תוצאת חיפוש

Prenatal Down's Syndrome Screening at 10-14 Weeks Gestation using the Combined Nuchal Translucency and Maternal Serum Biochemistry: Preliminary Results

Ron Maymon^1*, Marina Bergman², Shmuel Segal²,  Eli Dreazen¹, Zwi Weinraub¹ and Arie Herman¹

¹Department of Obstetrics and Gynecology, Assaf Harofe Medical Center, Zerifin 70300 (affiliated with Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv), Israel. ²Department of Obstetrics and Gynecology, Barzilai Medical Center, Ashkelon (affiliated with Ben Gurion University, Be'er-Sheeba), Israel.

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 b-human chorionic gonadotropin (FbhCG) 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 FbhCG 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 FbhCG.

Screening for Down's Syndrome by Measuring Fetal Nuchal Translucency Thickness

Ron Maymon, Eli Dreazen, Zwi Weinraub, Ian Bukovsky, Arie Herman

Ultrasound Unit, Dept. of Obstetrics and Gynecology, Assaf Harofeh Medical Center, Zerifin, and Sackler Faculty of Medicine, Tel Aviv University

Increased fetal muchal translucency (NT) thickness at 10-14 weeks of gestation may indicate underlying fetal chromosomal abnormalities, anatomical anomalies and genetic syndromes. Between January 1997 and May 1998, 1400 women 10-14 weeks pregnant underwent sonographic screening for detection of Down's syndrome (DS). Follow-up was complete in 1208 (86%).

Maternal age ranged from 17-44 years (mean 18.0). 87% were found by screening to have a higher risk (1:380) for DS diagnosed at birth. All these fetuses were karyotyped and 8 had chromosomal abnormalities. 2 fetuses with normal NT were diagnosed later as having DS, 1 by the mid-gestation triple test and 1 by amniocentesis because of advanced maternal age.

Thus sonographic screening identified 8 out of 10 fetuses found to have chromosomal abnormalities at birth. Neonates not karyotyped before birth had no traits at birth that justified chromosomal analysis. Results of this study suggest that NT measurement, combined with maternal age, is an effective 1st trimester screening method for DS in an unselected obstetric population.

Outcome in Fetuses with Increased Nuchal Translucency Thickness

Ron Maymon, Eli Dreazen, Yosi Tovbin, Zwi Weinraub, Arie Herman

Ultrasound Unit, Dept. of Obstetrics and Gynecology, Assaf Harofeh Medical Center, Zerifin and Sackler Faculty of Medicine, Tel Aviv University

Increased thickness of fetal nuchal translucency (TNT) measured at 10-14 weeks of gestation, may suggest underlying fetal chromosomal defects, structural abnormalities or genetic syndromes. We examined the relationship between increased TNT and pregnancy outcome, especially in fetuses with normal karyotypes.

1400 pregnant women underwent first trimester scanning and screening for chromosomal abnormalities and measurement of fetal TNT. 25 fetuses (2%) with increased TNT (>3 mm) were identified. 8 (30%) had an abnormal karyotype. Of these, 5 pregnancies were aborted, 3 ended in spontaneous abortions before karyotyping, and 2 were terminated, all before detailed cardiac scanning. There was a high association between increased TNT and karyotype abnormalities. The total incidence of favorable outcome in fetuses with normal chromosomal and cardiac features but enlarged TNT was 56%.

Trisomy 18 Anomalies on Sonography and Calculated Risk of Chromosomal Abnormalities During First Trimester

Ron Maymon, Arie Herman, Eli Dreazen, Mati Glasner, Zvi Weinraub

Ultrasound Unit, Dept. of Obstetrics and Gynecology, Assaf Harofeh Medical Center, Zrifin, and Sackler School of Medicine, Tel Aviv University; and Women's Health Center, Kupat Holim, Holon Branch, Tel Aviv-Jaffa District

Trisomy 18 is a chromosomal disorder giving multiple anomalies. Its frequency depends on maternal age. We report a 28-year-old woman in her first pregnancy, who underwent first trimester scanning for screening. Due to increased nuchal translucency and exomphalos, chorionic villous sampling was performed. Cytogenetic diagnosis was trisomy 18 and termination of pregnancy was carried out immediately.