How to let the cat expel the placenta:

1. You can first let the cat expel the placenta on its own. Generally, the placenta will be expelled with the birth of the kitten during the birth process.

2. Inject an appropriate amount of oxytocin into the cat, and use the effect of oxytocin on the uterus to help the cat expel the placenta.

3. If the cat still fails to expel the placenta through the above two methods, laparotomy may be considered.

Hazards of unexpelled cat placenta:

1. It will cause cats to suffer from metritis, seriously affecting their health and even leading to death.

2. The cat will be in poor spirits and may also cause high fever.