Invasive prenatal diagnosis is a series of procedures necessary to obtain fetal or embryo-fetal tissues useful for diagnosing pathologies of chromosomal and/or genetic origin. It can also be used for detecting infectious agents, metabolism errors, and/or for studying the composition of fetal fluids such as blood and urine. Most common prenatal techniques are chorionic villus sampling, amniocentesis, and cordocentesis. They are options to choose from according to the gestational age and the type of fetal pathology to investigate.