1. Delivery of all kittens: The most obvious sign that a cat's labor is over is when all of the kittens have been delivered.
2. Expulsion of the placenta: After all the kittens have been born, the cat will usually expel the placenta, which is the organ that provides nourishment to the kittens during pregnancy. The placenta may look like a dark red or brownish mass.
3. Change in behavior: A cat in labor will often exhibit certain behaviors, such as pacing, panting, and crying. Once labor is over, these behaviors should subside and the cat may seem calmer and more relaxed.
4. Return to normal appetite: Cats may lose their appetite during labor, but it should return to normal once labor is over.
5. Nursing behavior: Once labor is over, the cat will start nursing her kittens, providing them with essential nutrition and antibodies.
It's important to monitor your cat closely during and after labor. If you have any concerns or notice any unusual signs, consult with a veterinarian.