My wife and I excitedly expect a child this year. Her employer provides paid maternity leave. Her employer provides paid maternity leave. But she is unsure whether she will want to return to work after the child arrives. In such a life-changing situation, few of us can be absolutely certain how we'll feel six months later.
Circumstances change emotional ones as well as financial ones.
Right now she may think she'll itch for her old desk only to discover later that she yearns to have another child. Her situation is analogous to a worker out with an injury who, upon recovering his health, decides not to return to the job. Certainly, no one expects him to return his disability payments. First, she owes him an honest account of her situation so he can plan accordingly. And second, she should consider the other workers who will be affected by her actions.