At the end of the day, it has to be her decision whether she keeps the baby or not. You can talk to her about it and tell her why it might not be a good idea, but she needs to make the decision herself. if she wants to keep it, respect the fact she is giving up her future really, to care for the baby. At least she's taking responsibility for having sex at her age by giving the baby a chance at life. Has she thought about having the baby and putting it up for adoption? That might not appeal to her as an option, but she could think about it.
Having the baby is going to turn her life upside down. She'll have to miss school for a while, if not stop going unless someone can look after the baby for her. there are some schools you can take your baby to though. She'll have to support herself in the next few years, find a job and a house, which will be hard if she and the dad aren't together.
She should talk to the dad about it too. Taking his opinion on abortion into account, and find out if he'd pay for some of the baby's costs (he should have to) if she has the baby.
If she decides to abort, it's not a decision to be taken lightly. She might feel incredibly guilty afterwards and regret it. Although, it would enable her to carry on with a 'normal life'
Hope I helped a bit :) if you want to talk you can PM me, good luck to her x
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you're no oil painting.