A video of a 12-year-old cat with a visibly moving stomach has left viewers on Reddit both amused and baffled—but the real answer, it turns out, had nothing to do with kittens.

The footage, shared by the cat’s owner under u/flimsy-throat-5602 on July 1, shows the cat’s belly undulating in a way reminiscent of fetal movements in pregnant animals.

“What is happening here?” The owner asked in the post, which has since been upvoted more than 12,000 times to date. The clip quickly gained traction on the subreddit r/cathelp, sparking speculation from fellow cat owners, many of whom guessed pregnancy or more serious illness. As the original poster clarified in a follow-up comment, neither was the case.

“Sorry I should have clarified in the post…12-year-old spayed female…Does not ever go outside…Still eating and drinking and using the box…Was not injured in any way that I’m aware of,” the owner wrote. “She is at the vet now! And she’s [definitely] not pregnant…”

The official diagnosis? Constipation.

“Blood work came back completely normal,” the owner added in a later comment. “Very, very slightly anemic. No trapped air in abdominal cavity. Basically, what we’re seeing in the video is peristalsis.”

Peristalsis refers to the wave-like muscle contractions that occur in the digestive tract and help move food through the digestive system. While it is a normal process, its visibility can sometimes alarm pet owners, especially when it appears as pronounced as in the video.

How To Spot Digestive Issues in Cats

Newsweek spoke with Dr. Aimee Warner, a veterinarian with Waggel, to better understand how constipation manifests in cats and how to recognize the warning signs early.

“Constipation can be subtle, so pay attention to litter-box positions and the body language of your feline friends,” Warner told Newsweek. “When a cat has not had any stool—or had only small, hard, dry ‘pebbles’ of stool—within 48 hours, that is your first red flag.”

Warner noted that owners might also observe excessive squatting in the litter box with little to no result, sometimes accompanied by a plaintive meow or a quick retreat from the box.

“Check the clumps: fewer or smaller of them (in clumping litter) indicate lower production,” she said.

She also warned that spill-over symptoms can indicate more serious issues.

“A constipated cat will begin to skip meals, vomit water or food, or become very withdrawn at the pain of a distended colon,” Warner added. “Others lick or bite the base of the tail or belly in response to pressure, and you can detect a firm, sausage-shaped bulge if you lightly stroke the belly with your hand—though a proper palpation is best left to your veterinarian if your cat objects.”

The veterinarian emphasized the importance of early intervention.

“If any of these symptoms persist beyond one day, or if accompanied by vomiting, lethargy, or pain in the abdomen, get to the vet as quickly as possible,” she said. “Early treatment avoids development of complete blockage and megacolon, both much more difficult to treat than simple constipation treated early.”

Newsweek reached out to u/flimsy-throat-5602 for more information via Reddit.

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