The 2 things id look at are cage mates and diet.

If she is being housed with a male they can get a bit aggressive while being "amorous".

Highest liklihood is that you are feeding too much protein. You really dont want it to be above 24% ... preferrably it would be around 18% for a nursing female, and around 14% for males and non-nursing females.

If you are feeding a cat food or a grocery store dogfood then you are most likely exceeding their protein needs.

Bryan