ABSTRACT
INTRODUCTION Fetal blood sampling was initially performed at hysterotomy.1 e subsequent development of fetoscopy in the 1960s allowed fetal vessel puncture under direct visualization. However, fetoscopy was cumbersome and risky since the procedure-related loss rates exceeded 5%. e development of high-resolution ultrasound made it possible to clearly image the umbilical cord. Spurred by a desire to accurately diagnose fetal toxoplasmosis, Daos performed the rst intentional percutaneous umbilical blood sampling under ultrasound guidance (cordocentesis) in the early 1980s.2 e procedure rapidly gained favor with demonstration of its safety3-5 and directly spurred the development of fetal medicine. If necessary for technical reasons, fetal blood can also be obtained under sonographic guidance from either the fetal heart (cardiocentesis) or the intrahepatic umbilical vein (hepatocentesis).6 A wide range of gestational appropriate fetal norms (hematological, endocrinological, immunological, biochemical, and biophysical)7 were developed, a crucial step in the evolution of fetal medicine. While many early indications for cordocentesis have been supplanted by less invasive techniques, there remain several indications for fetal blood sampling. e most common are the assessment and treatment of red cell and platelet alloimmunization, the rapid antenatal diagnosis of inherited blood or metabolic diseases, rapid karyotyping of malformed or severely growth-restricted fetuses in some countries, and rarely the determination of fetal acid base status.8
