Advanced

By how much does increased nuchal translucency increase the risk of adverse pregnancy outcome in chromosomally normal fetuses? A study of 16 260 fetuses derived from an unselected pregnant population.

Westin, Maria-Dorothea LU ; Saltvedt, S; Almstrom, H; Grunewald, C and Valentin, Lil LU (2007) In Ultrasound in Obstetrics & Gynecology 29(2). p.150-158
Abstract
Objective: In this study we aimed to estimate the magnitude of a possible increase in risk of adverse outcome in fetuses with normal karyotype and increased nuchal translucency (NT), and to determine bow well NT measurements can distinguish between fetuses with normal and adverse outcome. Methods: We studied 16260 consecutive fetuses with normal karyotype derived from an unselected pregnant population. The following cut-offs for increased risk of adverse outcome were chosen a priori: NT >= 95(th) percentile, >= 3 mm, >= 3.5 mm, and >= 4.5 mm. The positive and negative likelihood ratios (+LR, -LR) of the risk cut-offs with regard to fetal malformation, miscarriage, perinatal death, termination of pregnancy and total adverse... (More)
Objective: In this study we aimed to estimate the magnitude of a possible increase in risk of adverse outcome in fetuses with normal karyotype and increased nuchal translucency (NT), and to determine bow well NT measurements can distinguish between fetuses with normal and adverse outcome. Methods: We studied 16260 consecutive fetuses with normal karyotype derived from an unselected pregnant population. The following cut-offs for increased risk of adverse outcome were chosen a priori: NT >= 95(th) percentile, >= 3 mm, >= 3.5 mm, and >= 4.5 mm. The positive and negative likelihood ratios (+LR, -LR) of the risk cut-offs with regard to fetal malformation, miscarriage, perinatal death, termination of pregnancy and total adverse outcome were calculated, and receiver-operating characteristics (ROC) curves were drawn. Results: The total rate of adverse outcome was 2.7%. +LR and -LR of NT >= 3.0 mm were: for lethal or severe malformation, +LR 15.0 (95% CI 7.0-28.6), -LR 0.89 (95% CI 0.81-0.9S); for malformation of at least intermediate severity, +LR 8.1 (95% CI 4.3-14.0), -LR 0.95 (95% CI 0.92-0.97); for termination of pregnancy, +LR 41.6 (95% CI 17.1-86.6), -LR 0.67 (95% CI 0.41-0.85); for any adverse outcome, +LR 6.4 (95% CI 3.4-11), -LR 0.96 (95% CI 0.94-0.98). The odds for these adverse outcomes increased with increasing NT. NT >= 3 mm did not significantly increase the risk of miscarriage or perinatal death. Areas under ROC curves for NT were small, with 95% CI below or only slightly above 0.5. Conclusion: Our likelihood ratios can be used to calculate the individual risk of unfavorable outcome, but NT screening cannot reliably distinguish between normal and adverse outcome in fetuses with normal karyotype. Copyright (c) 2007 ISUOG. Published by John Wiley & Sons, Ltd. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
screening, pregnancy outcome, nuchal translucency, malformations, miscarriage, risk assessment, ultrasound
in
Ultrasound in Obstetrics & Gynecology
volume
29
issue
2
pages
150 - 158
publisher
John Wiley & Sons
external identifiers
  • wos:000244580200007
  • scopus:33847261045
ISSN
1469-0705
DOI
10.1002/uog.3905
language
English
LU publication?
yes
id
73612c79-faf0-4985-94ba-877f422e6fa5 (old id 165080)
alternative location
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids= 17211897&dopt=Abstract
date added to LUP
2007-07-30 14:22:38
date last changed
2017-06-04 04:19:16
@article{73612c79-faf0-4985-94ba-877f422e6fa5,
  abstract     = {Objective: In this study we aimed to estimate the magnitude of a possible increase in risk of adverse outcome in fetuses with normal karyotype and increased nuchal translucency (NT), and to determine bow well NT measurements can distinguish between fetuses with normal and adverse outcome. Methods: We studied 16260 consecutive fetuses with normal karyotype derived from an unselected pregnant population. The following cut-offs for increased risk of adverse outcome were chosen a priori: NT >= 95(th) percentile, >= 3 mm, >= 3.5 mm, and >= 4.5 mm. The positive and negative likelihood ratios (+LR, -LR) of the risk cut-offs with regard to fetal malformation, miscarriage, perinatal death, termination of pregnancy and total adverse outcome were calculated, and receiver-operating characteristics (ROC) curves were drawn. Results: The total rate of adverse outcome was 2.7%. +LR and -LR of NT >= 3.0 mm were: for lethal or severe malformation, +LR 15.0 (95% CI 7.0-28.6), -LR 0.89 (95% CI 0.81-0.9S); for malformation of at least intermediate severity, +LR 8.1 (95% CI 4.3-14.0), -LR 0.95 (95% CI 0.92-0.97); for termination of pregnancy, +LR 41.6 (95% CI 17.1-86.6), -LR 0.67 (95% CI 0.41-0.85); for any adverse outcome, +LR 6.4 (95% CI 3.4-11), -LR 0.96 (95% CI 0.94-0.98). The odds for these adverse outcomes increased with increasing NT. NT >= 3 mm did not significantly increase the risk of miscarriage or perinatal death. Areas under ROC curves for NT were small, with 95% CI below or only slightly above 0.5. Conclusion: Our likelihood ratios can be used to calculate the individual risk of unfavorable outcome, but NT screening cannot reliably distinguish between normal and adverse outcome in fetuses with normal karyotype. Copyright (c) 2007 ISUOG. Published by John Wiley & Sons, Ltd.},
  author       = {Westin, Maria-Dorothea and Saltvedt, S and Almstrom, H and Grunewald, C and Valentin, Lil},
  issn         = {1469-0705},
  keyword      = {screening,pregnancy outcome,nuchal translucency,malformations,miscarriage,risk assessment,ultrasound},
  language     = {eng},
  number       = {2},
  pages        = {150--158},
  publisher    = {John Wiley & Sons},
  series       = {Ultrasound in Obstetrics & Gynecology},
  title        = {By how much does increased nuchal translucency increase the risk of adverse pregnancy outcome in chromosomally normal fetuses? A study of 16 260 fetuses derived from an unselected pregnant population.},
  url          = {http://dx.doi.org/10.1002/uog.3905},
  volume       = {29},
  year         = {2007},
}