Are you thinking of breeding your dog? On the other hand, maybe you're worried that your intact dog could become pregnant?
Whatever the case may be, you're reading this article because you want to know when dogs can get pregnant. The answer is that dogs generally experience their first estrus cycle, the part of the reproductive cycle when they can fall pregnant, at around six months of age, and most dogs come into heat twice per year.
However, there are several other variables that affect when your canine companion can get pregnant, so let's take a closer look at the estrus cycle of female dogs and what this means for the possibility of puppies.
Signs Your Dog is in Heat
If you've never owned an intact female dog before, it can sometimes take a little while to work out when your pooch is in heat. The first sign your dog is in estrus (in estrus is basically another way of saying "in heat" or "in season") is swelling of the external vulva.
However, as this may not be immediately obvious, the earliest sign many owners notice is vaginal bleeding, which in some cases won't become apparent until several days after estrus has begun. Some animals only experience a small amount of discharge, others can have heavy bleeding. Your dog will also start paying a greater level of attention to her rear end, and may start licking the area.
Around 7 to 10 days into the cycle, this vaginal discharge changes to a watery, pinkish-red color. You may also notice that your female dog develops marking behavior when in heat. This means she frequently passes small amounts of urine containing pheromones and hormones which signal to any interested males that she will soon be ready to mate.
However, it's worth pointing out that while a female will become attractive to male dogs right from the start of her estrus cycle, she won't be ready to allow mating for another 7 to 10 days.
The Science of Dog Pregnancy
Most dogs reach sexual maturity around six months of age, but this isn't always the case. Smaller dogs often have their first estrus cycle at a slightly younger age, while giant breeds might be 18 months or even 2 years old before coming into heat for the first time.
The majority of dogs come into heat twice a year, roughly every six months, but this is far from a rigid timetable and can vary between breeds and between individual dogs. Smaller breeds can even cycle three times a year, while giant breeds may only come into heat every 12 or 18 months. It also takes up to two years for your growing female pooch to settle into regular cycles.
As a result of these many variables, there's no one particular season of the year that can be classified as "breeding season", as dogs come into heat based on their own internal cycle.
The heat cycle itself lasts for 2-3 weeks. Ovulation generally occurs when the vaginal discharge turns watery, usually after 7 to 10 days, and is when a female is at her most fertile and usually becomes receptive to males. However, ovulation can potentially occur earlier or later in the cycle than outlined, so working out the absolute best time to mate your dog can be a difficult task. Your veterinarian can help by conducting either a blood test or a vaginal smear test to determine the optimum time for mating.
Spaying Your Female Dog
If you're at all worried about your dog becoming pregnant, the best thing to do is to have her spayed before she reaches her first estrus cycle. Because there's no definite timeframe on when this will occur, most veterinarians recommend sterilization before your dog reaches six months of age. However, spaying can usually safely occur any time after eight weeks of age.
Spaying involves the removal of both the ovaries and the uterus. It's major surgery, and a procedure that some dog owners are hesitant to put their pet through. But there are plenty of good reasons why you should consider having your dog spayed:
Your pet will have a reduced risk of pyometra (a potentially fatal infection of the uterus) and mammary gland cancer
Spaying prevents unwanted litters and helps reduce the pet overpopulation problem
- You'll avoid the behavior changes, such as frequent urination and calling for mates, associated with a dog in heat
- You won't have to worry about dealing with males attracted to your dog in heat
- The cost of spaying a dog is much less than the cost of caring for a litter of puppies
Speak to your veterinarian to find out when is the best time to spay your pet. Your vet will also be able to take you through what the procedure involves and what you need to do to get your dog ready for surgery.
By a Labrador Retriever lover Tim Falk
Published: 03/02/2018, edited: 04/06/2020