Can you provide more details on this? A cursory search doesn't turn up anything especially alarming. The only source I could find that was alarming is this[0], which I don't really trust because it reads a bit like anti-vax literature ("see what they're hiding", etc.) and is very old (all sources they cite are from 2009 or earlier). My understanding has been that the procedure has improved dramatically in that time in both cost and safety.