When and How Often Do Labs Go Into Heat?
Female Labrador Retrievers usually go into heat every six months, though the exact timing can vary slightly depending on age, genetics, and overall health.
The first heat cycle typically happens between 6 to 12 months of age, and after that, most Labs settle into a regular pattern, about twice a year. Each heat (also called the estrus cycle) lasts around 2 to 3 weeks, during which the dog’s body prepares for potential breeding.
Labrador Heat Cycle
The heat cycle in dogs is not random. It follows a biological rhythm divided into four distinct phases, each marked by hormonal changes and behavioral cues. Knowing these helps owners handle the process calmly and confidently.
1. Proestrus (The Beginning – About 7–10 Days)
This is when the cycle begins. You may notice swelling of the vulva and a bloody discharge. Male dogs will start showing interest, but females are not ready to mate. Behaviorally, she might be more affectionate or clingy.
2. Estrus (The Fertile Period – About 5–10 Days)
This is the true heat phase, ovulation occurs, and the discharge may turn lighter in color. The female is receptive to males now, and this is when breeding can occur. If you not not planning a litter, supervision is critical during this time.
3. Diestrus (Post-Heat – About 2 Months)
Once the heat phase ends, hormones settle down. Whether or not she is pregnant, her body behaves as though she might be. This is when some dogs may show false pregnancy signs like nesting or enlarged nipples.
4. Anestrus (Rest Period – About 4 Months)
This is the quiet phase where her body rests and resets before the next cycle. It is the ideal time to focus on nutrition and overall health care.
How Often Do Labs Go Into Heat?
On average, Labradors go into heat every six months, but “average” doesn’t mean “exact.”
Some smaller Labs may cycle every 5 months, while others might take up to 8 months. Young females often have irregular cycles during their first year, as their bodies are still balancing hormones. Once they reach maturity (around 18–24 months), most Labs become consistent.
🩸 Key takeaway: Expect two heat cycles per year, roughly six months apart, but allow for slight variation.
When Do Labs Have Their First Heat?
Most female Labs have their first heat between 6 and 12 months old, though it can come as early as 5 months or as late as 14.
Larger-boned or heavier females often mature a bit later than smaller ones. Early or delayed cycles are usually normal, but if your Lab has not gone into heat by 18 months, a vet visit is wise to rule out hormonal or developmental issues.
How Long Does a Labrador’s Heat Last?
The entire heat cycle usually lasts 2 to 3 weeks, but visible signs, like discharge or swelling, may only appear for part of that time.
Here’s a simple breakdown:
| Stage | Approx. Duration | Key Signs |
|---|---|---|
| Proestrus | 7–10 days | Swelling, bloody discharge, attracts males |
| Estrus | 5–10 days | Receptive to mating, discharge lightens |
| Diestrus | ~2 months | Hormone stabilization |
| Anestrus | ~4 months | Resting phase |
Signs Your Lab Is in Heat
Recognizing the signs early helps prevent accidental breeding and keeps your dog comfortable. Look for:
- Swollen vulva
- Bloody discharge (color changes over time)
- Frequent licking
- Behavior changes (clingy or restless)
- Increased urination
- Attraction of male dogs
During this period, limit outdoor freedom and avoid dog parks; males can smell a female in heat from far away.
How to Care for a Labrador in Heat?
1. Keep Things Clean
Use washable dog diapers or heat pants to prevent messes inside the house. Clean her bedding daily and maintain a calm environment.
2. Manage Exercise and Stress
Light walks are fine, but avoid overexertion. Stress can disrupt hormonal balance. Skip training sessions during the most sensitive days if she seems distracted.
3. Protect from Unwanted Mating
Even the best-trained Lab can bolt if a male shows up. Keep her on-leash and supervised outdoors.
4. Nutrition and Hydration
Heat cycles can slightly affect appetite. Offer a balanced diet rich in omega-3s and lean proteins, and ensure constant access to clean water.
Spaying and Heat Cycles
Spaying eliminates heat cycles altogether and helps prevent certain health issues like pyometra (uterine infection) and mammary tumors.
Most vets recommend spaying after the first or second heat, but timing depends on individual health and growth rate. Always discuss this with your vet to balance health benefits and growth maturity.
Frequently Aksed Question(s)
How often do Labs bleed when in heat?
Typically once every six months, for about 7–10 days during the proestrus phase.
Do Labs get moody during heat?
Yes, hormonal changes can make them more affectionate, anxious, or withdrawn. It’s temporary and normal.
Can a Lab get pregnant in her first heat?
Yes, even though she is still young. Breeding during the first heat is strongly discouraged due to physical immaturity.
What if my Lab hasn’t gone into heat yet?
If she is over 18 months and has not had her first cycle, consult a veterinarian to rule out hormonal or developmental issues.