knocking a chick up, hypothetical situation

[xxThe_Lebowskixx]

You have a one night stand with a girl you barely know and the condom breaks. She promises that she is going to take a morning after pill. You leave it at that and don't see or think about her for another eight months until she gets back in touch with you and says that she needs to know your name and details for the hospital papers because she is having your baby!

What is your course of action? What responsibility do you have towards the child?