Funding sources: None
Sonographic fetal weight estimation – is there more to it than just fetal measurements?
Article first published online: 17 NOV 2013
© 2013 John Wiley & Sons, Ltd.
Volume 34, Issue 1, pages 50–55, January 2014
How to Cite
Barel, O., Maymon, R., Vaknin, Z., Tovbin, J. and Smorgick, N. (2014), Sonographic fetal weight estimation – is there more to it than just fetal measurements?. Prenat. Diagn., 34: 50–55. doi: 10.1002/pd.4250
Conflicts of interest: None declared
- Issue published online: 2 JAN 2014
- Article first published online: 17 NOV 2013
- Accepted manuscript online: 4 OCT 2013 11:23AM EST
- Manuscript Accepted: 29 SEP 2013
- Manuscript Revised: 10 SEP 2013
- Manuscript Received: 9 JUL 2013
The primary aim of this study was to evaluate the effects of different maternal, fetal, and examiner related factors on the accuracy of sonographic fetal weight estimation (SFWE).
A retrospective cohort study analyzing 9064 SFWEs performed within 1 week prior to delivery, including singleton pregnancies with a gestational age of 37 to 42 weeks, was recorded at one medical center from January 2004 to September 2011. Predicted birth weights were calculated according to models by Sabbagha et al., Hadlock et al., and Combs et al. and were compared with the actual birth weight. Effects of different factors on SFWE accuracy were assessed. The systematic error, random error, and mean absolute percentage error were used as measures of accuracy.
High maternal weight, height, body mass index, multiparity, older maternal age, diabetes, and fetal male sex were associated with underestimation of SFWE (P < 0.05). Fetal presentation and the sonographer's experience influenced SFWE differently using various models. The amniotic fluid index did have a significant effect on SFWE. Overall, more than 90% of the systematic errors were unaccounted for in the factors we assessed.
Many maternal and fetal factors significantly influence the SFWE; nevertheless, most errors are probably due to inherent problems in SFWE formulas. © 2013 John Wiley & Sons, Ltd.