What Is The Treatment For PCOS And Brownish Discharge?

I am 30 years, trying to get pregnant but i have severe PCOS..I was on BC pills. On day 15 missed a pill and after 2-3 days started dark brown bleeding..When to the doctor for a scan and was told that my endometrium has become really thick. I was advised to take Primolut N on the 2nd day of heavy bleeding (2 tabs/day) for 2 weeks and then start BC pills on the 3rd day of next period and continue for 3 months. I was also advised to go for IVF with ovarian drilling. Even though I had a laproscopy done but without ovarian drilling. I need to know why the enometrium has thickened so much and what are my chances to get pregnant?