When Will My Puppy Go Into Heat?

One of the more critical choices you’ll make when you adopt a puppy is whether to adopt a male or female. As with all mammals, certain physical differences come with either gender and certain traits as well. Depending on your lifestyle, one gender might be more fitted to live with you than the other.

One of the biggest differences between male and female puppies is that, as adults, females can have puppies of their own. If you’re planning to breed your puppy someday, adopting a female is your best (and only) choice. Also, females are known for having fewer problems with aggressive behavior and are innately more protective of their humans.

If you decide to adopt a female pup, whether you plan to breed her or have her spayed, one thing you’ll deal with at least once is their first menstrual cycle. With dogs, this is known as “going into heat” and, as with humans, it can be a confusing and messy time for your puppy and you.

I was thinking recently about the first time I had a puppy that went into heat and how shocked I was by all the blood. If you’re like me, seeing someone else’s blood usually means they’ve had a traumatic incident which, luckily, wasn’t the case. (It was, however, a real pain to clean up!) This got me thinking about a question one of my readers asked just the other day about this very subject, “when will my puppy go into heat?”

The answer to this delicate doggy question is that, on average, most puppies go into heat the first time at around 6 months of age. However, this can vary significantly. Some puppies can go into heat as early as four months old. On the other end of the spectrum, some very large dog breeds might not go into heat until they reach two years of age.

Now that you know when your puppy will go into heat, more or less, I’m sure you have other questions about this particular subject. What are the signs that your puppy is about to go into heat, for example, and how long will your puppy’s first heat last? I’ve got the answer to those questions and several more below to prepare you for when this inevitable (and natural) event happens.

What are the Signs that your Puppy is About to Go into Heat?

If you know what to look for, several signs will alert you to the fact that your puppy is about to have her first heat. Some will be rather obvious if you spend a lot of time with your puppy. If you’re not home with your puppy often, they might not be as obvious, however. The signs your pup is about to have her first heat include:

  • A swollen vulva. (That’s a layperson’s terms for a dog’s vagina.)
  • Acting nervous, slightly aggressive, and appear more agitated than usual.
  • Being very receptive to male dogs. (A sure sign.)
  • Licking their genitals much more than usual.
  • If they are peeing more than usual.
  • When their tail’s position has changed from where it normally hangs.

Often, a puppy will exhibit several of these behaviors simultaneously. That being said, some will only exhibit one or two, and, occasionally, you won’t have any clue that your pup is about to make a gigantic, bloody mess all over the kitchen floor. (It happened to me recently, so the image is still fresh.)

How Long Will my Puppy’s First Heat Last?

From my research, it seems that a puppy’s first heat lasts more or less the same amount of time as any other heat, about 2 to 4 weeks. Typically, you will notice that your puppy’s vulva has returned to its normal size, indicating that her cycle has ended. Another clear sign is that your puppy is no longer bleeding. 

During your puppy’s first heat, she might not be as receptive to male dogs as she will be during future heats. (Some might be, however, so you’ll need to wait and see.)

Interestingly, even though most female dogs go into heat every six months, it might take your puppy up to 18 months for her heat cycle to become regular. Once that occurs, she will go through this heat cycle every 6 months, give or take a few days, until the end of her life. 

Can my Puppy Be in Heat without Bleeding?

Yes, a puppy can go through heat without bleeding. In fact, she can go through an entire heat cycle without her vulva enlarging, without excessive licking, and even without being more receptive to male dogs. (Your puppy’s behavior might not change in the slightest.) This unusual heat cycle is called a silent heat and, while relatively rare, it does happen.

If she has a silent heat frequently, with little signs of proestrus and not attracting males, a veterinary exam is your next step. This situation is unusual, however. 

Also, veterinarians recommend housing a female with silent heat with a female known to have no problems and coming into heat (proestrus). The second dog can often trigger the first to go into a full-blown heat.

What Do I Do with My Dog while She’s in Heat?

What to do with your puppy while she is in heat will be different for every puppy parent. You don’t need to treat them differently regarding their food, toys, crate time, etc., but be aware that they may be stressed, anxious, or vulnerable.

One thing you might find is that your dog wants to cuddle with you a lot more than usual. This is a natural behavior for a female dog in heat and is a great time to bond with your puppy. Also, having a few items handy will make this time easier on both of you, including:

  • You must give your puppy plenty of water when she’s going through heat and high-quality kibble.
  • Give your puppy a special blanket for when she is in heat. Then place it wherever she likes to cuddle up or asleep. The upside is that, after her heat ends, you will only have one blanket that needs to be cleaned.
  • While it may look a little silly, many folks use doggie diapers for their female dogs when they go into heat. Several brands are available, although they can slide off easily in some cases, depending on your dog and their particular doggy body. For some, a bodysuit with the diaper underneath would work better.
  • Keep disposable baby wipes available so that you can clean them up quickly if an accident occurs (and they will).
  • Scolding your puppy if she makes a mess when going through heat is never recommended. 
  • Be sure to increase the number of potty breaks you give your puppy during the day and night. It’s very common for a female dog to urinate more frequently when in heat.

Final Thoughts

When will my puppy go into heat is a question I hear occasionally. With more and more people spaying and neutering their pets, however, it’s more of a concern for breeders than anyone else. Typically, a puppy will go into its first heat at around six months, although, for larger breeds, it might take as long as 18 months. Once they have a regular cycle, most dogs will go into heat every 6 months.

Did you find today’s blog interesting and informative? I hope so, as I try my best to pack these full of useful and actionable information. Please see my other blogs if you need more info or have questions about other puppy-related issues. All of them are loaded with information, advice, and insightful stuff to help you become a better puppy parent.