Dogs stop going into heat after a certain age?

That's generally true, but it's not a hard and fast rule. Here's a breakdown:

* Most dogs stop going into heat between 6 and 10 years old. This is when their reproductive cycles naturally slow down and eventually stop.

* The age of their last heat cycle can vary depending on breed and individual factors. Some smaller breeds might stop earlier, while larger breeds might continue to cycle later.

* Some dogs may experience irregular cycles in their later years. Their heats might be less frequent or the bleeding might be lighter.

* It's possible for a dog to go into heat after 10 years old. This can happen if the dog has a hormonal imbalance or other underlying health issues.

It's important to consult your veterinarian about your individual dog's reproductive health and when to expect their last heat cycle. They can help you understand what's normal for your dog and if any changes in their cycle are concerning.