Prenatal Down's syndrome screening at 10-14 weeks gestation using the combined nuchal translucency and maternal serum biochemistry: preliminary results of the first 358 cases

We report our preliminary experience of prenatal screening for Down's syndrome (DS) using nuchal translucency (NT) measurement combined with the serum biochemistry analysis of Free beta-human chorionic gonadotropin (F beta hCG) and pregnancy associated plasma protein A (PAPP-A) all measurement at 10-14 weeks of gestation. Of the 358 parturient women which enrolled in the study, 9 cases were not included because of fetal anomalies or miscarriages. Thus the study group included 349 singleton pregnancies in which complete prenatal and infant follow-up was available. Forty-four pregnant women were found to be screen positive (12.6%) and in 13 cases (27%) of them fetal chromosomal aneuploidies were diagnosed. Looking into the markers profile we found that the NT was a sensitive marker which was abnormally increased in all the fetal aneuploidies. Serum F beta hCG was found to be a promising marker as well, being significantly elevated (2.26 +/- 0.86 multiple of the medians, MoM) in DS cases, and decreased (< 0.5 MoM) in two cases of Edward's syndrome. On the contrary, PAPP-A was found less sensitive, and its mean MoM values were not significantly different between DS versus euploid fetuses. Our preliminary results support the promising success of DS screening using NT and F beta hCG.