Thank you so much girls for all your responses..Posting here and getting some answers from all of you has helped me lot in coping in this hard times..
I am so sorry for your loss. I just wanted to let you know it is completely normal to miscarry naturally and not have a dnc. I miscarried at 14 weeks and my boy and placental tissue came away. In regards with pcos I do not know much about it except that it can make falling pregnant and pregnancy difficult.
I agree with the last message that you should call the hospital and ask them to do some tests. They did tests on my baby and it came back inconclusive or rather unexplained because they couldn't find any abnormalities. That really destroyed me because I started thinking it was all my fault but eventually I had to think it was nature's way as cruel as it might be. I would ask them to do some testing just n case
I don't know anything about pcos, but in answer to question 1, it's perfectly safe to have a natural miscarriage without following it up with a D&C if you know that all the tissue was passed. The doctor can tell that by doing two blood tests for hCG, 48 hours apart, or doing one test and getting a "0" level on it. She can also often tell by looking with an ultrasound.
And as far question 2, it means that anything which was in your uterus has left it, and you have an empty uterus now.
I would ask a doctor or a specialist in polycystic ovarian disease the question about whether it can cause a miscarriage (there might have been some other cause -- did they test the fetus?) since I always thought the problem with polycystic ovarian disease was getting pregnant, not keeping a pregnancy. And ask that same specialist question 4.
I don't want to sound cold-blooded, but if no tests were done on the fetus, and if you miscarried at the hospital, they might still have the remains in the lab, and could do some testing to see what caused the miscarriage. I learned when I miscarried in a hospital setting that they hold the embryo for a month, in case there are questions. It would help to know that testing was done, so you can put to rest that assertion that polycystic ovarian disease caused the miscarriage.