Ovarian remnant syndrome (ORS) is the return of heat signs in a bitch that has been spayed, because some functional ovarian tissue was left behind. It is uncommon but frustrating for owners, it can lead to uterine stump pyometra and reproductive tumours, and on the NAVLE it tests whether you can read the hormone tests correctly and plan the surgery.
Key facts
Ovarian remnant syndrome at a glance- Species and system: spayed female dogs (also cats); reproductive and endocrine.
- Cause: functional ovarian tissue left at the original ovariohysterectomy (OHE) or ovariectomy (OVE); surgical error is the usual explanation.
- Classic presentation: a spayed bitch with vulvar swelling, serosanguineous discharge and males showing interest, months to years after surgery.
- Typical side: the right pedicle is involved more often than the left in dogs.
- Best screening test: anti-Müllerian hormone (AMH) and progesterone on one serum sample.
- Treatment: surgical removal of the remnant (laparotomy or laparoscopy) with histopathology of everything removed.
- Zoonotic or reportable: no.
What's inside
13 sections in the full guide- Key facts
- How the NAVLE tests this
- Cause and pathophysiology
- Clinical signs
- Diagnosis
- Differential diagnoses
- Treatment and management
- Complications of an untreated remnant
- Prevention
- Prognosis
- Quick review
- Test yourself
- References
The full guide also has 5 tables, 2 figures, 3 self-test questions and 13 references, available to NAVLE members.
Read the full study guide
The full guide is part of every NAVLE plan, with diagnosis and treatment tables, figures, a quick review and self-test questions. Start a free trial to try the question bank, or log in if you are already a member.