I suffered an incomplete miscarriage at 12 weeks that was extremely painful, in fact it hurt more than naturally delivering my 9 lb full term baby. But I also suffered a missed
miscarriage at 11 weeks that showed no
symptoms at all. No pain, no cramping, no bleeding, nothing.
Many women, especially in early miscarriages, will pass the blood and tissue with minimal or no pain. It can be a very different experience depending on a whole bunch of different factors.