It depends on a few important things. First, AKC now refers to the breed as just a Boston Terrier, and have dropped the "Bull." As you may already know, many Bostons have trouble delivering their pups and are often delivered by c-section. The answer lies in the size of each dog. It's important to know about the dog you plan to breed her with. How big are his sire and dam? How big were/are his siblings? Pit bulls can be very large, and if your Boston is not considered "large" by definition, she will likely need to be delivered at your vet by C-section. If you can't breed her to a similar or smaller Boston (or smaller breed dog) you may be taking on more than you want to deal with. The breeding of the 2 may make delightful pets, but my sister has a pit/boxer with the most gentle nature in the world, but if he's caught off guard or scared, look out!