Prenatal Genetic Counseling in Congenital Anomalies

Abstract

The impact of genetic variability on embryogenesis and fetus development established medi- cal genetics as essential for the prevention of congenital anomalies, early detection and appro- priate management. Advances in ultrasonography equipment and technique allow early detection of many congenital malformations. In addition, genetic testing can be performed in a prenatal setuing on a variety of biological samples obtained by invasive and noninvasive procedures: chorionic villus sampling, amniocentesis, cordocentesis, or maternal blood collec- tion (i.e., cell free fetal DNA). In the past, only a small percentage of congenital anomalies had a readily identifjable etiology; genetic diagnostic procedures can provide at least some of the answers for the remaining unsolved cases. Undoubtedly, the need for appropriate case man- agement and counseling justifjes the importance of uncovering the underlying genetic cause of birth defects. In this chapter, we will focus on genetic counseling in congenital anomalies, including isolated congenital anomalies and preimplantation genetic diagnosis. Genetic coun- seling provides information and support, assisting parents in making informed decisions. Through this process, parents learn about the risk of having a newborn with a congenital malformation and the nature of the disorder and its natural history, are advised on available testing for that particular case, and discuss options for risk management and family planning.