Thanks to everyone who's posted. I'm a bit scared now! 
While it's possible for me to come back to the UK to have the baby (and, given we are currently living overseas, I could go private
), DH and I decided it would be best for me to have the baby out here, as otherwise it would mean us spending several weeks apart, both in very late pregnancy and also in the early weeks after delivery before it's safe to fly home. Also there is the risk of him missing the birth if the baby comes early...
I have said to myself that if I develop major complications later on, that I'd definitely just come home, but if it looks like a 'normal' delivery, it's best to be here, at home, as it's just simplest all round.
However, am a bit alarmed by what everyone's saying now. I think this has given me food for thought - I will check with more women who've given birth here, enquire about doulas and also ask at next week's ante-natal class for the midwife to really clarify hospital policy on episiotomies and enemas, asking about what clinical research they base their interventions on.
Thanks for everyone's replies - it's been so helpful to hear from those with medical knowledge and also people who have had enemas etc, and that they weren't the end of the world. I suppose as long as one has the right to refuse, that would be ok.
But the option of saying no to an episiotomy, which would presumably happen at the most painful and chaotic part of labour, seems more limited. I know one woman here who specifically asked not to be cut, but her doctor cut her anyway. Of course, there may have been a medical reason, but the doctor just dived straight in there and cut her
. There was no medical emergency - it was a straightforward birth - but maybe the doc felt she would tear
.