We have two kittens that are going to be outdoor cats. We've had them closed up in the garage with the mom (the mom has just been spayed) for 4 months. We already found homes for the others, but these 2 are going to remain here. There are fields on our property where they're going to live. We think it would be a good idea to have them spayed/neutered (1 male, 1 female) before letting them out since there are a few other cats that are field cats. I found out that they can be spayed at 4 months, but it is advised that the cat is 3.5-4 pounds first. I always heard that they should be 6 months. The girl is pretty small - I have a scale that I can weigh her on. I'd like to wait a bit, but the cats are anxious to be out. I'm afraid of her getting pregnant, or us not being able to catch her again. She is pretty tame though - we've successfully trapped and spayed 3 other outdoor cats. How soon can she get pregnant? My Maisey didn't go into heat until almost a year old.