You can pick rotations/specialties to minimise it, but even so I think you would struggle to avoid them completely. As for how long you continue doing them, it depends on your specialty. If you become a GP you might stop then, though the way things are going I think they will have to go back to doing more OOH work in the future. Most in-hospital specialties will still be doing night shifts right through training, though for some of the lab-based specialties like histopathology, or more niche ones like ophthalmology, you may be on-call from home rather than on your feet in the hospital. When you get to consultant level most on-calls are from home, though again this is changing and in certain specialties, most notably ICU and Emergency Medicine, we are moving towards a 24 hour consultant presence.