Did you know that unspayed female dogs have higher risks for mammary tumors? Since there is a 50-50 chance that a mammary tumor in a dog is malignant, veterinarians are always keen on informing dog owners about the importance of spaying female dogs.
An important predisposing factor of mammary tumors is the spikes of estrogen (female hormone) that occur during a female dog’s heat cycle. To eliminate the risk for mammary tumors, a dog has to be spayed at 6 months old or before her first heat cycle. The risk increases with each heat cycle that the dog goes through.
Female dogs that are spayed when they are older than 2 years old have no more protection against the problem. Also, carrying excess weight or receiving hormone replacement therapy can further increase a dog’s risk for mammary tumors.
In addition to lowering the risk for mammary tumors, spaying can also eliminate the risk of pyometra, a serious infection of the uterus. Your Newmarket, ON veterinarian can readily answer your concerns about the pros and cons of spaying.