It is a few years since we were at Aberdeen maternity (and there wasn't any room left in the accommodation which was very annoying as there were people from the mainland in the same ward who were using it - I don't know if it's pre-bookable nowadays?). Anyway, from what I remember (if it's any help), there is a takeaway and small shop right across the road from the hospital. We just used our own car seat for the return journey and we were responsible for fitting it ourselves in the taxi. There are regular buses to and from Union St/Bridge St - poss every 20 mins.