Prenatal invasive procedures serve two purposes-diagnostic and therapeutic. In diagnostic tests, the aim is to identify structural or functional abnormalities of the embryo or fetus in utero. Early identification and appropriate monitoring of the abnormal embryo or fetus can palliate the severity of disease. There are many invasive prenatal diagnostic methods. This article presents information on the definitions, processes, indications and possible complications of the common invasive prenatal procedures, including amniocentesis, fetal blood sampling, chorionic villus sampling and fetal tissue biopsy.