Prenatal diagnostics has seen a rapid increase in the number of genetic disorders amenable to prenatal detection owing to advances in technology and research into the genetic etiology of many conditions. This article reviews the more traditional prenatal diagnostic techniques, such as amniocentesis and chorionic villus sampling for chromosome abnormalities and single gene disorders, and chromosome analysis of products of conception to determine the etiology of a spontaneous abortion, plus more recent advances such as rapid aneuploidy detection via fluorescence in situ hybridization and polymerase chain reaction, preimplantation genetic diagnosis, noninvasive analysis of cell-free fetal DNA in maternal circulation, and array-based comparative genomic hybridization.