my cat has a big stomach.

Question
My girlfriend and I recently took in a mom and her kittens. We found the kittens homes but we couldn't find the mom a home so we kept her. We also have to other male cats outside, and recently I have noticed the female cats stomach getting big.  She is skinny every where else except her stomach and her nipples look normal.  Is there some kind of disease cats get that make their stomachs big or is she pregnant again?

Answer
Hi Charles,

Female cats can, and do, go into heat again as soon as the last litter of kittens is weaned.  But whether or not she did depends on what climate you live in.  Cats generally stop mating when the weather gets cold; here in So. California we get kittens right up through Christmas and some stragglers after that.  Its entirely possible that she's pregnant again and the nipples still look normal because she's not ready to give birth just yet.  Off hand I believe they start to become engorged about a week before birth, by which time mom is quite large.
There are other medical conditions that could cause the stomach area to be bloated such as intestinal parasites (worms).  Being an outdoor cat it would be easy for her to pick up something like that.  Don't try de-worming her, though, until you know whether or not she's pregnant, it could harm the kittens.
If you want my opinion I think the odds are that you'll be having kittens around again in the not to distant future.  A cat,s gestation is about 9 weeks so see if that jibes with when the last kittens were weaned and/or taken away from her.  Prepare any area where she can safely have the kittens which is warm and quiet--you probably should start keeping her in as she gets bigger and closer to giving birth.  She also needs a lot more food, the kittens and breast feeding take a lot of her reserves.  Other than that I leave it to the mom, especially if she's done it before she knows best what to to.