Help! My Spayed Dog Acts Like She is in Heat! (Vet Answered)
This question has been answered by a vet
Veterinarian & Animal Behaviorist
With nearly two decades in veterinary medicine, Dr. Paola brings hands-on experience across multiple species. A graduate of the University of Guadalajara, she specializes in preventive care, animal welfare, and positive reinforcement training.
The Question
“Is it possible for my spayed dog (Lady Macbeth) to still have a cycle? Sometimes she seems like she is in heat (moody, humpy, lethargic)“ – Betty
Quick Info about Lady Macbeth
Hi Betty,
Once a dog has been spayed and both ovaries are completely removed, she should no longer go into heat. If Lady Macbeth is still showing signs that resemble a cycle, such as mood changes, mounting, or periods of low energy, one important possibility is ovarian remnant syndrome. This happens when a small piece of ovarian tissue is left behind during surgery. Even a tiny fragment can continue to release hormones, which makes the body behave as if it is still cycling.
To investigate this, your veterinarian may recommend blood tests to measure hormones like progesterone or Anti-Müllerian Hormone, ideally done when Lady Macbeth is showing these signs. Vaginal cytology may also be used, since the cells in the vaginal wall change in response to estrogen. If ovarian tissue is confirmed, the solution is a second surgery to remove the remnant, and this usually resolves the problem completely.
There are also other explanations worth considering. Contact with human estrogen creams, adrenal tumors that secrete hormones, or conditions like urinary tract infections or vaginitis can all mimic heat. Mounting and mood shifts can also be related to stress or social behavior rather than hormones, and lethargy may point to other health issues, such as thyroid disease. Because these possibilities overlap, a complete veterinary evaluation is the best way to uncover what is really happening and ensure Lady Macbeth gets the right care.
Best,
– Dr. Paola