When Do Boston Terriers Go Into Heat?

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Similar to humans, Boston Terriers also undergo a reproductive cycle that makes them receptive to mating. If you’re wondering when do Boston Terriers go into heat, we’ll look at how heating happens so you can plan breeding, spaying, or neutering times. 

When Do Boston Terriers Go Into Heat? 

Boston Terriers reach puberty and sexual maturity around 6 to 8 months. Around this time, Boston Terriers will experience its first heat cycle. They will undergo a heat cycle every 26 to 34 weeks, and it may last for up to 21 days. 

While heating naturally comes in Boston Terriers, it’s essential that you understand the cycle, what happens when your pet is in heat, and what we can do to help them. 

Boston terrier near buildings

Boston Terrier Heat Phases

A Boston Terrier will undergo the heat cycle twice a month. From there, the cycle may last for up to three weeks. While they can be sexually active throughout the year, Boston Terriers are most fertile at around 12 to 15 months, once they attain adulthood’s physical and behavioral maturity.

To better understand when Boston Terriers go into heat, we must learn about how the breed’s growth stages coincide with the heating cycle.

The reproductive cycle of Boston Terriers has 4 phases. Each stage comes with hormonal and physical changes, as well as differing signs of behavior.

  • Proestrus: The starting phase of the heating cycle that lasts for 7 to 10 days. Female dogs will discharge blood once the genital area swells, attracting mates. Despite peak estrogen levels, a female Boston won’t be receptive to pregnancy yet.
  • Estrus: This is the actual mating period that happens for 5 to 10 days. It’s the most fertile period since there will be a decrease in blood flow during the female genital discharge. Your Boston Terrier becomes willing to mate at this stage. 
  • Diestrus: This is the phase after the heat that lasts for 4 to 5 months. It’s the resting stage that makes female Boston Terriers not receptive to studs (male dogs) because they are no longer fertile.
  • Anestrus: This part allows the Boston Terrier’s body to prepare for the next cycle and possible pregnancy. Female dogs may not show interest in mating, although intact male dogs may still feel attracted to them.

Frequency and Duration of Heating in Boston Terriers 

Female Boston Terriers normally go into heat twice a year, about 6 months apart, each lasting for 2 to 3 weeks. 

Depending on your Boston Terrier’s health, it may take up to 18 months until the heat cycle becomes regular. In other cases, small breeds like Boston Terriers may go into heat 3 to 4 times per year. 

On the other hand, studs don’t have a sexual cycle. Instead, they would respond to female canines in heat any time of the year. Even with a 1.2% decline in sperm motility, studs can still feel attracted when females are in heat.

Signs of Heat

There are physical and emotional changes that can help notify you if your Boston Terrier is about to undergo the heating process. 

  • Overly affectionate 
  • Becomes more tired 
  • Becomes more aroused 
  • Restlessness or nervousness
  • Distracted
  • Tries to run away 
  • Swollen genital area 
  • Excessive licking of the genital area
  • Blood discharge may turn pinkish-tan
  • Increased urination 
  • Pays more attention to a potential mate 
  • Whining or crying 
Boston terrier lying on a pillow

What to Do When Your Boston Terrier Is in Heat 

Despite heat being a natural phenomenon in dogs, your Boston Terrier would want your help to help calm down and ease any discomfort. These are some tips to care for a Boston Terrier in heat.

  • Keep in-heat dogs away from other dogs: An unspayed Boston Terrier can get pregnant during her first heat, so make sure to keep an eye on her. If you have an unneutered Boston Terrier, it’s best to keep him away from female dogs.
  • Lock them up: Although Boston Terriers typically do not wander off, some dogs in heat tend to stray away. Avoid going outside or visiting dog parks where they can mate with other dogs. 
  • Boost appetite: Some female Boston Terriers may lose appetite when in heat, although you can entice them with delicious treats. However, make sure to provide a daily meal
  • Give extra attention: Cuddle and pet your Boston Terrier as it loves being in close contact with humans
  • Ensure comfort: Provide a comfortable and quiet space where your pet can rest. 
  • Keep your pet active: Get your Boston Terrier engaged using mental games and interactive toys. About 54% of dogs in America are overweight, so make sure to keep your pet healthy to ease discomfort.
  • Continue grooming: You can still bathe a Boston Terrier in heat or use wet wipes to remove blood on the skin. 
  • Be patient in frequent potty breaks: Your dog will have the urge to relieve herself more than usual. In addition, you may see drops of blood around. Don’t scold your pet, and just calmly reassure her while you clean.

Here are a few more common questions and answers for Boston Terrier’s and their heat cycle.

How to Stop Unwanted Pregnancies in Boston Terriers?

While veterinary abortion is an effective way to terminate the pregnancy, this is a risky procedure that can harm your Boston Terrier. The best way to avoid unwanted pregnancies is to spay female dogs and neuter male ones.

What’s the Breeding Age for Boston Terriers? 

Although Boston Terriers can mate once it starts the heating cycle, it would be best to wait for your pet to become physically mature at around 2 years old. In this way, there’s a better chance that the pregnancy will push through and your pet is in a healthier state. 


Boston Terriers may first experience heating at around 6 to 8 months old. From there, they would go into the heating cycle every 26 to 34 weeks. Watch for signs, monitor the duration, and make sure to provide the best care for your Boston Terrier.