prenatal diagnosis

prenatal diagnosis Diagnosis before birth. Methods for prenatal diagnosis include ultrasound of the uterus, placenta, and/or developing fetus; chorionic villus sampling (CVS) to obtain tissue for chromosome or biochemical analysis; and amniocentesis to obtain amniotic fluid for the analysis of chromosomes, enzymes, or DNA. A growing number of birth defects and diseases can be diagnosed prenatally and in some cases treated before birth. Also known as antenatal diagnosis.