I am on maternity leave and have heard on the grapevine that the person who was covering me while I was away is being made permanent. Should I be worried?

The impact of maternity leave on women's careers has been in the headlines lately. In theory you are very well protected by law during pregnancy and maternity leave and have the right to return to work at the end of it either to the same job (if you return within six months) or one that is suitable for you and no less senior and well paid (if you return after a longer absence).