I've done a bit of research into this area when we were formulating our maternity leave policy. You are entitled not to work for the first 12 months (regardless of whether or not you had paid maternity leave). So in theory you could stop working for a few more months...

In most cases, when you except paid maternity leave you are in turn agreeing to return to work for the company for a period of time (usually 12 months), but you do not have to return for the first 12 months. Most companies have the right to ask you to pay the money back if you don't honor the arrangement.

Hope this helps...