If your reasons for going back to work are only because of money then maybe think about working from home? I have heard of mums setting up their own business from home. Also there is childminding which you could do?
Personally i think it is better to stay at home with children when they are very young, but some mums want to go out to work, not just for the money, but for doing something else and meeting other people. If these are your reasons as well then maybe think about using a childminder for childcare, they are cheaper than nurseries and much better environment for little ones.