Spaying & Neutering May have a Downside

Some Disorders may be More Prone to Occur

To neuter or not to neuter: That is the question. Really? Wasn’t that settled a long time ago? As a veterinarian, obliged to reduce animal suffering, shouldn’t I, of all people, vigorously beat the spay/neuter drum? The oversupply of pets has not gone away.

The behavioral benefits of spaying and neutering are clear. Roaming, urine marking/spraying, and aggression between intact (unneutered) males are greatly diminished. The best reason for continuing early-age sterilization prior to adoption is to reduce the glut of unwanted pets. During the 1980s shelters in the United States euthanized an estimated 17 million cats and dogs each year. Largely because of puppy and kitten spay/neuter programs that figure is now about 3 million. That’s decent progress but for some dogs there may be a downside.

A pair of recent studies, published by the Public Library of Science (PLOS One), found that male golden retrievers neutered before their first birthdays had twice the risk of developing hip dysplasia compared to boys who remained intact. Early neutered dogs had three times the incidence of lymphosarcoma, a common malignant cancer.  Females were 4 times more likely to develop hemangiosarcoma. Mast cell tumors were found in 6% of females spayed after age 1 year while none occurred in the intact girls. Early neutered males and females were more likely to rupture the anterior cruciate ligaments (ACL) in their knees. We don’t yet know if other dog breeds are similar or how removal of the gonads relates to medical problems but these findings are sobering.

There is no simple conclusion. A different study showed that spayed and neutered dogs live longer because they have a lesser risk of trauma and infectious disease. Well, go figure. They stay home watching the Olympics with their grandparents instead of partying with nefarious characters and consorting with those of ill repute.

There is plenty of room for debate. Breast cancer and uterine infections in females and prostate disease and rear end tumors and hernias of males just don’t occur in spayed and neutered dogs. We trade safety in some areas for risk in others. Pet overpopulation is a huge priority but there may be room here for discussion between responsible pet owners and their veterinarians. Individual, informed choices are good things.