Hi huni, i am sorry ot hear about your friends diagnosis. Endo is a really nasty thing. It is the higher the stage the worse the endo. Stage 3 endo usually means that the endo is in several areas and there are adhesions. I have stage 3 endo and it is on the underside of my uterus, my bowel, bladder, right ovary. I had surgery 2 years ago but the docs are now reluctant to do any more surgery.
Endo can affect your chances of conceiving but that doesnt mean she wont. I had my surgery and several months later discovered i was pregnant naturally. Unfortunately i miscarried at 10 weeks but we were told we would never conceive naturally due to endo and male factor infertility. I also have a friend who has stage 4 endo and after ivf she got a positive pregnancy test and is now 20 weeks. There are plenty of success stories for people with endo getting pg either naturally or with treatment. I hope everything works out for her. xx