if clomid's worked once, will it work again?

[mumtosammy]

I conceived on my second round of clomid after TTC for 2.5 years, but sadly I miscarried. now I'm about to start on clomid again on next cycle and wondering - does the fact i responded on round 2 mean i am likely to respond again on the clomid? i have four more months to try...
anyone have experience of this happening to them? how hit and miss is clomid? thanks.