I'm so sorry for your loss! I had a somewhat late loss (although not as late as yours), and it was so very painful. I can only imagine at 23 weeks. :( I think there are a lot of things that can cause losses. If there were several genetic abnormalities that showed on testing, it's possible that there were other genetic abnormalities for which they didn't test that caused the problem. Cord accidents can cause this, placental abnormalities or abruption...did they offer you any sort of post-miscarriage testing?