Sponsor the spaying and neutering of a shelter animal. The official goal of the British Columbia SPCA is to reach zero euthanasia of adoptable animals - and we are making real progress. The technical term is ovario-hysterectomy. As the surgery is done under a general anaesthetic it is painless. The operation for both males and for females is straightforward and low risk.
Recovery is usually uneventful.
The worst your pet might experience is some discomfort for a short time after the operation. The usual recommendation is at 6 to 7 months for both cats and dogs. Your veterinarian should be consulted to determine the best time for your pet. Allowing a female dog or cat to produce a litter does not have any benefits. There are health risks to the mother during the pregnancy and when giving birth.