That's something the mother should've thought of, innit?
"Can I support a child?"
I feel dirty for saying this, because it is cliché answer often used by "the other side" when I get in these sort of discussion, but "There's always adoption".
I understand what you're saying because it's the most usual thought after "oh shizzle what do I do now??" That's when sometimes instincts, morals, personal values etc can come into play and whether a baby is financially viable or not, the decision to continue with a pregnancy overrides the practical.
Even with the best of intentions, a pregnancy can happen. Similarly, the woman can be financially fine and then things can happen which are beyond her control and she can no longer afford the costs of a child - but it could be too late by then.
Adoption is a hard decision to make and not without its own stigma attached. It's why I always say there is no such thing as an easy option in unplanned pregnancy/unwanted pregnancy - unless you are one of the lucky few (and I mean few) who get no effects from being pregnant, everything is as it was before and you just get fatter, you are likely to develop some very strong feelings one way or the other during pregnancy. And with the hormone changes, you are more affected by your emotions than you would normally be and therefore not in a particularly good place to make serious decisions.
When I was pregnant by accident with Jessica, I hated it. I hated her. I hated my crap life and how everything was racing out of control. The only reason I did not abort was because I was too afraid to and figured I'd be able to reach some sort of resolve once it was time to give birth. I had her and hated her on sight. I didn't want anything to do with her but something - call it what you like - prevented me from signing on the dotted line to give her to someone else. It makes no sense, I know, but that's just how it was. I didn't love her - or even like her - until she was about 2 years old (but that's a whole 'nother story).
I remember talking about it with another mother at a centre I used to have to attend when J was small and she put it like this, "I don't want my baby but I don't want anyone else to have her either. Why? I don't know - I guess I don't want someone else to have the good stuff when I've gone through all the crap parts for no reason. I might love her one day and I don't want to regret that". I'll admit that sounds a bit off but it made perfect sense to me at the time.
Also, kids are effing expensive beggars regardless of whether you have the cash or not - I can't recall the current stats but if you looked at them, you'd never have kids at all because it seems so financially impossible unless you're a bajillionaire.