Can my ex girlfriend stop me seeing my 3month old daughter when she has'nt had the courts permission and I'm on the birth certifacate?

Do you have court ordered visitation? If you do, she cannot stop you without going to jail. If you do not, she can do anything she wants.

First, please pay more attention to posting guidelines. There is a Read First sticky on the top of the Children forum (where this was moved from) that directs questions of a legal nature to this forum.

If there is a court ordered visitation schedule, then she can't legally stop you from exercising your rights under the schedule. If she tries, you go back to court and ask that she be cited for contempt.

If there is not court ordered schedule, then you have to petition the court to have one setup.

Being on the birth certificate establishes you as the legal father, but to exercise your rights as the father you have to have a court set things up.