🐾 Vet Guide 2025: Pregnancy Termination in Dogs & Cats by Dr Duncan Houston

Mismating—a surprise pregnancy in dogs or cats—is common, but deciding the right next step requires compassionate and informed veterinary care. In this 2025 vet-approved guide, Dr Duncan Houston outlines safe, effective, and humane pregnancy termination options for your female pet, and explains what to expect before, during, and after the procedure. 🐶🐱

🔍 Understanding Mismating

Pregnancy can occur unexpectedly: maybe you postponed spaying, an unplanned mating happened, or adoption paperwork was mistaken. Regardless, mismating is best handled with care. Avoid early “morning after” hormone treatments—they carry high risks. Instead, wait until pregnancy is confirmed before making decisions.

📅 Confirming Pregnancy

At around 30 days post-mating, a Witness Relaxin blood test can confirm pregnancy, much like a home test for humans. Once pregnancy is verified, explore termination and care options with your vet.

🌱 Option 1: Let Nature Take Its Course

Your pet may carry the pregnancy to term and deliver healthy offspring. But this route demands significant commitment:

• Prenatal care: veterinary check-ups, quality nutrition, and monitoring for complications.
• Labor support: recognizing warning signs and readiness to assist.
• Postpartum care: for mom and newborns.
• Finding good homes: for puppies or kittens—critical in combating pet overpopulation.

Given the overpopulation crisis, consider whether birthing is the responsible choice.

✂️ Option 2: Spay During Pregnancy

Spaying (ovariohysterectomy) during pregnancy terminates the gestation and prevents future ones. While it’s the most definitive option, it comes with increased surgical risks:

• Enhanced blood flow: Enlarged vessels in pregnancy increase bleeding risk.
• Longer surgical time: anesthesia and operative time increase.
• Higher cost: due to complexity and hospital stay.
• Extended recovery: may need longer hospitalization or belly support bandaging.

Discuss timing and risks with your vet. Early-stage spays (before advanced pregnancy) pose lower risks than late-gestation procedures.

💉 Option 3: Medical Abortion (Pregnancy-Sparing)

If future breeding is desired, medications can be used to terminate pregnancy during the second trimester (days 30–40). Protocols vary:

• Cabergoline or Bromocriptine + Prostaglandin:
  • Suppress prolactin (maintains corpus luteum).
  • Prostaglandin stimulates uterine contractions and breaks down the corpus luteum.
  • Cabergoline has fewer side effects than bromocriptine, but is costlier and newer in the U.S.
• Dexamethasone taper:
  • Steroid-based, 9–12 day oral course.
  • No hospitalization needed, minimal discharge.
  • Side effects: increased thirst/urination, panting.
  • Works best for dogs; limited data in cats.

Because medications can cause side effects and vaginal discharge, hospitalization for 5–7 days is recommended. Choose the protocol your vet is experienced with for the best outcome.

📋 Follow-up & Confirmation

Post-treatment checks are essential to verify termination:

• Relaxin blood test
• Ultrasound or abdominal X-rays
• Progesterone blood levels

Confirming completion ensures no retained fetal tissue remains.

⚠️ Avoid the “Mismating Shot”

High-dose estrogen injections were once used shortly after mating, but are now discouraged due to serious risks like:

• Pyometra (dangerous uterine infection): up to 25% incidence.
• Bone marrow suppression
• Prolonged heat and discharge

These treatments are outdated and unsafe—do not request them.

🤝 Discuss Your Pet’s Plan with Your Vet

Every pet is unique. Discuss with your veterinarian:

• Your pet’s health history and reproductive goals.
• Timeline since mating occurred.
• Your preference: spay vs. medical abortion.
• Cost, hospitalization needs, and follow-up care.

Early veterinary guidance ensures safer, less stressful outcomes.

📅 Summing Up Options & Timing

📞 How Ask A Vet Can Help

Need a second opinion or immediate guidance? Visit AskAVet.com or download the Ask A Vet App. Our team offers:

• Real-time advice from licensed vets
• Help choosing safe protocols
• Guidance on side effects and aftercare

Support and peace of mind are just a tap away. 📲

📌 Final Thoughts

Deciding to terminate a pregnancy is never easy. Whether you choose surgical or medical intervention, or decide to carry the pregnancy to term, make choices based on your pet’s health, your capacity to care, and ethical considerations. With careful veterinary oversight—especially via the trusted care of Ask A Vet—your female companion will receive the respectful, knowledgeable support she deserves.

Thank you for turning to veterinary expertise and compassion. For questions or to schedule follow-up care, contact your vet or our Ask A Vet team anytime. ❤️