I Think My Pet is in “Heat” – What do I do Now?

Written by Dr. Chantal Rittwage

Lost track of time?  Did her first heat come earlier than expected? Rescued a cat and were unsure of how old she was when you took her in?  Considering breeding?  Have a large or giant breed dog and your vet recommended waiting until after her first heat to have her spayed?

Whether it was intentional or accidental, you pet may now be in “heat” (starting her estrous cycle when she is fertile).  The following are tips and tricks on how to recognize heat in cats and dogs, and what to do if she is cycling:

Signs of Heat in Cats

  • Usually first occurs at about 6 months of age, but can vary slightly depending on the time of year (breeding ‘season’ for cats is between January and late fall).
  • Become demandingly affectionate: relentlessly rubbing on people, furniture and floors.
  • When petted along the back, will raise their rear and shift the tail to the side.
  • Become very vocal
  • May pee more frequently, or even start to ‘mark’
  • May even start to see more male stray cats hanging around your property and marking the perimeter.  Some may even try to enter the house to mate with your cat.

**It is uncommon for cats to have vaginal bleeding (or a “period”) during their cycles**

So, What Do You Do About It . . .

This ‘heat’ cycle will only last between 1-7 days, but she will only remain ‘out of heat’ for 1-2 weeks before starting all over again.  If she is an indoor cat, during this period, she will be at a high risk of trying to escape to be with her lovers.  If she’s an outdoor cat, there is a very good chance she will become pregnant as cats are “induced ovulators”; meaning cats don’t have to time their breeding’s, they can effectively breed at any time during the heat cycle.  If you don’t want to breed your cat, it is extremely important to keep her indoors at all times and make her spay appointment with your vet for ~1 week after her heat cycle has finished.  If you cat has started to “mark” on furniture or walls, there are pheromone sprays (Feliway) that can be used to reduce this behavior.  If you think your cat may have been bred and want to continue the pregnancy, contact your vet and they can give you lots of information on what to expect and how to prepare.


Signs of Heat in Dogs

  • Usually first occurs at about 6 months of age, though can vary drastically by breeds.  Small breed dogs can go early, though large and giant breeds may be as late as 18-24 months.
  • The earliest sign of ‘heat’ is swelling of the external vulva, though this can go unnoticed in furry dogs.
  • From the beginning of the heat period, she will be attractive to male dogs, but not usually receptive until about 7-10 days into the cycle.  ***Some will become aggressive towards other dogs during this time***.
  • There will be bloody discharge from the vagina for about 2-3 weeks, progressing from thick, dark blood to a watery, pinkish-red at about 7-10 days.
  • She may start to pee more often on develop a ‘marking’ behavior.
  • You may notice male dogs marking your property to mark their ‘territory’.

So, What Do You Do About It . . .

A dog’s heat cycle will last between 2 and 3 weeks and ends when there is no more discharge and the vulva has returned to normal size.  Depending on the breed, she may not return into heat for many months. Small breed dogs tend to cycle every 3-4 months, whereas large and giant breeds can take up to 12-18 months to return to heat.  The average is usually 2 cycles per year.

You will have to closely monitor your dog when she is outdoors if you don’t want her bred.  I’ve had clients claim that neighboring dogs have jumped fences to breed their dog, so she’s not safe outside by herself.  I would also avoid interaction with male dogs even when on leash, as your dog may react aggressively to any dogs sniffing around her now.  (We all get cranky on our periods!) Though some dogs have very little bleeding, some will bleed quite heavily.  Pet specialty stores sell Velcro ‘diapers’ made specifically for dogs, to prevent staining and damage to your floors and furniture.  You should wait at least 2 weeks after the bleeding stops before scheduling her spay.  If you are planning to breed your dog, it is not recommended to breed on the first heat.  Please contact your vet for more information on when to breed, what to expect and how to prepare for whelping and caring for newborn pups.