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My Dog’s In Heat – Understanding Estrus Cycles in Dogs

Written by FOTP Team


Springer Spaniel on sofa

My Dog’s In Heat – Understanding Estrus Cycles in Dogs

ESTRUS refers to the time your dog ovulates and becomes fertile – drawing dogs from all over the neighborhood with her hormones! As owners we might be a bit distressed to see our dogs going through it, but it’s going to be okay. Here’s what to expect, and how to care for your dog during her estrus cycle. 

What Happens When My Dog’s In Heat?

Female dogs will come into their first season at around 6 months old, and it will last for 2-4 weeks. They’re effectively completing maturity and can become pregnant during this time. (Note that vets don’t recommend breeding from the first season.) It’s an event which most dog owners have to handle, but it doesn’t have to be a big deal. 

Watch out for the signs of her first season when your dog is almost 6 months (and up to 24 months). 

Her vulva will become swollen, but the first thing you’ll probably notice is a bloody discharge, which varies between dogs, with smaller dogs often experiencing less discharge than larger dogs. 

You might liken it to human menstruation and you wouldn’t be totally wrong. Your dog’s behavior is likely to change as her hormones surge!

Look out for:

  • Increased urination, sometimes in the home
  • Licking her genitals
  • Nesting behavior
  • Increased friendliness with other dogs
  • Whining or crying
  • Stressed behavior (hormonal changes can be confusing). 

The estrus cycle has three distinct phases. 

  1. The first phase is Proestrus, the very first part when her body begins to change – there will be a bloody discharge at this point. 
  2. Next is Estrus, where your dog is fertile. The discharge becomes more watery and she will be looking out for suitable mates. 
  3. Diestrus is the third phase when her body is gradually returning to normal; the discharge might become bloody again but your dog will stop showing interest in other dogs. 

Veterinarians advise keeping your female dog well away from male dogs during the ENTIRE estrus cycle. Since male sperm can live for around a week, and we can’t always be sure what stage the female dog is at, all sexual activity is inadvisable – unless you want your female dog to become pregnant. 

Does a dog in heat smell? She doesn’t really smell to the human nose – but she will have a powerful scent to other dogs! This is why you’ll need to keep your female dog kept away from male dogs, even in her own yard (where it’s best to supervise). Other female dogs may react negatively to her during this time, and can be aggressive – as they perceive her as a threat. See below for our tips on caring for her.

Will there be blood everywhere? It varies from dog to dog and, although the blood can be messy, it’s often not as much as you’d think. Your dog will probably clean herself quite a lot; smaller dogs bleed less, too. If you’re worried about the bleeding, you can use a nappy or restrict your dog’s movements to one room. 

Is my female dog in pain when she’s in heat? It is thought that some female dogs can experience pain during estrus, but it’s not very common; the increased hormones can certainly lead to feelings of confusion, as well as seeking out male dogs to initiate breeding! Your dog might experience some or none of these symptoms. 

How often will my dog be in heat? Estrus cycles normally last around 6 months so your dog will be in heat approximately twice a year. It takes a while for the cycle to settle into a rhythm, so her first few might be a bit unpredictable. 

Caring For A Dog In Heat

When your female dog experiences her first estrus cycle, it can be a bit of a surprise. She doesn’t have our communication skills, she hasn’t been warned about the bodily changes by her mom, and the new feelings can be startling. So if she’s prone to anxiety, she might exhibit some symptoms of it when her cycle begins.

One of the best things you can do is help her to relax: be a reassuring presence, and maybe even bring home some new toys to distract her. Spending time with her will be important as she’ll gain comfort (and oxytocin) from your presence. 

  • Can I walk a dog when she’s in heat? This is the first thought that occurs to most of us! Your young dog probably enjoys her daily walks and needs them to stay healthy, too. But if you walk her during the estrus cycle, there’s a high risk of unwanted pregnancy. Male dogs will sniff her scent from surprisingly far away. Even if you’re 100% positive you can keep your dog safe, you’re still spreading her scent around the neighborhood which is going to wind up other dogs. It’s not considered good etiquette to cause problems for other dogs and owners. 
  • What preparations should I do at home? When she’s in heat, your dog will need a secure space that’s apart from any other dogs in the home. You’ll even need to keep her apart from brothers, sisters, mom and dad – because dogs will mate indiscriminately. Also be careful that the yard is fenced and there are no gaps for male dogs to squeeze through!

Should My Dog Be Neutered Before Or After Her Season?
The benefits of spaying your female dog are varied. If you don’t plan to breed pups, an unneutered dog can cause a lot of hassle. It won’t be easy to walk her during her season and she will continue to produce hormones which can lead to:

  • Mammary tumors\
  • Cystic endometrial hyperplasia (an issue with the lining of the uterus)
  • Pyometra (an infection inside the uterus)

Veterinarians often recommend that spaying is carried out after this first season (although research is inconclusive) – sometimes a young dog’s vulva will only be fully developed after her first season. There is also an increased risk of urinary incontinence for dogs who are spayed before a season. Before making your decision, read around. Some research has suggested that waiting for a season is beneficial for breeds including Labradors, German Shepherds,according%20to%20a%20university%20release. and Golden Retrievers – reducing the incidence of orthopedic problems and cancers. 

Do you have any more questions about your female dog’s first season? Let us know in the comments.