My female puppy has suddenly become unsettled and I’ve noticed some bleeding. Could this mean she’s in heat, and is it normal at her age? How long will this last, and what can I do to keep her comfortable?
You may be worried the first time you notice changes in your female dog. She may suddenly seem restless, have a swollen vulva, or you might spot blood on her bedding.
These concerns are very common. Coming into heat (also called being “in season”) is a normal part of development for unspayed female dogs.
Your dog may show no obvious signs they’re in season. Some dogs may show a few while others may show many.
Most female dogs come into season around twice a year. The first season can happen from 6 months of age, depending on her size.
Every dog is different and the age of their first season and length of time in between seasons will vary.
Cycles may be influenced if your dog spends time with other unneutered females.
A season usually lasts around 2-4 weeks and during this time, a dog is fertile and could become pregnant if she mates with an unneutered male dog.
Our expert advice
Most female dogs come into season around twice a year. A typical heat lasts around two to four weeks and keeping her safe while helping her feel comfortable at home is key during this period.
What age does a puppy go into heat?
Most female dogs have their first heat between 6 and 12 months of age. Smaller breeds often come into season earlier, sometimes as young as six months, while larger and giant breeds may not have their first heat until they are 12 to 24 months old. If your puppy hasn’t had her first heat by the age you would expect for her size, your vet can offer reassurance.
Common physical symptoms of a female dog in heat
Physical signs are often the first thing owners notice. Here are more of what to look out for:
- Watery, pink or bloody discharge from vulva which you may spot on the floor or on bedding
- Enlarged, swollen vulva
- Increased licking of genital area
- Passing small amounts of urine more frequently to leave her scent, communicating she’s fertile
Common behaviours of a female dog in heat
Hormonal changes can affect behaviour and appearance. Here are a few behaviours to look out for:
- Increased interest or friendliness towards male dogs
- Avoiding other dogs approaching, they may tuck their tail between their legs if a dog comes close
- She may show humping type behaviour due to surge in hormones
- Gathering toys into her bed
- She may become less interested in eating her food
- Becoming less responsive off lead
- Restless, anxious, seeking more companionship or having more time alone
How long is a dog in heat?
A season usually lasts around 2 to 4 weeks, although this can vary between dogs. Vets often describe four stages in a heat cycle:
- Proestrus, when swelling and bleeding begin
- Oestrus, when your dog is fertile and most attractive to male dogs
- Dioestrus, when fertility ends
- Anoestrus, the resting phase between seasons
You don’t need to remember these stages. It’s just helpful to know that bleeding often happens earlier in the cycle, and fertility peaks partway through.
Keeping a note of dates and signs can make future seasons easier to manage.
How to comfort a dog in heat
Keeping your dog comfortable starts with reassurance. Many dogs benefit from a quiet place to rest, gentle enrichment, and familiar routines.
Some dogs may seek extra affection, so offering calm companionship can help them feel safe and settled.
Avoid punishing any behavioural changes. These are just caused by hormones, not disobedience.
Puzzle toys or training games can help keep your dog’s mind busy in season, especially if they’re not having as much physical exercise outside during this time.
How to stop a dog in heat from bleeding (managing mess safely)
It’s not possible to stop a dog from bleeding during heat, but there are ways you can manage the mess.
You may wish to dedicate a specific area like a crate or space in the home for your dog when they’re bleeding. If you do, make sure you familiarise her with this space before seasons, so she feels comfortable.
Washable bedding, old towels, or blankets can help protect furniture. Some dogs are even happy to wear dog sanitary pants – just make sure they’re comfortable first.
If you use any hygiene products, introduce them gently and positively, ideally before the season starts.
The goal is to keep your dog clean and comfortable, not to stop the bleeding completely.
Do dogs get period cramps?
Dogs don’t have periods in the same way humans do, but some may feel a little uncomfortable, especially early in the heat cycle.
This is usually caused by hormonal changes and vulva swelling. Signs may be - restlessness, clinginess, or seeking reassurance.
These signs are usually mild, but if your dog seems to be in a lot of pain, speak to your vet.
Keeping your dog safe during heat (preventing pregnancy)
During heat, it’s important to prevent contact with unneutered male dogs.
Keep your dog on a secure lead when out walking, ensure all walking equipment is in good working order, avoid off-lead areas, and never leave her unattended in the garden. Check that fences and gates are secure.
Even brief contact can lead to pregnancy, so careful supervision is key throughout the entire heat cycle.
When your dog shouldn’t be in heat (red flags)
Some signs aren’t normal and should prompt a call to your vet. These include:
- Very heavy or prolonged bleeding
- Discharge that looks thick, smelly, or unusual in colour
- Extreme distress or lethargy
Sudden changes in discharge or behaviour can sometimes mean there’s an infection present. If in doubt, it’s always best to seek advice.
If your dog hasn’t had her first heat by the expected age for her size, it’s worth checking with a vet.
Should I spay my dog?
Spaying stops heat cycles and prevents unwanted pregnancies. It can also have long-term health benefits for many dogs.
Vets normally recommend spaying after a season, not during heat, because surgery is safer when hormone levels are lower.
Your vet can help you decide the best timing based on your dog’s age, breed, and overall health, and whether it's more appropriate to wait until after the first season.
When to contact the vet
Contact your vet if you notice abnormal bleeding, signs of pain, unusual discharge, or anything about your dog’s behaviour that seems off.
Your vet can also advise whether your dog is in heat, if you’re unsure, or want to know how best to manage it.
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