I am an nHS mw specialising in homebirth. We recently had a 6th baby at home (which was fine). Statistically there is an increased risk once you get past 5 but that doesn't mean you have to deliver in hospital. The risks of PPH with high parity also have a relation to your age and general health. In this situation we would discuss the risk ie the background stats, how quickly paramedics can arrive in your area, transfer time to hospital, your personal history of labour, delivery, bleeding and avoiding anaemia. Ultimately its your decision and we would make a plan to reduce the risk. The Supervisor of midwives offers support and advice to both mothers and mws, and this is usually reassuring. You might want to talk to her, she might offer to see you at home (with your big family responsibilities).
We would offer to put a cannula in a vein in order to give emergency drugs if they were needed but if you are very fast, there might not be time before delivery! We also carry a drug called misoprostil which can be given after delivery to control bleeding, if the usual drugs, syntocinon, ergometrine are not enough.
Another concern is that when you have had a lot of babies, the womb gets very stretchy and sometimes this allows the baby to take up odd positions, making them difficult to deliver eg transverse, lying crossways.
The other annoying thing that can happen with a womb that has had a lot of babies is that the contractions might be uncoordinated, ie painful but not progressing the labour. This can happen in women who have previously delivered swiftly. Its not dangerous in itself but medical aid might be needed to get delivered.