IUI with menopur

Sneha
Hi everyone, 
I'm 26 and have mild PCOS and we have been trying for 2 years and finally decided to go With IUI and last month after taking letrozole and gonal-F which didn't work as there was no development of my follicles and this month after taking letrozole and menopur injections the follicles increased to the desired size and we are going to have our 1st IUI scheduled For tomorrow, can I know the success rate with first IUI.. 
Looking for answers..