Percutaneous umbilical blood sampling in the management of Kell isoimmunization

As the use of Rhesus immune globulin has decreased the incidence of Rh sensitization, other red blood cell antigen systems have become relatively more common. The most common of these is the Kell antigen, which often produces unexpectedly severe fetal disease. High-resolution ultrasound was used to guide in the sampling of fetal blood directly from the umbilical cord as an aid in the management of these patients.