PCOS is usually the reason behind an unpredictable response to FSH. The problems really start when level sky rocket like mine. We say my FS yesterday and he's still talking about what my levels did on my stim cycle in March - it's a scary little reminder of just how bad it can get. My FS was saying that slow and steady like a plane taking off is much better than a rapid rise like a rocket taking off. Gives better egg quality, he says.

BW