Prenatal diagnosis, traditionally used as a synonymous for invasive fetal testing and evaluation of chromosomal constellation, presently encompasses many other issues like pedigree analyses, fetal risk assessment, population screening, genetic counseling and fetal diagnostic testing as well. Ultrasound guided chorionic villus samling (CVS), amniocentesis and, to a lesser extent, fetal blood sampling are used routinely in fetal medicine units. Other fetal tissue biopsies such as skin, liver and muscle biopsy are used only rarely. In this chapter we discuss the invasive diagnostic procedures in maternal fetal medicine with specific interest of showing the list of indications basic principles used for choosing the particular invasive technique, linkage of non.
