I was pregnant with my first child at 17, DDs father left as soon as he found out I was pregnant and has never been involved. I was a senior in HS and raised in a very religious house so abortion was something I never even considered. It devistated my parents, and in a "tough love" move the made me move out of the house in to my own apartment (but helped with rent) and I got a job. I dropped out of my 2nd half of my senior year to get a full time job and support myself and DD. I won't lie, it was hard as hell at times. I hated my parents for it at first, and people that I tell my story to often have a very negative reaction.
The thing is, they still supported me, just not in their house. They helped watch her while I went on interviews, they came over and stayed with me at times and I still slept at their house. But it was a drastic move to make me grow up and become accountable quickly. And it worked.
I have no doubt that the right things were done (at least for me as a person) because I became a mature, self functioning, adult. I got my GED, I started attending college at night and while I had my teenage setbacks still, things were good. As a result of all of this, I am at a MUCH better place than a lot of my HS peers who partied through college, dropped out and still don't know what they are doing with their lives.
So honestly, I don't have much advice besides support her how you feel its best, and love her unconditionally. But I wanted to share my story to provide a positive turn out to what is often a really hard situation.