Blog
 » 
Spay and Neuter
 » 
Side Effects of Spaying a Female Dog Explained

Side Effects of Spaying a Female Dog Explained

Spay and Neuter

X min read

Owners

Learn the common and rare side effects of spaying a female dog, including weight gain, hormonal issues, and recovery risks.

By 

Sustainable Vet Group

Updated on

October 20, 2025

.

Side Effects of Spaying a Female Dog Explained

Spaying a female dog involves surgically removing her ovaries and often her uterus to prevent reproduction and heat cycles.

It’s a routine procedure that supports population control and can lower certain health risks. Yet, it also changes the female dog’s hormonal balance, which may lead to specific side effects worth understanding.

  • Purpose of Spaying: It prevents unwanted litters and reduces risks of uterine infections or mammary tumors, making it a responsible medical decision.
  • Why Owners Ask About Side Effects: Many pet parents want to know how their female dog’s behavior, weight, or health might change after surgery.
  • Need for Balanced Information: Knowing both benefits and possible risks helps owners prepare for proper recovery and long-term care.

While spaying offers many health advantages, being aware of its possible side effects allows you to make an informed, caring choice for your female dog’s well-being.

Why Spaying Is Done in Female Dogs

Spaying a female dog is a preventive surgical procedure done for both medical and behavioral reasons. It not only stops reproduction but also shields the female dog from serious health problems and hormonal disorders later in life.

Understanding its benefits helps set the context before exploring possible side effects.

  • Prevents Unwanted Pregnancy: Spaying ensures no accidental litters occur, reducing the burden on animal shelters and preventing stray overpopulation. It also prevents stress on female dogs caused by repeated heats and pregnancies.
  • Eliminates Pyometra Risk: Pyometra, a severe uterine infection, is common in older unspayed females and can be fatal. Spaying completely removes this risk by removing the uterus.
  • Reduces Cancer Incidence: It lowers the likelihood of ovarian, uterine, and mammary tumors, particularly when performed before the first heat cycle.
  • Improves Behavior: Spayed female dogs are calmer, less aggressive, and less likely to roam, as they no longer experience hormonal surges linked to mating instincts.
  • Promotes Population Control: Responsible spaying supports animal welfare by preventing the birth of puppies that may not find homes.

Knowing these benefits highlights why spaying remains a responsible choice before discussing its side effects.

Immediate Surgical Side Effects of Spaying a Female Dog

Although spaying is common, it’s still a major surgery involving anesthesia and tissue removal. Some short-term surgical side effects can appear right after the operation and need careful monitoring for a smooth recovery.

  • Anesthesia-Related Complications: Some female dogs may show mild sensitivity to anesthesia, such as delayed waking, nausea, or low body temperature. Pre-surgical exams reduce these risks.
  • Bleeding and Hematoma Formation: Slight internal or external bleeding is normal but can worsen with excessive movement. Following rest instructions prevents strain on sutures.
  • Incision Infections: Redness, swelling, or discharge around the surgical site are warning signs. Proper hygiene and prescribed antibiotics help avoid infection.
  • Herniation After Surgery: Active female dogs that jump or run too soon can cause tissue bulging near the incision. Using an Elizabethan collar and crate rest helps prevent it.
  • Slow Recovery: Female dogs with low immunity or poor nutrition may take longer to heal, making rest, hydration, and wound care essential.

With proper care and veterinary guidance, most surgical side effects resolve quickly, allowing the female dog to recover without long-term complications.

Metabolic and Weight-Related Side Effects of Spaying a Female Dog

One of the most common long-term side effects of spaying a female dog is weight gain. The hormonal and metabolic changes following surgery affect calorie use and fat storage, increasing the risk of obesity.

  • Reduced Metabolism: The removal of reproductive hormones slows metabolism by about 15–25%. This means the female dog burns fewer calories at rest compared to before surgery.
  • Higher Appetite: Many spayed females develop an increased appetite as estrogen, which helps regulate hunger, is no longer present.
  • Lower Energy Levels: Some female dogs may show reduced interest in play or exercise after surgery. Regular activity is necessary to maintain fitness and prevent muscle loss.
  • Risk of Obesity-Related Diseases: Excessive weight can lead to arthritis, diabetes, and heart disease, especially in medium and large breeds.
  • Preventive Nutrition: Switching to a calorie-controlled or weight-management diet and scheduling daily walks helps balance the reduced metabolic rate.

Managing diet and exercise after spaying is essential to prevent obesity and support long-term joint and heart health.

Urinary and Bladder-Related Side Effects of Spaying a Female Dog

Hormonal changes after spaying can sometimes affect bladder control and urinary tract health. While these issues are not common, some breeds or older females are more likely to experience them.

  • Urinary Incontinence: Due to reduced estrogen, the urethral sphincter weakens, leading to urine leakage during sleep or relaxation, especially in middle-aged or older female dogs.
  • Higher Risk of UTIs: Hormonal changes may alter the urinary tract’s natural defenses, making infections more likely. Symptoms include frequent urination, odor, or discomfort.
  • Influence of Breed and Size: Large breeds such as Dobermans, Boxers, and Rottweilers are more prone to incontinence after spaying compared to smaller female dogs.
  • Age at Spay Surgery: Early spaying (before full maturity) slightly increases the risk of urinary complications. Timing should be discussed with a vet based on breed and health.
  • Treatment and Prevention: Most urinary issues can be managed with hormone therapy, bladder-strengthening medications, and maintaining ideal body weight.

These urinary side effects are usually mild and treatable, especially when identified early and managed under veterinary supervision.

Orthopedic Problems and Joint Disorders After Spaying a Female Dog

One of the lesser-known side effects of spaying a female dog too early involves bone growth and joint development. Hormones like estrogen play an important role in closing growth plates and maintaining joint stability, so removing them too soon can lead to skeletal imbalance.

  • Delayed Bone Plate Closure: Estrogen helps close growth plates at the right time. When spaying occurs before maturity, bones continue to grow longer than normal, affecting limb alignment and strength.
  • Higher Risk of Hip Dysplasia: Large and giant breeds are particularly prone to hip joint instability when spayed before full growth, increasing long-term arthritis risk.
  • Cruciate Ligament Tears: Early spaying is linked to weaker ligament support around the knee, making ACL (cranial cruciate ligament) tears more common during adulthood.
  • Patellar Luxation: Changes in limb structure can lead to kneecap displacement, especially in breeds already predisposed to it.
  • Breed Sensitivity: Labradors, Golden Retrievers, and German Shepherds show higher orthopedic vulnerability due to delayed bone maturity post-spay.

Delaying spaying until skeletal maturity, especially in large breeds, reduces these orthopedic side effects and supports lifelong joint health.

Long-Term Health Risks and Cancers After Spaying a Female Dog

While spaying protects against many reproductive cancers, studies suggest that it may slightly raise the risk of certain other cancers. These potential side effects of spaying a female dog depend largely on breed, genetics, and age at the time of surgery.

  • Osteosarcoma (Bone Cancer): Large and giant breeds may face higher bone cancer risk when spayed early, likely due to extended bone growth linked to hormone loss.
  • Hemangiosarcoma (Blood Vessel Cancer): Some research shows increased rates in spayed females, especially older female dogs, although findings vary across breeds.
  • Lymphoma: Hormonal shifts and immune system modulation after spaying might slightly influence lymphoma development in certain breeds.
  • Hormonal Imbalance Connection: Removing ovaries permanently changes estrogen and progesterone levels, which can affect cell regulation and immunity.
  • Timing Matters: Delaying spay surgery until adulthood may balance cancer protection and hormonal stability for some breeds.

Veterinarians now recommend breed-specific timing to minimize these long-term health risks while preserving the key benefits of spaying.

Hormonal and Endocrine Side Effects of Spaying Female Dogs

The ovaries produce several hormones that influence metabolism, immunity, and coat health. Once removed, hormonal balance shifts, leading to some of the subtler side effects of spaying a female dog, particularly in middle-aged females.

  • Elevated Luteinizing Hormone (LH): Without ovarian feedback, LH levels rise significantly. Chronic elevation may cause skin sensitivity, behavioral changes, or vulvar atrophy.
  • Thyroid Function Changes: Reduced estrogen can influence thyroid hormone activity, sometimes leading to mild hypothyroidism, which causes lethargy and coat dullness.
  • Immune System Shifts: Hormonal loss may reduce natural immune modulation, slightly increasing inflammation or allergic reactions.
  • Coat and Skin Texture Alterations: Some female dogs develop thicker or softer coats due to hormone changes, particularly in breeds like Spaniels and Setters.
  • Metabolic Disorders: In rare cases, long-term hormonal imbalance may contribute to diabetes or adrenal gland dysfunction.

While not every female dog experiences these endocrine effects, regular hormone and thyroid screening after spaying helps maintain long-term balance.

Behavioral Changes After Spaying a Female Dog

Behavior is one of the most noticeable areas affected by spaying. While many behavioral changes are positive, such as reduced aggression or roaming, a few side effects of spaying a female dog may involve anxiety or shifts in social confidence.

  • Reduced Roaming and Aggression: Without a hormonal drive to mate, most females become calmer and less likely to escape or fight with other dogs.
  • Lower Dominance and Heat-Related Behavior: Spayed females no longer show irritability or mood swings linked to estrus cycles, leading to a more consistent temperament.
  • Possible Fear or Anxiety Increase: Some female dogs may become slightly more anxious or timid after hormone removal, particularly if surgery occurs before social maturity.
  • Changes in Play and Socialization: Reduced hormone levels can alter how female dogs interact with males or respond to environmental stress.
  • Behavioral Support Post-Surgery: Positive reinforcement and stable routines help maintain confidence and prevent fear-based behaviors.

Overall, most behavioral outcomes are beneficial, but early behavioral support ensures emotional stability after surgery.

How Age, Breed, and Size Affect

The impact of spaying is not the same for every female dog. Age, breed, and size play major roles in determining how your female dog’s body and hormones respond after the surgery.

  • Age at Spay: Early spaying (before six months) may increase orthopedic and urinary risks, while delayed spaying (after full maturity) reduces joint issues but keeps short-term heat cycles.
  • Breed-Specific Differences: Large breeds like Labradors, Shepherds, and Golden Retrievers show stronger links between early spaying and joint or cancer risks compared to smaller breeds.
  • Size-Related Metabolic Variations: Smaller female dogs often recover faster and show fewer metabolic slowdowns, while larger breeds require more time and activity management.
  • Hormonal Development Period: Waiting until after the first or second heat can help balance bone growth and hormonal maturity, especially in giant breeds.
  • Health Condition Factors: Female dogs with chronic conditions such as diabetes or thyroid imbalance may need customized timing.

Discussing ideal spay timing with your vet ensures the best balance between health protection and minimal side effects.

How to Reduce Side Effects of Spaying a Female Dog

Even though side effects of spaying a female dog can occur, most can be prevented or minimized with proper care and proactive management. Responsible recovery and long-term monitoring help maintain a healthy life post-surgery.

  • Adjust Diet and Exercise: After spaying, reduce calorie intake by about 20% and include daily walks to prevent obesity and joint strain.
  • Monitor Wound Healing: Keep the incision clean, prevent licking, and watch for redness or swelling during the first 10–14 days.
  • Regular Vet Visits: Schedule annual blood work to monitor hormone and thyroid levels, especially in aging female dogs.
  • Support Hormonal Balance: Discuss natural hormone-support supplements or treatments if your dog shows signs of urinary or coat changes.
  • Modern Alternatives: Some owners consider ovary-sparing spays or hysterectomy-only options, which maintain partial hormonal balance while preventing pregnancy.

With careful follow-up and lifestyle management, most female dogs enjoy full, healthy lives after spaying with minimal complications.

Comparing Risks vs Benefits of Spaying Female Dogs

Spaying offers both major advantages and possible side effects, and understanding this balance is key for every responsible female dog owner. The benefits usually outweigh the risks, but the timing, breed, and overall health of your female dog make a significant difference in outcomes.

  • Key Benefits: Prevents unwanted pregnancies, protects against pyometra and reproductive cancers, and improves behavioral stability. It also supports population control, especially in high stray areas.
  • Major Risks: Includes metabolic slowdown, orthopedic issues in early spays, and rare urinary incontinence or hormonal imbalance. Some breeds may show higher risk for specific cancers if spayed too early.
  • Individual Variation: Age, breed, weight, and genetic background influence how a female dog reacts after surgery. No single spay recommendation fits all.
  • Veterinary Consultation: Personalized veterinary advice helps decide the right spaying timing to minimize health complications while maintaining hormonal balance.
  • Evidence-Based Approach: Relying on scientific studies and breed data ensures your choice supports both longevity and comfort.

Weighing pros and cons with your vet allows for an informed decision that protects your female dog’s health at every stage of life.

Conclusion

Spaying is a vital part of responsible pet ownership, offering clear health and behavioral benefits when done at the right time. Yet, it also comes with certain short-term and long-term side effects that every owner should understand.

  • Short-Term Effects: Pain, minor swelling, and temporary tiredness are normal and fade within a few days.
  • Long-Term Considerations: Hormonal changes may affect metabolism, joints, or urinary health depending on breed and spay age.
  • Importance of Timing: Choosing the right age helps minimize orthopedic and endocrine complications, especially in large breeds.
  • Ongoing Care: Balanced nutrition, regular exercise, and periodic veterinary monitoring ensure your female dog remains healthy for life.

When guided by veterinary advice, spaying remains a safe and beneficial choice that supports your female dog’s longevity, comfort, and overall well-being.

FAQs

What are the most common side effects of spaying a female dog?

The most common side effects include mild weight gain, changes in coat texture, and rare urinary incontinence in older females. Temporary fatigue, soreness, and reduced appetite may occur immediately after surgery. With proper care, most of these issues are short-term and easily managed through diet and exercise.

Does spaying always lead to weight gain?

Not always. Weight gain happens when calorie intake isn’t adjusted after surgery. Spayed dogs have slower metabolism, so reducing food portions by 15–25% and maintaining regular exercise can prevent obesity. Many spayed females stay fit and energetic with balanced nutrition and daily activity routines.

At what age should I spay my dog to avoid health risks?

Timing depends on your female dog’s breed and size. Small breeds can be safely spayed around 6–9 months, while large and giant breeds benefit from waiting until 12–18 months for full bone development. Your veterinarian can help determine the ideal timing to reduce orthopedic and hormonal risks.

Can spaying affect my dog’s behavior?

Yes, spaying can influence behavior. Most dogs become calmer, less aggressive, and less likely to roam. However, a few may develop mild anxiety or fear-based behaviors, especially if spayed very young. Providing consistent training, enrichment, and reassurance helps maintain balanced behavior after the procedure.

What symptoms should I watch for after spay surgery?

Monitor for redness, swelling, or discharge at the incision site, as these may signal infection. Also watch for vomiting, loss of appetite, or lethargy lasting more than 48 hours. If your dog shows difficulty urinating or walking, contact your veterinarian immediately for examination and follow-up care.

Get a Free Poster

Enhance your workspace with a high-quality radiographs reference poster, designed for veterinary professionals. This free physical poster will be shipped directly to you—just fill out the form to request your copy.

Related posts

Get a Free Poster for Your Clinic

Enhance your workspace with a high-quality radiographs reference poster, designed for veterinary professionals. This free physical poster will be shipped directly to you—just fill out the form to request your copy.

We'd love you to
Join Us!

Enter Your Details Below to Receive Your Information Pack

100% safe & secure. Your details are never shared or sold.

Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.

Taking Great TPLO Radiographs

Click Below to Watch Live Video Demos

We'll send you a Free Wall Poster with all the steps

Now that you are a pro at TPLO rads

Let's take your infection control to the next level

Watch these videos!

Step #1

Getting Ready

Ensuring a clean surgical field starts with proper skin preparation. This video demonstrates the best practices for:

  • Shaving the patient – Achieving a close, even shave while minimizing skin irritation
  • The Dirty Scrub – The initial skin prep step to remove surface debris and reduce bacterial load before the sterile scrub.

Following these techniques helps reduce infection risk and improve surgical outcomes. Watch the video to see how it’s done effectively!

Step #2

Reduce Your Risks

Many surgeons are shocked to find out that their patients are not protected from biofilms and resistant bacteria when they use saline and post-op antibiotics.

That’s Where Simini Comes In.

Why leave these risks and unmanaged?  Just apply Simini Protect Lavage for one minute. Biofilms and resistant bacteria can be removed, and you can reduce two significant sources of infection.

Step #3

Take the Course

Preventing surgical infections is critical for patient safety and successful outcomes. This course covers:

  • Aseptic techniques – Best practices to maintain a sterile field.
  • ​Skin prep & draping – Proper methods to minimize contamination.
  • ​Antibiotic stewardship – When and how to use perioperative antibiotics effectively.

Stay up to date with the latest evidence-based protocols. Click the link to start learning and earn CE credits!

Get Your
Free Poster!

Enter your information below, and we’ll ship it to you at no cost.

Do you want to customize it?

How many would you like?

About you

Shipping information

100% safe & secure. Your details are never shared or sold.

We will work on your request shortly.
Oops! Something went wrong while submitting the form.
What’s your role in animal care?

Tell us who you are so we can guide you to the most relevant information.