There is a thread for pregnancy over 40 somewhere so you could look there.
I've been told by my SILs who work in maternity, one whom is a midwife, that it does happen but most of the women it happens to have had large families already e.g. 7+ children. (I can't remember why I asked as it was a few years back, but I think it was more to do with the birth process and articles about it being difficult for older mothers.)
If you definitely want a child your best bet is fertility treatment using donor eggs, which you have to pay for privately.