Amniocentesis and chorionic villus sampling.

Amniocentesis and chorionic villus sampling have been shown through prospective, multicenter trials to be safe and effective methods of prenatal diagnosis; accordingly, a knowledge of these tests is important for those physicians who care for women during their childbearing years. We review the indications, techniques, safety, accuracy, and efficacy of amniocentesis and chorionic villus sampling and compare the advantages and disadvantages of each diagnostic test. This review should enable physicians to provide appropriate counseling and information to women at increased risk for fetal abnormalities detectable by either of these procedures.