It gives you a higher chance of getting pregnant and a higher chance of twins. Both have to be fertilized though and that doesn't happen often. Many ladies get 2-3 mature follicles
on clomid and still don't concieve (conceive). I did double ovulate one month according to the DR but still didn't get pregnant. I did get pregnant later on though with IUI.
I would say a higher chance of getting pregnant. Focus on that. Twins sound great but there are a lot of complications. If you are doing IUI then a few good follicles