I have BUPA's top package and that still doesn't cover routine pregnancy stuff. I'm also under Pru Health through hubby's work, but again no cover for maternity stuff. We are, however, paying for a private birth - basically we get to keep our fertility consultant who will do all ante-natal appts, scans as often as we want, and he will be in charge of the labour, do the delivery and c-section if needed. He'll also see us up until 6-8 weeks after the birth. I will be in an NHS hospital, but private room. You may want to see if your hospital offers something similar (I live in Bucks). We did look at fully private, but don't want to make the journey into London and we have known our consultant for the past 18 months, so trust him.
HTH