What health benefits are associated with spaying and neutering?

• A. Spaying reduces breast cancer if before first heat; neutering eliminates testicular cancer
• B. Spaying prevents vision problems; neutering prevents ear infections
• C. Spaying eliminates all cancers; neutering eliminates all infections
• D. Spaying causes increased aggression; neutering causes obesity

Answer: (A)

Removing the reproductive organs changes the hormonal environment that can drive certain cancers. When a female dog is spayed, the ovaries are removed, which stops the estrogen-driven risk factors for mammary (breast) tumors—especially when done before the first heat cycle. That early timing makes a noticeable difference in reducing the likelihood of developing mammary cancer later.

For a male dog, neutering removes the testes, which are the source of hormones that can contribute to testicular cancer. Without the testes, the tissue that could become cancerous is no longer present, effectively eliminating the risk of testicular cancer.

The other options propose effects that aren’t supported by veterinary evidence: spaying doesn’t prevent vision problems, neutering doesn’t prevent ear infections, no procedure eliminates all cancers or all infections, and aggression or obesity aren’t universally caused by spaying or neutering. The benefits described in this choice align with how removing hormonal sources and reproductive organs influences cancer risks in dogs.