I get 12 months paid maternity leave in my job (3 months on full salary and 9 months on 60% salary).

A condition of this is that I have to come back to work for a minimum of 6 months full time or equivalent part time.

If I don't return to work the company can have the salary I received while on leave repaid.

But I think this is because there is a fair bit of money involved in my arrangement - if it were only one month of pay I don't think they'd sweat it. You'd need to check with your employment because as paid maternity leave doesn't have to be provided by law, companies make their own rules.