Significance of Sonological Evaluation of Nuchal Translucency and Correlation with Pregnancy Outcome
M Raksha, KVN Dhananjaya, KV Malini, Aparna Baliga
Chromosomal anomalies, First trimester, Nuchal translucency, Prospective study
Citation Information :
Raksha M, Dhananjaya K, Malini K, Baliga A. Significance of Sonological Evaluation of Nuchal Translucency and Correlation with Pregnancy Outcome. J South Asian Feder Obs Gynae 2019; 11 (4):225-229.
Aims and objectives: To determine the effectiveness of the first-trimester nuchal translucency (NT) scan and prospective study with pregnancy outcome. (1) The study involves prenatal sonological evaluation of NT between 11 weeks and 13 weeks 6 days of gestation. (2) To correlate NT and congenital anomalies. Materials and methods: Study design: This study was performed on pregnant women with gestational age of 11 weeks and 13 weeks 6 days at Kasturba Medical College and Govt. Lady Goschen Hospital, Mangaluru, from March 2, 2009 to March 10, 2011. Pregnant women undergone screening are followed up till delivery and assessment of congenital anomalies done. Inclusion criteria: (1) Pregnant women with gestational age of 11 weeks and 13 weeks 6 days. (2) Crown-rump length between 45 mm and 84 mm. Subjects: Subjects are screened with ultrasonography and data entered. The subjects are followed up till the pregnancy outcome. The clinical assessment of the newborn baby was done to look for any congenital anomalies. The statistical analysis was done by using the Chi-square test. p < 0.05 is considered to be significant. Techniques: (1) NT measurements done in the sagittal view of the fetus in the neutral position. (2) Magnification was such that only upper two-thirds of fetus were included in images. (3) Maximal subcutaneous translucency overlying neck was measured. (4) Measurement was taken with the horizontal lines placed on the lines that define the nuchal translucency thickness. Results: (1) Increase in NT is associated with congenital abnormalities. (2) Increased NT is 551.41 times likely to have anomalies compared with normal NT. Conclusion: Nuchal translucency is a strong predictor of congenital and chromosomal anomalies.
Adams MM, Erickson JD, Layde PM, et al. Down's syndrome: recent trends in the United States. JAMA 1981;246(7):758–760. DOI: 10.1001/jama.1981.03320070042022.
Wald NJ, Kennard A, Hackshaw AK, et al. Antenatal screening for Down syndrome. J Med Screen 1997;4:181–246. DOI: 10.1177/096914139700400402.
Bromley B, Leibermann E, Shipp TD, et al. The genetic sonogram, a method for risk assessment for Down syndrome in the midtrimester. J Ultrasound Med 2002;21(21):1087–1096. DOI: 10.7863/jum.2002.21.10.1087.
Bromley B, Leibermann E, Shipp TD. Foetal nose bone length: a marker for Down syndrome in the second trimester. J Ultrasound Med 2002;21(12):1387–1394. DOI: 10.7863/jum.2002.21.12.1387.
Nicolaides KH, Snijders RJM, Gosden CM, et al. Ultrasonographically detectable markers of foetal chromosomal abnormalities. Lancet 1992;340(8821):704–705. DOI: 10.1016/0140-6736(92)92240-G.
Wald NJ, Densem JW, George L, et al. Prenatal screening for Down syndrome. Prenat Diagn 1996;16:143–153. DOI: 10.1002/(SICI)1097-0223(199602)16:2<143::AID-PD825>3.0.CO;2-F.
Nicolaides KH. The 11-13+6 weeks scan. London: Foetal Medicine Foundation; 2004. pp. 15–17.
Nicolaides KH, Snijders RJM. Features of chromosomal defects. Diagnosis of foetal abnormalities—The 18-23 weeks scan. London; 2002. pp. 99–101.
Souka AP, Krampl E, Bakalis S, et al. Outcome of pregnancy in chromosomally normal foetuses with increased nuchal translucency in the first trimester. Ultrasound Obstet Gynecol 2001;18(1):9–17. DOI: 10.1046/j.1469-0705.2001.00454.x.
Brigatti KW, Malone FD. First trimester screening for Aneuploidy. Obstet Gynecol Clin N Am 2004;31(1):6–7. DOI: 10.1016/S0889-8545(03)00119-0.
Scott F, Boogert A, Sinosich M, et al. Establishment and application of a normal range for nuchal translucency across the first trimester. Prenat Diagn 1996;16(7):629–634. DOI: 10.1002/(SICI)1097-0223(199607)16:7<629::AID-PD922>3.0.CO;2-X.
Snijders RJM, Nobel P, Sebire N, et al. UK multicentre project on assessment of risk of trisomy 21 by maternal age and foetal nuchal translucency thickness at 10-14 weeks of gestation. Lancet 1998;351(9125):343–346. DOI: 10.1016/S0140-6736(97) 11280-6.
Souka AP, Snijders RJM, Novakov A, et al. Defects and syndromes in chromosomally normal foetuses with increased nuchal translucency at 10-14 weeks of gestation. Ultrasound Obstet gynecol 1998;11(6):391–400. DOI: 10.1046/j.1469-0705.1998.11060391.x.
Vintzileos AM, Ananth CV, Smulian JC, et al. Cost benefit analysis of prenatal diagnosis for Down syndrome using the British or the American approach. Obstet Gynecol 2000;95:577–583. DOI: 10.1016/S0029-7844(99)00613-4.
Nicolaides KH, Azar G, Byrne D, et al. Foetal NT: Ultrasound screening for chromosomal defects in the first trimester of pregnancy. BMJ 1992;304:867–869. DOI: 10.1136/bmj.304.6831.867.
Pandya PP, Kondylios L, Hilbert L, et al. Chromosomal defects and outcome in 1015 foetuses with increased NT. Ultrasound Obstet Gynecol 1995;5(1):15–19. DOI: 10.1046/j.1469-0705.1995.05010015.x.
Wayda K, Keresztúri A, Orvos H, et al. Four years experience of first-trimester nuchal translucency screening for foetal aneuploidies with increasing regional availability. Acta Obstet Gynecol Scand 2001;80(12):1104–1109.
Bethune M. Literature review and suggested protocol for managing ultrasound soft markers for Down syndrome: thickened nuchal fold, echogenic bowel, shortened femur, shortened humerus, pyelectasis and absent or hypoplastic nasal bone. Australiasian Radiol 2007;51(3):218–225. DOI: 10.1111/j.1440-1673.2007.01713.x.
Bromley B, Lieberman E, Shipp TD, et al. The genetic sonogram: a method of risk assessment for Down syndrome in the 2nd trimester. J Ultrasound Med 2002;21(10):1087–1096. DOI: 10.7863/jum.2002.21.10.1087.
Pajkrt E, De Graff IM, Mol BWJ, et al. Weekly nuchal translucency measurements in normal foetuses. Obstet Gynecol 1998;91:208–211. DOI: 10.1016/S0029-7844(97)00658-3.
Wald NJ, Hackshaw AK, Huttly W. Screening for Down's syndrome: Serum screening programmes are effective and safe. BMJ 2000;321:763–764.
Cuckle H. Screening for Down syndrome: Statistical modelling is the best tool for formulating screening policy [letter]. BMJ 2000;321: 763.
Nicolaides KH. The 11-13+6 weeks scan. London: Foetal medicine foundation; 2004. pp. 24–25.
Sonek J. First trimester ultrasonography in screening and detection of foetal anomalies. Am J Med Genet Part C Semin Med Genet 2007;145C(1):45–61. DOI: 10.1002/ajmg.c.30120.
Hyett JA, Perdu M, Sharland GK, et al. Increased nuchal translucency at 10-14 weeks of gestation as a marker for major cardiac defects. Ultrasound Obstet Gynecol 1997;10(4):242–246. DOI: 10.1046/j.1469-0705.1997.10040242.x.
Ogle RF, Chitty LS. Prenatal screening for Down syndrome. Hospital Medicine 1998;59(8):632–636.
Nicolaides KH, Snijders RJM. Features of chromosomal defects. Diagnosis of foetal abnormalities - the 18-23 weeks scan. London; 2002. pp. 100–102.
Morris JK, Wald NJ, Watt HC. Foetal loss in Down syndrome pregnancies. Prenat Diagn 1999;19(2):142–145. DOI: 10.1002/(SICI)1097-0223(199902)19:2<142::AID-PD486>3.0.CO;2-7.
Down LJ, Observations on an ethnic classification of idiots. Clin Lectures and Reports, London Hospital. 1866;3:259–262.
Kypros H. Nicolaides, The 11 –13+6 weeks scan. London: Foetal Medicine Foundation; 2004. p. 21.