Invasive prenatal diagnostic procedures 2005

Amniocentesis and Chorionic Villus Sampling have been the two most common prenatal diagnostic procedures for decades. There are wide variations in utilization, operator skills, quoted procedure risks, actual observed risks, and patient choices that come from highly variable counseling as to those risks. The compilation of published data suggests procedure risks of amniocentesis to be about 1/200 and in very skilled hands to be slightly lower. The risks of CVS in very experienced hands may also be about 1/200. Most studies comparing CVS to amniocentesis in skilled hands have found equivalency of risks. No well controlled studies support claims of amniocentesis risk at 1/1000 or lower. There is no increased risks of limb reduction defects followng CVS at 10 weeks or greater, but there is an increase in Talipes from "Early Amniocentesis." In the first trimester CVS is the safer procedure.