Obstetrics and Gynecology

During the past several years, exciting and significant advances have been made in the field of antenatal diagnosis with the development of percutaneous blood sampling and chorionic villus sampling.

Percutaneous umbilical blood sampling provides direct access to fetal circulation in the second and third trimesters of pregnancy.^1,2 This technique allows a much more rapid diagnosis of chromosomal abnormalities in the second trimester: results are now possible within 72 hours as opposed to the several weeks required by traditional amniocentesis. This new technique has been useful in diagnosing fetal hematologic disorders and has proved to be helpful in the diagnosis and management of nonimmune fetal hydrops and isoimmune disorders. The fetal hemoglobin level measured directly is a much more reliable parameter for determining the necessity for intrauterine transfusions in rhesus isoimmunization than our traditional indirect parameters, such as bilirubin levels in amniotic fluid. Preliminary studies suggest that this technique might