First, do not tell the father when you go into labor and do not put his name on the birth certificate, make him prove paternity. Unless you two are married or his paternity has been established he will have
no rights to your child. He can not take your child and he can not even see your child without your permission until he has established legal paternity. Read the following post:
https://www.askmehelpdesk.com/childr...tml#post409325
You will need to go to a lawyer directly after giving birth. There is no way you will be able to do this without one. Especially if he obtains a lawyer. I would actually seek a lawyers advise prior to delivery. Call explain your situation and they will be able to tell you what will need to happen. Only a lawyer can prove he is unfit and you are fit. Only a lawyer will know what the Court will recognize in getting that done. You can get free consults from a lawyer even over the phone.
I wouldn't recommend disappearing as he can hire a private detective to hunt you down and you will have to cut all contact with your family and friends as he will be able to go through them to get to you.