Q: Is it really necessary to have my dog spayed? What ‘s wrong with just keeping her away from other dogs when she is in heat if I don’t want to breed her?


By Claudia Bowman

While avoiding unwanted pregnancies and adding to the number of unwanted pets that are killed every year is an important reason to spay your dog, it isn’t the only reason. There are significant health benefits for your dog that simply avoiding breeding will not deliver.

First of all, let’s review a little about your dog’s reproductive cycle. The dog has what is called an estrus cycle or commonly, a heat cycle. The dog’s estrus cycle is different from the monthly cycle of human females. The estrus cycle is made up of blocks of time where the female is receptive to the male and can get pregnant and blocks of time where she is not receptive and cannot get pregnant. These blocks of time where she can get pregnant occur a couple of times yearly on average. It does occur more frequently in some dogs and less in other dogs. This is the period where she is said to be “in heat”.

The female dog goes into heat for the first time at about 6 months old on average, or when she reaches about 80% of her full growth. Giant breeds can take longer and some dogs will go into heat sooner. “Heat” means she is menstruating and a “spay” procedure is an ovariohysterectomy.

If she is spayed before her first heat, it will dramatically decrease her risk of mammary cancer later in life. Mammary cancer is a common cancer in dogs. Studies have shown that the risk decreases by 80% if she is spayed before that first heat.

Female dogs that are not spayed will continue to cycle and go into heat, of course. The lining of the uterus is not shed in dogs if pregnancy is not achieved the way it is in humans. That lining is exposed to repeated cycles of hormones and can become abnormal over time. It is a risk factor for a severe infection of the uterus called pyometra. This infection is often life threatening. Emergency surgery to remove the infected uterus is usually necessary and is very expensive. Depending on where you live it can cost several thousand dollars by the time she leaves the hospital. Having her spayed while she is young and healthy is far less risky and expensive.

Accidents happen. Doors are left open. Male dogs jump fences. This is often how unwanted pregnancies occur in dogs. If she has difficulty giving birth, she could require an emergency C section to save her life. This is also very expensive.

So think about getting your dog spayed for her health and your relationship. You want her to have a long happy life with as few complications and expense as possible.

Dr. Claudia Bowman, DVM, is a member of the Veterinary Emergency & Specialty Center of New England’s Emergency & Critical Care Department. VESCONE doctors provide emergency care, internal medicine, surgery, radiology, ophthalmology, cardiology. Check out VESCONE’s Facebook page and go to www.vescone.com for more information.