the ovary you are leaving too much to decrease risk of torsion, and ligate between the ovary and uterus.
Remove entire cervix and every bit of uterine tissue
Note which ovary you left and make sure records stay with the dog
Consider yearly ultrasounds of the remaining ovary and mammary glands to catch early issues