[Fetal blood sampling for karyotype using echoguided puncture of the cord. Study of 103 pregnancies].

Subcutaneous ultrasound guided puncture of the umbilical cord was carried out in order to obtain samples of blood in 103 fetuses. This was done to get the result of the karyotype quickly, i.e. in 72 hours. The indications were for diagnosis, particularly of malformations (63 cases) or intra-uterine growth retardation (24 cases). A small proportion of the indications were those for failures to carry out amniocentesis early or for checking on mosaics that were obtained after the culture of amniotic fluid cells. In 88% of the cases it was possible to obtain a karyotype and the results were checked with the sex of the fetus and the karyotype that had been obtained from amniocentesis. There were 11 abnormalities diagnosed. The chief indication of chromosome abnormality is fetal malformation. Because the result are obtained so quickly cordocentesis should replace late amniocentesis, at present when looking for fetal abnormalities.