Female dogs are "in heat" when they have entered the fertile part of their reproductive cycle. A heat lasts for 3 weeks on average and a dog will usually go into heat every 6 to 8 months.
Most breeds have their first heat at about 6 months old but it may be earlier or later.
A heat can usually be identified when there is some bleeding from the vagina, a swollen vulva or increased urination. Female dogs do not produce very much blood however, and in a small dog you may not even notice the bleeding.
Unwanted attention
The first thing you will notice if you have a bitch in heat is that she will attract un-castrated male dogs within a very large radius. Her behaviour will change too, so while she normally wouldn't let males mount her, she almost definitely will while in heat.
Additionally, male dogs will go to surprising lengths to get to a female in heat. While your bitch is in heat it's inadvisable to leave her unsupervised outside, and you'll need to keep her on the lead at all times while on walks. In general, other pet owners you encounter will be able to control their dogs, but the scent of a female in heat can cause aggressive behaviour in some dogs.
Tasty Tips
Bleeding
The second concern is bleeding. If your dog is producing enough blood to cause a mess you may want to restrict her to easy-to-clean, un-carpeted floors. Just leaving her outside is a bad idea unless you want her to have male visitors (and potentially puppies).
Unless you intend breeding, it is best to have her spayed. Spaying will prevent her from going into heat.
There is some debate about when it is best to spay your bitch. Some veterinarians will advise to let a dog have one heat while others will spay as early as 6 months. Ask your vet which course of action they think is right for your dog.
Related products
Hypoallergenic Medium Adult Dog Food
Science Plan Hypoallergenic Medium Adult dog food with Salmon is a gentle, science-led formula crafted for dogs with food sensitivities. Made with carefully selected, high-quality novel proteins and no grains, it’s tailored to minimise common triggers that can lead to skin and digestive discomfort.
Sensitive Stomach & Skin Small & Mini Adult Dog Food
Hill's Science Plan Sensitive Stomach and Skin Small & Mini Adult Dog Food with Turkey is a complete premium pet food for small breed adult dogs aged 1–6 years. This deliciously soft mousse is enriched with ingredients that support digestive health & skin care.
Puppy & Mother Tender Mousse Dog Food
Hill's Science Plan Puppy & Mother Tender Mousse Dog Food with Chicken is a complete premium pet food for puppies and pregnant or nursing dogs. Formulated with chicken and other specially selected ingredients, including minerals and antioxidants to support gut health and optimal growth, it comes in a soft mousse texture they'll love.
Perfect Weight Small & Mini Adult Dog Food
Hill's Science Plan Adult Small & Mini Dog Food with Turkey is a complete premium pet food for adult small dogs from 1 year old that are prone to weight gain or slightly overweight. This deliciously smooth mousse is formulated to deliver the appropriate amount of energy to support weight maintenance in adult dogs.
Related articles
Dog Bitten by a Snake? Clinical Symptoms & What You Should Do
Learn about snake bites on dogs, including clinical symptoms to look for, what to do if you think your dog was bitten, and treatment & prevention options.
What should I do about my overweight dog?
Dog obesity is a significant problem - learn more about helping your dog become trimmer and healthier through improved nutrition.
Are your Dog’s Bad Habits Stomach Churning?
Puppy, kitten and pet dieting, cat nutrition and dog nutrition information from Hill's Pet
Kidney Disease in Dogs: Causes, Signs & Treatments
Discover the causes, signs, and treatments of kidney disease in dogs and find methods of supporting your dog's kidney health. Learn more at Hill's Pet South Africa.
Put your dog on a diet without them knowing
Our low calorie formula helps you control your dog's weight. It's packed with high-quality protein for building lean muscles, and made with purposeful ingredients for a flavorful, nutritious meal. Clinically proven antioxidants, Vitamin C+E, help promote a healthy immune system.
Put your dog on a diet without them knowing
Our low calorie formula helps you control your dog's weight. It's packed with high-quality protein for building lean muscles, and made with purposeful ingredients for a flavorful, nutritious meal. Clinically proven antioxidants, Vitamin C+E, help promote a healthy immune system.