I wasn't even aware this could be a problem :( (disturbing news stories) EDIT
When I had DS I had many worries about what could go wrong but decapitation never even entered my mind. Now I have read 3 stories in the last year where this has happened. They occurred in Missouri, Kentucky, and Brazil. Now I can't help but second guess what I allowed in my own case. I didn't even know this was even a possibility. I researched a lot and learned many new things but this never even came up. How can something like this even happen?