My son is three months old. He goes to bed late at night and sleeps on…

My son is three months old. He goes to bed late at night and sleeps on my chest. We usually go to bed around 7:30 PM. He eats, falls asleep with his mouth open on my breast and may sleep until 10:00 PM. When I take his breast away he seeks me out again and asks for it. When do babies stop sleeping on their mother's breasts? What should I do in general?