Having enormous breast may give you back, neck and neck pain. Also may affect your posture. Also you may have difficulty running or doing some exercises that may restrain you in engaging sports.
The main health risk associated with having large breasts is ending up with serious back problems. If your frame is small and your breasts are big, your back could hurt.
Large breast implants have advantages and disadvantages. The disadvantages will help you make an informed decision about what size will be most appropriate for you in the long term.