Cordocentesis for rapid karyotyping in fetuses with congenital anomalies or severe IUGR.

The objective was to determine the role of percutaneous umbilical blood sampling (cordocentesis) as a rapid technique for chromosome analysis in a high risk obstetric population. Cordocentesis was attempted in 167 pregnant women (168 fetuses) with IUGR, a single anomaly or multiple anomalies. Gestational age ranged between 17 and 37 weeks. The procedure was successful in 152 (90%) fetuses with a blood sample withdrawan at first attempt in 80%. Neither technique was associated with any false negative or false positive findings. Postprocedural complications included one case of persistent fetal bradycardia, but no fetal death. In nine cases amniotic fluid was collected, resulting in 161 fetal blood or amniotic fluid samples for chromosome analysis. An abnormal chromosome pattern (n = 26) was established in 1/12 cases (8%) of severe IUGR, 6/88 cases (7%) with a single structural anomaly and 19/61 cases (31%) with multiple structural anomalies. In the presence of an abnormal chromosome pattern, the perinatal mortality rate was as high as 96%. There is a high association between multiple fetal anomalies and abnormal chromosome pattern.