What do you do if female rabbit keeps letting her babys die?

It is a common thing for an animal not to care for their babies when they are young and not used to having litters. It's almost like they don't realize that they are supposed to feed, nurture and raise them. I have seen cases where a cat will try to eat her kittens, thinking they are prey. I haven't seen a rabbit do that before, but just to give you some insight. Some rabbits may get used to having babies and eventually learn to care for them. However, my best advice is to either get her spayed, or keep her away from the male that she is breeding with. There is no reason to contribute more to the over population of animals, or allow the mother to kill more of her babies.