Who Is Financially Responsible For Birth Of Baby

I am six months pregnant with no maternity coverage benefits. The father and I do not and have not ever lived together and are not together now. Am I financially responsible for all current doctor visits as well as the birth of our child, or is the father responsible for half of that as well? My ob is requiring monthly payments on the delivery charges now as well as payments on the other charges, such as bloodwork and ultrasounds. He does not feel as if he is required to pay although he admits paternity and goes to all Dr visits with me. Are we both not responsible?