Female cats that fail to mate will have symptoms of pseudopregnancy. Female cats with pseudopregnancy will have pregnancy-like symptoms such as red nipples and enlarged belly. Some female cats will also experience vomiting and loss of appetite, but these symptoms will not last. It lasts for a long time, usually disappearing 30-40 days after mating. After the pseudopregnancy disappears, the hormones in the female cat's body will return to normal, and she will then go into heat again.