age alone is, unfortunately, not on your side. that in itself reduces your chances of success with any assisted conception technique.

i would be thinking that, any time you commit to trying naturally, you're reducing your chances of success as you're using up viable eggs without success. if you've been trying for more than six months, and have not had success, and don't have an obvious reason you're not pregnant (ie you're not ovulating) i would think moving into IVF is probably a good move. YES, it's invasive, YES it's expensive, and YES, there is no guarantee of success - but you're more likely to get pregnant by IVF if you start earlier rather than later. the longer you leave it, the more your chances of success will dwindle...