Nguyen Hai Long1, Tran Danh Cuong2, Ngo Toan Anh3, Le Pham Sy Cuong3, Nguyen Thi Thu Huong3, Phan Thi Tinh3, Nguyen Duy Linh1, Nguyen Xuan Viet1, Chu Quang Dao1, Vu Huy Hoang1
1 Hai Phong Obstetrics and Gynecology Hospital
2 Hanoi Medical University
3 National Hospital of Obstetrics and Gynecology

Main Article Content


Objectives: Determination of the prevalence of all chromosomal defects and its distribution in fetuses with increased nuchal translucency thickness. Methodology: This is a retrospective study among pregnant women indicated for amniocentesis by nuchal translucency above 2.5 mm and consent to the study. 2720 cases were included to the study during 6 years’ period from 2015 to 2020. All singleton pregnancies whose nuchal transluciency measurements were equal or over 2.5mm, were indicated for amniocentesis. Results: The study was consist of 2720 amniocentesis in which fetal nuchal transluciency was elevated. The median maternal age was 29.19 years old (range 17-46), and the median fetal crown-rump length was 66.9 mm (range 45– 84). The fetal karyotype was abnormal in 560 (20.6%) pregnancies. The popular chromosomal conditions were including trisomy 21(55%), trisomy 18 (11.2%), trisomy 13 (3.9%), 45, XO (2.7%). Chromosomal aberrations rate was 17.6% at maternal age of 30- 34, 34% and 50.0% at maternal age of 35- 39 and ≥ 40 respectively. Conclusion: In fetuses with increased nuchal translucency, more than a half of the chromosomal aberrations were trisomy 21 (55.0%). Structural rearrangements were 22.5%. Advanced maternal age (above 35) increases the risk of chromosomal aberrations.

Article Details


[1] Carles EEP, Cytogenetique prenatal: Bilan 1999 pour L’Association des Cytogenetique de Langue Francaise (ACLF), Medecine Foetale et Echographie en Gynecologie, 2002; 6(50): 5-8.
[2] Steele MW, Breg WR, Chromosome analysis of human amniotic-fluid cells, Lancet, 1966; 1(7434): 383-5.
[3] Kim MH, Park SH, Cho HJ et al., Threshold of nuchal translucency for the detection of chromosomal aberration: comparison of different cut-offs, Journal of Korean medical science, 2006; 21(1): 11-14.
[4] Valenti C, Schutta EJ, Kehaty T, Prenatal diagnosis of Down's syndrome, Lancet, 1968; 2(7561): 220.
[5] Yang YH, Ju KS, Kim SB et al., The Korean collaborative study on 11,000 prenatal genetic amniocentesis, Yonsei Med J, 1999; 40(5): 460-6.
[6] Han SH, An JW, Jeong GY et al., Clinical and cytogenetic findings on 31,615 mid-trimester amniocenteses, Korean J Lab Med., 2008; 28(5): 378-85.
[7] Chang YW, Chang CM, Sung PL et al., An overview of a 30-year experience with amniocentesis in a single tertiary medical center in Taiwan, Taiwanese journal of obstetrics & gynecology, 2012; 51(2): 206-211.
[8] Nicolaides KH, Nuchal translucency and other first-trimester sonographic markers of chromosomal abnormalities, Am J Obstet Gynecol, 2004; 191(1): 45-67.
[9] Snijders RJ, Noble P, Sebire N et al., UK multicentre project on assessment of risk of trisomy 21 by maternal age and fetal nuchal-translucency thickness at 10-14 weeks of gestation. Fetal Medicine Foundation First Trimester Screening Group, Lancet, 1998; 352(9125): 343-6.
[10] Souka AP, Snijders RJ, Novakov A et al. , Defects and syndromes in chromosomally normal fetuses with increased nuchal translucency thickness at 10-14 weeks of gestation, Ultrasound Obstet Gynecol, 1998; 11(6): 391-400.
[11] Has R, Kalelioglu I, Ermis H et al., Screening for fetal chromosomal abnormalities with nuchal translucency measurement in the first trimester, Fetal Diagn Ther., 2006; 21(4): 355.
[12] Kollmann M, Haeusler M, Haas J et al. , Procedure-related complications after genetic amniocentesis and chorionic villus sampling, Ultraschall Med., 2013; 34(4), 345-8.
[13] Ocak Z, Özlü T, Yazıcıoğlu HF et al., Clinical and cytogenetic results of a large series of amniocentesis cases from Turkey: report of 6124 cases, J Obstet Gynaecol Res., 2014; 40(1): 139-46.
[14] Hook EB, Cross PK, Schreinemachers DM, Chromosomal abnormality rates at amniocentesis and in live-born infants, Jama, 1983; 249(15): 2034-8.
[15] Wellesley D, Dolk H, Boyd PA et al., Rare chromosome abnormalities, prevalence and prenatal diagnosis rates from population-based congenital anomaly registers in Europe, Eur J Hum Genet, 2012; 20(5): 521-6.