Two overlapping things come to mind as to why a cat looks pregnant but isn’t: a disorder which causes the stomach to be distended and a medical condition called ascites.
A swollen or bloated abdomen can be caused by a range of conditions as follows:
- Eating fermented foods;
- Worm infestation, in kittens particularly;
- Cushing’s disease;
- Bowel obstruction;
- Bowel obstruction;
- Bladder outlet obstruction;
- Abscessed uterus;
- Acute gastric dilatation;
- Heart failure and
- Feline infectious peritonitis (FIP).
All of these often give cats a pot-bellied appearance similar to being pregnant. It is quite a long list, isn’t it? The default reaction by a cat owner would be concern and to make a veterinary appointment asap.
When an abdominal swelling comes on gradually over several days or even weeks it is most likely due to ascites which describes a condition in which fluid accumulates in the abdomen. The common reason is feline infectious peritonitis. Other causes might include a right-sided heart failure and kidney disease. A bacterial infection is called septic ascites.
Ascites can be caused by increased pressure in the veins of the abdomen. It might also be caused by decreased protein synthesis by the liver. This causes fluid to leak out of the blood vessels. Cats have a swollen or bloated abdomen.
Right-sided heart failure is less common than left-sided failure. Pressure backs up in the veins causing heart failure due to fluid backup in the circulation. There is fluid beneath the skin of the abdomen and swelling of the limbs. Fluid may build up in the abdominal cavity causing a pot-bellied appearance. Kidneys retain salt and water which can make the fluid retention worse.
The source of this information is: Cat Owner’s Home Veterinary Handbook.
The Internet also says that a swollen abdomen may be due to cancer or an infection. Of course, a cat might be overweight but the overall appearance is slightly different. When a cat looks as if they’re pregnant they have a swollen abdomen as opposed to an overall increase in apparent size. That’s why I would discount the idea of being overweight is a reason for a cat looking as if they are pregnant when they are not.
What to do?
As you can no doubt imagine, you have to see a veterinarian. Some of these conditions are serious such as FIP. I think that it is unwise for me to talk about treatments as I am not a veterinarian. All I can do is describe the condition from a good reference and then it is up to the owner to seek professional advice.
SOME MORE ON CAT HEALTH DIAGNOSIS – note: beware of self-diagnosis. It can be dangerous unless you are very competent.