International Journal of Infertility & Fetal Medicine

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VOLUME 2 , ISSUE 2 ( May-August, 2011 ) > List of Articles

RESEARCH ARTICLE

The 11-13+6 Weeks Scan: Where do We Stand? A 5-year Review at Fernandez Hospital

Suseela Vavilala, K Geeta

Citation Information : Vavilala S, Geeta K. The 11-13+6 Weeks Scan: Where do We Stand? A 5-year Review at Fernandez Hospital. Int J Infertil Fetal Med 2011; 2 (2):65-69.

DOI: 10.5005/jp-journals-10016-1020

License: CC BY-NC 4.0

Published Online: 01-08-2011

Copyright Statement:  Copyright © 2011; The Author(s).


Abstract

Objective

To examine the clinical utility of 11-13+6 weeks scan for screening for chromosomal abnormalities and to assess the potential value of the same ultrasound examination in the early diagnosis of fetal structural anomalies.

Design

A prospective interventional study at Fetal Medicine Unit, Fernandez Hospital Pvt Ltd, a tertiary care perinatal center, Hyderabad, India, between September 2005 and March 2010.

Methods

All pregnant women < 13+6 weeks at booking are offered a routine obstetric scan between 11 and 13+6 weeks. All scans are done by obstetricians who are accredited by Fetal Medicine Foundation. All expectant mothers undergoing 11-13+6 weeks scan were included; all expectant mothers with antenatal booking after 14 weeks were excluded from the study.

Results

Between September 2005 and March 2010, a total of 11,012 scans were done between 11 and 13+6 weeks. Complete follow-up was available for 7,916 cases; 1,460 are ongoing pregnancies and 1,636 expectant mothers were lost to follow-up. The median maternal age in our population is 27 years and 340 (4.30%) mothers had advanced (> 35 years) maternal age. The median NT in our population is 1.58 mm. Increased nuchal translucency (NT > 95th percentile) was found in 362 (4.59%) scans. Miscarriages/abortions and termination of pregnancy were significantly higher in women whose fetus had an increased nuchal translucency thickness. Nuchal translucency thickness was significantly higher in women with advanced maternal age (ANOVA F = 0.002, Fishers exact test p-value for equality of medians = 0.04). Absent fetal nasal bones were present in 20 (5.57%) of women with increased NT compared to five (0.07%) women with normal NT. Among 7,916 women, 367 (4.64%) women were screen positive for chromosomal abnormalities. After counseling, only 40 screen-positive women accepted prenatal diagnostic procedures. Skull/brain abnormalities were found in 25 fetal images, abdominal abnormalities in 17, spinal abnormalities in eight, bladder abnormalities in five and cardiac abnormalities in five fetal images.

Conclusion

The 11-13+6 weeks ultrasound scan is an important diagnostic tool that should be offered to all pregnant women as a routine standard of antenatal care in the first trimester of pregnancy in India. However, as a screening tool, it mandates addition of cost-effective biochemical tests. To make the combined screening cost-effective, this study calls for making a national policy for Down's syndrome screening for India.


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  1. Some thoughts on the true value of ultrasound. Ultrasound Obstet Gynecol 2007;30(5):671-74.
  2. Learning curve in ultrasonography screening for selected fetal structural anomalies in early pregnancy. Obstet Gynecol 2003;101: 273-76.
  3. A close look at early embryonic development with the high-frequency transvaginal transducer. Am J Obstet Gynecol 1988;159:676-81.
  4. The measurement of nuchal translucency with transvaginal and transabdominal sonography– success rates, repeatability and levels of agreement. Br J Radiol 1995;68:720-23.
  5. Qualified and trained sonographers in the US can perform early fetal anatomy scans between 11 and 14 weeks. Am J Obstet Gynecol 2004;191:1247-52.
  6. First trimester pregnancy scanning as a screening tool for high risk and abnormal pregnancies in a district general hospital setting. Obstet Gynecol 2002;22:159-65.
  7. Assessment of fetal anatomy at 12 to 13 weeks of gestation by transabdominal and transvaginal sonography. Br J Obstet Gynaecol 1996;103: 82-85.
  8. The 11-13+6 weeks scan. http://www.fetalmedicine.com/fmf/FMF-English.pdf.
  9. The optimal gestational age to examine fetal anatomy and measure nuchal translucency in the first trimester. Ultrasound Obstet Gynecol 1998;11: 258-61.
  10. Assessment of fetal anatomy at 11-14 weeks ultrasound examination. Ultrasound Obstet Gynecol 2004;24: 730-34.
  11. Ultrasound screening of fetal structural abnormalities at 12-14 weeks in Hong Kong. Prenat Diagn 2004;24:92-97.
  12. The value of sonography in early pregnancy for the detection of fetal abnormalities in an unselected population. Br J Obstet Gynaecol 1999;106:929-36.
  13. Fetal transabdominal anatomy scanning using standard views at 11 to 14 weeks’ gestation. Am J Obstet Gynecol 2005;192:535-42.
  14. Screening for major structural abnormalities at the 11 to 14 week ultrasound scan. Am J Obstet Gynecol 2006;194:393-96.
  15. First trimester ultrasonographic diagnosis of structural abnormalities in a low-risk population. Br J Obstet Gynaecol 1998;105:53-57.
  16. Screening for fetal anomalies by ultrasound at 14 and 21 weeks. Ultrasound Obstet Gynecol 1997;10:375-80.
  17. Transvaginal ultrasonographic detection of congenital anomalies in the first trimester. Am J Obstet Gynecol 1990;163:466-76.
  18. 13-14 weeks fetal anomaly scan: A 5-year prospective study. Ultrasound Obstet Gynecol 2010;35: 292-96.
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