did anyone with pcos not ovulate on chlomid but ovulate on the one that start with an L ?

I went thru 4 rounds of clomid and didn't ovulate on a single one. My OBGYN told me that some ladies with pcos don't ovulate on clomid but will ovulate on the one that starts with an L (sorry don't have bottle in front of me). I just wanna know if I'm wasting my time again. I believe the medication is letrozol or something like that but I could be wrong. Just really praying I at least ovulate. 😕