Huh. NC for this, but apparently people like me don't exist, so perhaps I shouldn't have bothered.
I was pregnant at 15, had my baby when I had just turned 16.
Went back to (grammar) school, did A Levels.
Went to RG university, got my degree.
Got a job, got a car, rented a house, sent DC to school, got married.
Bought my first house aged 26. I'm still in my 20s now.
I'm not earning shed loads of money, my job is of the vocational "work your way up" variety, but if all goes to plan I'll be professional level within the next few years. If not, well, I love what I do and it pays the bills.
I would have been a rubbish business owning multimillionaire, but I can't say that was ever the plan 
My DC is doing extremely well. Very academic child, top of class etc,plenty of friends etc.
My parents are both professionals who were working full time when I got pregnant. They were devestated of course, but they were supportive. They didn't raise my baby though, I did. I basically flexi-schooled.
It was absolutely not their fault I got pregnant, or a reflection on their parenting. I was an intelligent but socially hopeless teen, who unfortunately crossed the path of a very nasty, though outwardly charming, middle class "naice" boy. He has nothing to do with my child but has gone on to make plenty of other people miserable as an adult man.
Would I recommend having a baby as a teenager? No I wouldn't. Do I think it's the end of the world if it does happen? No I don't. It bloody well seemed to be when I was 15, but now as an adult, I'm very happy and so is my family, and as an adult I'm doing all the things you'd expect.
Honestly, it all feels so long ago. I think that's what I am rather clumsily trying to say. Teenage motherhood does have an expiry date. At some point, the girl becomes a woman. I don't believe on defining grown women solely by their role as mother, and I think it's worth bearing that in mind with girls too.
Sorry I'm not an Oxbridge don though - what a disappointment. Lorna Sage managed something similar, though I can't recall if it was Oxbridge or somewhere else.