Amniocentesis and chorionic villus sampling.

Invasive prenatal diagnosis continues to be the gold standard for pregnancies at increased risk of chromosomal aneuploidy or other genetic disease. Chorionic villus sampling is the procedure of choice for the first trimester. Early amniocentesis has been shown to carry increased risks of pregnancy loss, amniotic fluid leakage and talipes equinovarus. Mid-trimester amniocentesis continues to be the most common form of invasive prenatal diagnosis, with post-procedural loss rates of between 0.5 and 1%. This present review summarizes information on technique risks, looks at new technology applied to invasive prenatal diagnosis testing, and reports on new diagnoses that could be made either by amniocentesis or chorionic villus sampling.