Whether performed laparoscopically or traditionally, a spay in the United States generally means removing both the ovaries and the uterus. Not so in Europe, where for quite a long time spays have involved removing the ovaries only. The reason we remove the uterus here is concern over a uterine infection after the operation called stump pyometra.
But there are now rather convincing data that if a dog contracts a uterine infection after a spay, it’s not because the uterus was left intact but because the surgeon left a bit of ovary behind by mistake. Once the ovaries come out, the uterus shrinks and atrophies; it’s not an infection hot spot.
“Twenty years from now,” says Tufts veterinary surgeon John Berg, DVM, DACVS,” my guess is that all over the world a spay will involve only an ovariectomy — removal of the ovaries. We’re beginning to go in that direction even in this country. That’s already how we routinely do it when we do it laparoscopically “