Can a Spayed Cat Grow Ovaries Back?

1 Overview

As the weather turned cold, many cats began their mating season, yowling at night and raising their hindquarters, disturbing the family’s rest and worrying about neighbors’ complaints. At noon, a thin young woman came to the clinic carrying a cat carrier.

She took out a calico cat, small in size and clearly a female. The kitten lay on the exam table, nervously looking around the room, wanting to hide.

Before I could speak, the woman said, ‘Doctor, my cat was spayed at another hospital last year, but recently she cries at night again – is she in heat? My family has been complaining about the noise the last two days.’

After neutering, some male cats still mount, with the little rear twitching – that is normal. But a female cat that has been spayed should definitely not go into heat again after six months. If she does, first suspect that the ovaries were not fully removed.

But whether by ultrasound or MRI, residual ovarian tissue is very hard to find. Still, since she was here, we tried an ultrasound. Unexpectedly, something resembling an ovary was found behind the left kidney. With heat signs plus a suspected ovary, it was basically ovarian remnant syndrome.

The woman asked me again, ‘Doctor, when she was in heat last time I asked that doctor, and he said the ovaries might have grown back. Is that possible?’

I almost said: Are ovaries like a gecko’s tail, growing back after being cut? But I held back.

Once the ovaries are fully removed, no new ones grow. If they seem to ‘grow back,’ it must be residual ovarian tissue.

We scheduled surgery with the owner for abdominal exploration. I share this case not to make anyone anxious about spaying, lest they avoid a needed procedure.

Rather, I want to remind owners that if a spayed female cat or dog shows heat after spaying, consider ovarian remnant syndrome. Removed ovaries do not grow back.