How Can You Tell If A Cat Is Spayed?

Hi! I am new here and I have a question. In October a cat showd up at my house and hasn't left since. I think someone dumped her. She is fed the same as my three other cats, yet when you pick her up she is really quite heavy. When you look at her, she doesn't look fat though. I am not sure if she pregnant or has worms. I am going to take her to the vet next week, but does anyone know if you you can tell if a cat is spayed or not?
Thanks!
Beth

Beth the only way you can tell- and usually a vet has to do this, is to shave the belly and look for a tattoo or a scar. Nowadays, if they spay or neuter a feral cat, they take just the edge of the tip of one ear to mark that they have been "fixed." Thank you for taking in this lost one. Let us know what the vet says.

My cat was stray but because she was already declawed (no, I didn't do it to her!), I assumed she was also spayed. About 2 weeks after taking care of her, I noticed a few behaviors; urinating and deficating outside of the litter box which she had used religously for 2 weeks, making loud calling noises, wanting excessive attention, placing her butt towards me (thanks, but not interested - lol), and running around my apartment like a mad cat. I took her to the vet and they shaved her belly and found no scars. About 2 weeks later, I had her spayed and she's been nothing but a relatively well-behaved and quiet cat. I agree. Take her to the vet for a check-up.

I took her to the vet- they think she might be pregnant! They aren't sure though and said that I would be able to tell in about 10 days because she'd start to get really fat. I will keep you posted!!
-Beth

Are you keeping her inside? You should bring her inside and begin to make friends with her and provide her a nice safe room where she will feel confident enough to have her kittens in a birthing box. Doesn't surprise me she is pregnant, most outside cats not spayed are.

I already have three cats and two dogs that live in the house and if I brought the other cat in, there would be a huge uproar. Not to worry- Cindy (the cat) has a nice big cat house out on my porch. It should be pretty warm and she enjoys going into it and snoozing. I put her in there at night. She is very friendly so I don't think I'll have any problems with helping her should she be pregant.
I'll keep you posted still! Thanks for your help!
-Beth :split: