If you are unhappy with the performance of your DH you have every right to terminate her contract and send her home, it's legal and happens frequently; it's the same the other way around: if a helper is unhappy with her employer/work condition, she can turn in her notice.
You don't need any advice; it's entirely up to you. How long has she worked for you? Do you know her well and usually like her as a person and helper? If so, cut her some slack; if not, say good-bye and get yourself another one who does her job and hopefully won't be pregnant anytime soon.