How can I talk to my friend who is trying to have a baby?

Truth is, I don't think she should have a baby. They have only been married a month and even before they were married they stopped using any kind of birth control. She says their ready for a baby. They do both work full time but their both only cashiers. They pinch enough pennies as it is. Our friendship is a little iffy because we just started talking again after not talking a couple of years. I just don't know how to tell her she shouldn't have a baby yet. She says their ready and their mature enough but I don't think so. They both want to go back to college but that isn't going to happen with a baby.