Cordocentesis as a method of fetal blood sampling was first carried out in the 1960s under fetoscopic guidance and carried a procedure-related fetal loss rate of over 5%. The first percutaneous umbilical cord sampling under ultrasound control was reported by Daffos et al. In 1983 this development revolutionized the technique, allowing access to the fetal vascular compartment for both diagnostic and therapeutic means, with a procedure-related fetal loss rate of less than 2%. The major complications of cordocentesis are fetal bradycardia, bleeding at the puncture site or occasionally asystole. The world experience of cordocentesis is much smaller than for other invasive techniques such as chorionic villous sampling (CVS) or amniocentesis.