Neuropediatrics 2004; 35(6): 321-324
DOI: 10.1055/s-2004-830365
Original Article

Georg Thieme Verlag KG Stuttgart · New York

Fetal Cells in Maternal Blood: A Six-Fold Increase in Women who have Undergone Amniocentesis and Carry a Fetus with Down Syndrome: A Multicenter Study

E. Falcidia1 [*] , E. Parano2 [*] , A. Grillo3 , P. Pavone4 , H. Takabayashi5 , R. R. Trifiletti6 , P. Scollo7 , B. Dallapiccola8 , P. Grammatico8 , A. Novelli9 , D. Paladini10 , G. Monni11 , A. Gulisano12 , G. Scassellati13
  • 1Fertilia, Human Reproduction Medicine Unit, Catania, Italy
  • 2Institute of Neurological Science, The National Research Council of Italy, CNR, Catania, Italy
  • 3Labogen, Human Genetic Laboratory, Catania, Italy
  • 4Department of Pediatrics, University of Catania, Italy
  • 5Division of Human Genetics, Medical Research Institute, Kanazawa Medical University, Ishikawa, Japan
  • 6Department of Neurology and Neuroscience, UMDNJ, Newark, NJ, USA
  • 7Department of Obstetrics and Gynecology, Cannizzaro Hospital, Catania, Italy
  • 8Department of Experimental Medicine and Pathology, Medical Genetics, University La Sapienza, and IRCCS - CSS San Giovanni Rotondo and CSS Mendel, Rome, Italy
  • 9IRCCS - CSS San Giovanni Rotondo and CSS Mendel, Rome, Italy
  • 10Prenatal Diagnosis Unit, Department of Obstetrics and Gynecology, University Federico II, Naples, Italy
  • 11Microcitemic Hospital, Prenatal Diagnosis Unit, Cagliari, Italy
  • 12Department of Obstetrics and Gynecology, University of Catania, Italy
  • 13Obstetrics and Gynecology Unit, San Camillo-Forlanini Hospital, Rome, Italy
Further Information

Publication History

Received: January 14, 2004

Accepted after Revision: September 12, 2004

Publication Date:
15 November 2004 (eFirst)


Fetal nucleated red blood cells (FNRBCs) circulate in the maternal blood throughout pregnancy. Even if the frequency of fetal cells in the maternal circulation remains to be ascertained, complications of pregnancy such as fetal cells aneuploidies, preeclampsia, abnormal Doppler of the uterine artery without symptoms of preeclampsia, fetal growth restriction and polyhydramnios are associated with an increased feto-maternal trafficking. Based on these observations, previous studies have suggested that determination of the fetal nucleated red blood cell count (FNRBCC) might be a useful non-invasive screening test, either alone or in combination with existing maternal tests, for the non-invasive assessment of aneuploidies, in particular Down syndrome (DS). In this paper we have evaluated the distribution of FNRBCC in a set of 18 normal pregnancies and 18 pregnancies with a trisomy 21-affected fetus, matching for gestational age, maternal age, and, when possible, fetal gender, in order to quantify the difference in the number of fetal cells between the two populations. Maternal blood was collected from each pregnant woman two to three weeks after amniocentesis after knowing the cytogenetic results. Correlation of FNRBCC with the gestational week and clinical status (affected vs. non affected) by multiple regression analysis provided significant results (p < 0.001). Adjusted values of FNRBCC were 48 ± 10.2 in controls and 301 ± 17.01 in DS cases, corresponding to a 6.27fold increase. These retrospective results prompt a prospective evaluation of the use of FNRBCC for screening purposes.


1 These authors contributed equally to the manuscript.

MD Enrico Parano

Institute of Neurological Science
The National Research Council of Italy - CNR

Viale Regina Margherita 6

95123 Catania