SO problems

My fiancé constantly goes out to see his friends at like midnight and stays out until 3am or later when I'm pregnant. It stresses me out because I can't sleep if he's not sleeping with me. We're having a baby. He can't do that once it's born. That's not okay. He needs to be there to take care of it too. He can't just leave me home so he can have fun with his friends. I've already confronted him about it and he doesn't care. What do I do?