How Old Can a Female Puppy Be to Get Pregnant?

If your puppy's grouchy, her first heat could be the cause.
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Puppies develop at lightning fast speeds. One week you're bringing your little cutie to your house for the first time, and seemingly the next, she's on the verge of her first heat cycle -- gulp. Female puppies can become pregnant long before they reach a year old, so take the matter seriously.

Fast Blooming Puppies

As soon as a puppy is sexually mature, she's capable of getting pregnant and producing a litter of her own youngsters. Female puppies can, in some cases, get pregnant at ages as young as 5 months. This age, however, is on the early side.

Late Blooming Puppies

Although some wee pups can indeed reproduce at a mere 5 months in age, breed and size have a lot to do with it. For the most part, puppies of smaller sizes attain reproductive capabilities faster than those of bigger breeds. While one Yorkshire terrier puppy might get pregnant at just 5 months in age, a massive Great Dane might not achieve sexual maturity until she's between 18 months and 2 years old -- a major difference. Just as female humans mature at different paces, the same applies to canines.

Average Age Range for Maturity

Some dogs indeed can mature at both earlier and later points than 5 months, but the majority of them go into their initial heat cycles -- and therefore gain the ability to get pregnant and bear young -- when they're in the range of 6 months and 1 year old.


If your puppy goes into heat, then you know that she is indeed old enough to get pregnant, whether she's 5 months or more than a year in age. The heat cycle usually happens twice annually in dogs. When your puppy is in heat, she'll probably give a lot of indications of it to clue you in. Some signs of a female dog in heat are anxiety, agitation, uncharacteristic fierce behavioral patterns, vulva swelling, urinating more than normal, lack of concentration and discharge coming out from the vagina.


Female puppies frequently get spayed before their bodies are mature and developed enough to become pregnant. If a puppy is spayed before becoming sexually mature, not only does the surgery prevent pregnancy, it also stops the heat cycle from ever beginning, along with all of the symptoms and behaviors commonly associated with it. For these purposes, the ASPCA recommends fixing dogs prior to the age of maturity -- think before roughly 6 months. Inquire beforehand with your veterinarian on a sensible and safe time frame for spaying your precious pup.