How Long do Dogs Stay in Heat?

The average female dog goes into heat (properly called estrus) once every 6 to 7 months after she has reached the age of about four or five months, although this can vary slightly from breed to breed. The usual cycle lasts for about 21 days.

The estrus cycle has three separate and distinct phases that a dog’s owner should become familiar with. The first, often called “preestrus” is when a dog’s owner may notice bleeding from the vulva, which can range from very slight to a noticeable flow that leaves evidence of the dog’s present condition wherever she sits. These days most pet supply stores do carry “dog panties” that hold special canine sanitary napkins to eliminate the mess. The entire vulva will also usually swell and the dog will also often need to urinate more frequently than usual.

The second stage, the actual estrus, occurs 8 to 10 days into the cycle and it is at this time that a female canine will be willing to mate, usually with any male she happens to encounter. If you are not looking to add any canine members to the family at this time the best idea is to keep her inside, being careful even on short walks because many a keen female has been known to break off their leash to follow an interesting “boy next door”.

In the last stage of heat the female dog will still be giving off “signals” to male dogs but will usually be no longer interested in their attentions, often biting and snarling should they try to come near her. After this is over she should return to her cheery ‘normal’ self for at least another half year.