Hey,
moving out and in with your boyfriend is a huge step and a big test of your love for each other in the first place. Bringing a baby along would be even harder. Maybe you could try moving first to see how stable it is, and if it's an environment you would want to raise a child in. Either way, I believe you should wait, but at least then you'd know. There are so many other things to do at 15 then raise a child. Once you have a baby, nothing is about you anymore, it's all about your son or daughter.Your young and you deserve to experience the world without the overwhelming responsibility of a child. A new baby can come between it's parents and take up most of their time together, and can strain any relationship if not done properly. Don't get me wrong, babies are amazing and having one is like nothing else in this world, but think about how much better the whole experience could be if your stable, married, and finished with school so you can really enjoy your child without the added stress of finishing school and struggling to make ends meet (babies are expensive!)
Another thing, if your boyfreind is that close to being 18, your parents can press charges for statatory rape if they feel the need, becuase your still a minor. Imagine being pregnant with his baby while he's in jail! I'm a soon to be single mom, due in three weeks, and I can tell you that going to every appointment alone and setting up and moving baby furniture alone and just being alone in general at a time in life that should be cheerful and celebratory is really tough and lonely. I'm sure delivering alone will be no fun either. I know your in love, but i know that ending up alone happens becuase it happened to me. Whatever you decide, just know that this decision, once you decide to have a child, isn't one that can be undone. you can't change your mind, or go back to your old life. Having a baby really does change everything! good luck!