This is a short informational handout that I developed for my clients discussing simply and briefly the two most common approaches to spaying female dogs. For those interested in more detail, the relevant references are provided.
What is a Spay?
“Spaying” refers to any surgical procedure which removes the ovaries, the source of hormones that cause female dogs to have estrus cycles (“heats”) and allows them to reproduce. There are actually several different ways to spay a female dog. Removing only the ovaries is called an ovariectomy. This can be done through a surgical incision into the abdomen, which is most common, or through several small holes using a special instrument called a laparoscope. Removing both the ovaries and the uterus is called an ovariohysterectomy, and this procedure also can be performed through open surgery or laparoscopy.
Historically, veterinarians in the United States and Canada have mostly performed ovariohysterectomies, while vets in Europe and other places have more often done ovariectomies. However, ovariectomies are becoming more common in the U.S. and are now being taught as the procedure of choice in some veterinary schools.
Why Spay a Dog?
There are several benefits to spaying female dogs. Spaying prevents them from reproducing, which helps reduce the large number of unwanted puppies that must be adopted or euthanized every year. Spaying also prevents infections of the uterus (pyometra). Research has also suggested that spayed female dogs are less likely to get mammary tumors (breast cancer) than intact females, though not all studies agree. And there is some evidence that spayed females may live longer than intact females.
As with all medical procedures, there are also some risks to spaying. Complications associated with surgery are generally uncommon and mild, but serious complications can occur. Spayed females may also be at increased risk of urinary incontinence (leaking urine) later in life, and some orthopedic problems and types of cancer may be more common in spayed dogs of some breeds, though the information on these risks is quite incomplete.
Which Type of Spay is Better?
There is very little difference in the outcomes of different types of spay surgeries. The benefits are the same whether the ovaries and uterus are removed or only the ovaries. Because ovariectomy involves a smaller surgical incision and is generally quicker to perform than overiohysterectomy, there may be a slightly lower risk of surgical complications and a little less discomfort for the patient with this procedure. Laparoscopic procedures require even smaller incisions, so they might be less uncomfortable than open surgeries, but they take quite a bit longer and require expensive specialized equipment.
Some vets believe it is safer to remove the uterus as well as the ovaries in older females who have gone through several heat cycles or have had one or more litters, though there is little research on this subject.
Since there are no universally accepted guidelines for when to perform different types of spay surgery, individual veterinarians may make different decisions about the best procedure for any individual pet. A pet’s medical record will reflect which procedure was performed so there is no confusion in the future about whether or not the uterus has been removed.
- van GoethemB. Schaefers-Okkens A. Kirpensteijn A. Making a rational choice between ovariectomy and ovariohysterectomy in the dog: a discussion of the benefits of either technique Vet Surg. 2006;35(2):136-43.
- Lee, S. S. Lee SeungYong. Park SeJin. Kim YoungKi. Seok SeongHoon. Hwang JaeMin. Lee HeeChun. Yeon SeongChan. Comparison of ovariectomy and ovariohysterectomy in terms of postoperative pain behavior and surgical stress in dogs. Journal of Veterinary Clinics. 2013;30(3):166-171.
- McKenzie, BA. Evaluating the benefits and risks of neutering dogs and cats. CAB Reviews: Persp in Agricul, Vet Sci, Nutr, Nat Res. 2010;5(45).
- Okkens AC, Kooistra HS, Nickel RF. Comparison of long-term effects of ovariectomy versus ovariohysterectomy in bitches. J Reprod Fertil Suppl. 1997;51:227-31.
- DeTora M, McCarthy RJ. Ovariohysterectomy versus ovariectomy for elective sterilization of female dogs and cats: is removal of the uterus necessary?J Am Vet Med Assoc. 2011;239(11):1409-12.