What to do when your bitch comes into season (heat)

If you own a bitch (female dog) that is unspayed, then once she reaches maturity, she will come into heat regularly, once or twice a year. This is referred to as being ‘in season’ and is the period of time when she’s receptive to mating. Therefore care must be taken if you do not want a litter of unwanted puppies!

It is not always obvious that the dog is in season, especially when it is the first season. If you intend on breeding your dog, then you will of course need to learn what it means when she comes into season, how to manage this, and how to take care of her. Caring for a bitch in heat is much more complicated than caring for a spayed bitch, and if you don’t intend to breed your dog at some point, having her spayed is an important part of being a responsible pet owner.

When does heat start?

Dogs can go into heat as young as 4 months in small breeds – but it usually starts when they are about 6 months old. However some bigger breeds might not go into their first heat until they’re 18-24 months old. It is strongly advised not to breed your dog during their first cycle as their eggs are not yet mature enough and they wouldn’t have reached full maturity – if you are planning on breeding your dog, then your vet will be able to tell you when the dog is mature enough to breed. However your bitch will be perfectly capable of conceiving a pregnancy during her first season, so you must take care of her and keep her away from male dogs during this time.

How often do dogs go into heat?

This varies from dog to dog but generally, bitches come into season once or twice a year – however there are significant levels of variation between different breeds of dog.

How long does heat last?

Bitches generally remain in heat for about 3 weeks at a time, although, again this can vary depending on the breed – anything between 2 and 4 weeks is normal. If your dog remains in heat for longer than 4 weeks, consult your vet as there may be an underlying problem.


What are the signs of a dog in heat?

Your dog may appear nervous and more alert than normal. She might also urinate more than she usually does. You’ll also probably notice a change in her behaviour. This is caused by a shift in her hormone balance. Your bitch’s back end will also often be visibly larger and darker looking than usual, with the vulva swollen and the tail often raised.

At what age can dogs be spayed?

Generally, a vet can spay a dog when she is as young as 2 months old. However, it is best to consult with your vet for specific recommendations regarding the best time to spay your dog.

Can dogs be spayed when they are in heat?

If you have decided to have your dog spayed and you on’t intend to breed her, it’s important that you don’t arrange it when you know your bitch is in season or close to coming in season. Spaying while in season is more risky than at any other time, as the uterus, vulva and womb will all be inflamed. Unless there is an urgent reason for spaying at this time, a vet should refuse to spay your bitch until after the heat cycle has finished.