An ovariohysterectomy is a surgical procedure that removes both ovaries and the uterus from a female animal. It is the most common form of spaying in dogs and cats, and it permanently prevents pregnancy, heat cycles, and several serious reproductive diseases. If your veterinarian recommended this surgery, you’re likely looking at a routine procedure with a well-established safety record.
What the Surgery Removes
The name breaks down neatly: “ovario” refers to the ovaries, “hyster” to the uterus, and “ectomy” means removal. During the procedure, a surgeon removes both ovaries, the uterine horns (the two branching arms of the uterus), and the body of the uterus. The connective tissue that holds these organs in place, called the broad ligament, is also detached. Blood vessels supplying the ovaries and uterus are tied off and sealed before the organs are removed.
Because the ovaries are the primary source of reproductive hormones like estrogen and progesterone, removing them eliminates heat cycles entirely. Removing the uterus as well means there is no remaining tissue where infections or tumors could develop later.
Why Veterinarians Recommend It
Most ovariohysterectomies are elective, meaning they’re done for sterilization rather than to treat an existing problem. Many owners choose the procedure to avoid the behavioral signs of heat, including vulvar discharge, restlessness, and attracting male animals. But the surgery also serves as prevention against several conditions that are common and sometimes life-threatening in intact females.
Pyometra, a bacterial infection of the uterus, affects up to 25% of unspayed female dogs over their lifetime. It can progress rapidly and become fatal without emergency surgery. Spaying eliminates this risk entirely by removing the uterus before infection can take hold.
The surgery also dramatically reduces the risk of mammary tumors, which are the most common tumors in intact female dogs. A landmark study found that dogs spayed before their first heat cycle had just 0.5% of the mammary tumor risk compared to unspayed dogs. Spaying after one heat cycle still offered significant protection, with dogs retaining only 8% of the risk. By the time a dog has gone through three or more heat cycles, the protective benefit drops considerably: one screening study in Brazil found mammary tumors in 27.6% of dogs spayed after their third cycle, compared to 9.4% spayed earlier.
When the surgery is medically necessary rather than elective, the most common reasons include pyometra, uterine tumors, serious uterine trauma (often from difficult labor), chronic uterine infections that don’t respond to medication, and termination of an unwanted pregnancy when permanent sterilization is also desired.
How the Surgery Works
The traditional approach uses a single incision along the midline of the abdomen, below the belly button. Through this opening, the surgeon locates one uterine horn and follows it to the ovary. A ligament anchoring the ovary is carefully broken to bring the ovary into view outside the body. The blood vessels feeding the ovary are clamped in multiple places and tied off securely before cutting, a step that’s critical for preventing bleeding. The process is repeated on the other side.
Once both ovaries are freed, the surgeon works down to where the uterus meets the cervix. The blood vessels here are clamped and tied off, the uterine body is cut, and the entire reproductive tract is removed as one piece. The abdominal wall is then closed in layers, with the skin sealed using sutures, staples, or surgical glue depending on the veterinarian’s preference.
The whole procedure typically takes 30 to 60 minutes for a routine spay in a healthy animal, though it can take longer in larger dogs, overweight animals, or those with active uterine disease.
Ovariohysterectomy vs. Ovariectomy
Some veterinarians, particularly in Europe, perform an ovariectomy instead, which removes only the ovaries and leaves the uterus in place. This is a less invasive procedure with a smaller incision and shorter surgical time. A natural question is whether leaving the uterus behind creates problems down the road.
A long-term comparison study found no significant differences in complication rates between the two approaches. Dogs that had only their ovaries removed did not develop uterine infections or other uterine diseases afterward, because without ovarian hormones, the uterine lining stays inactive and doesn’t create the conditions bacteria need to thrive. Urinary incontinence, a known long-term side effect of spaying, occurred at similar rates in both groups. The researchers concluded there is no medical reason to remove the uterus during routine spaying of a healthy animal. However, if any uterine disease is already present, full removal remains necessary.
Risks and Complications
Ovariohysterectomy is one of the most commonly performed surgeries in veterinary medicine, and serious complications are uncommon. Overall complication rates in published studies range from about 4% to 35%, with most falling at the lower end when performed by experienced surgeons on healthy animals.
The most frequently reported intraoperative complication is bleeding, which occurs when a ligature slips or a blood vessel isn’t fully sealed. In most cases this is identified and corrected during surgery. Less common complications include accidental injury to the ureters (the tubes connecting the kidneys to the bladder), or minor trauma to nearby organs like the intestines or spleen.
In the two weeks after surgery, the most common issues are wound discharge and reduced appetite. One large study found wound discharge in about 1% to 9% of dogs, and temporary loss of appetite in 3% to 17%, depending on the age at which the dog was spayed. Dogs spayed before their first heat cycle tended to have fewer postoperative complications overall, likely because their reproductive organs are smaller and easier to access surgically.
What Recovery Looks Like
Your dog or cat should stay indoors the night after surgery, going outside only for brief leash walks to relieve themselves. Over the first 24 to 48 hours, behavior gradually returns to normal, though grogginess from anesthesia is expected on the first day. A mild cough after surgery is common and results from the breathing tube used during anesthesia. It typically fades within a few days.
Activity needs to be restricted for 7 to 10 days. That means no running, jumping, climbing stairs, or rough play, anything that could strain the incision site. Most animals feel better within a day or two and will want to be active well before their incision is ready for it, so this is the hardest part for most owners to manage.
Animals will instinctively try to lick the incision. An Elizabethan collar (the cone) or a recovery suit prevents this and should be used any time you can’t directly supervise. Licking introduces bacteria and can pull sutures loose, both of which lead to infection or reopening of the wound. Watch the incision daily for increasing redness, swelling, discharge, or a foul smell, all of which warrant a call to your veterinarian.
Laparoscopic Spaying
A growing number of veterinary clinics offer laparoscopic ovariohysterectomy, which uses small camera-guided instruments inserted through two or three tiny incisions rather than one larger opening. The result is less tissue trauma, which translates directly to less pain afterward.
In cats, a study comparing laparoscopic-assisted spay to traditional open surgery found significantly lower pain scores at one, two, and four hours after surgery. Stress markers were also lower in the laparoscopic group. In dogs, the technique is associated with better visualization during surgery, reduced pain and stress, lower complication rates, and faster return to normal activity. Both approaches are considered safe and effective, but the laparoscopic version offers a gentler recovery. The tradeoff is typically higher cost, since the equipment is expensive and the technique requires specialized training.