We ttc for 18 months before our natural BFP, but DH was the one with the issues. I had 'severe' endo on the vagina and bowel and was told it has a lot to do with where it is i.e. the fallopian tubes and ovaries are likely to make it harder to ttc whereas where I had it isn't likely to affect your chances of ttc at all. My lap (and follow up lap) were about 6 years before we fell pregnant.
Has your DH been checked? And have you had tests to make sure you're Oing etc?