Related Experiment Video
Updated: Aug 20, 2026
Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts
Published on: January 29, 2018
Unadjusted and customised weight centiles in the identification of growth restriction among stillborn infants
Vivian Lyon1, Allan Howatson, Khalid S Khan
1Department of Obstetrics, Princess Royal Maternity Hospital, Glasgow, Scotland, UK.
Insights
Customized weight standards do not improve the identification of intrauterine growth restriction (IUGR) in stillborn infants compared to unadjusted standards. Both methods equally identified severe IUGR but failed to detect moderate cases.
Area of Science:
- Perinatal Pathology
- Fetal Growth Assessment
- Neonatal Autopsy
Background:
- Intrauterine growth restriction (IUGR) is a significant concern in perinatal mortality.
- Accurate identification of IUGR is crucial for understanding stillbirth etiology.
- Standardized methods for assessing fetal growth are essential in postmortem examinations.
Purpose of the Study:
- To compare the effectiveness of unadjusted versus customized birthweight standards in identifying IUGR in unexplained stillborn infants.
- To evaluate the utility of customized standards in accounting for physiological variables.
- To determine if customized standards offer improved diagnostic accuracy over unadjusted standards.
Main Methods:
- Postmortem examination of 51 unexplained stillborn infants.
- Calculation of unadjusted birthweight centiles using ultrasonically derived fetal weight standards.
- Calculation of customized birthweight centiles using an online calculator adjusting for physiological variables.
- Assessment of IUGR based on brain/liver weight ratios (>3 for moderate, >5 for severe).
Main Results:
- Neither unadjusted nor customized standards identified stillborn infants with moderate IUGR (brain/liver ratio > 3).
- Both standards equally identified severe IUGR (brain/liver ratio > 5) with high sensitivity (95%) but low specificity (63% and 66%).
- Customizing weight standards did not enhance the identification of growth-restricted stillborn infants.
Conclusions:
- Customized birthweight standards offer no significant advantage over unadjusted standards for identifying IUGR in unexplained stillborn infants.
- Current standards, whether adjusted or unadjusted, have limitations in detecting all grades of IUGR in stillborn populations.
- Further research may be needed to develop more accurate methods for diagnosing IUGR in perinatal autopsies.
Abstract:
The study aims to compare the utility of unadjusted with customised weight standards in the identification of intrauterine growth restriction (IUGR) among unexplained stillborn infants undergoing postmortem examination. Unadjusted and customised birthweight centiles were determined for 51 unexplained stillborn infants undergoing perinatal autopsy. Unadjusted centiles were calculated from an ultrasonically derived fetal weight standard. Customised centiles were calculated from an online calculator which adjusts the standard to account for important physiological variables. IUGR was defined as moderate or severe according to brain/liver ratios of > 3 and > 5, respectively. The relationship between the weight centiles and abnormal brain/liver weight ratios was explored. Neither unadjusted nor customised standards identify stillborn infants with brain/liver ratios > 3:1. Both unadjusted and customised weight standards identify stillborn infants with brain/liver ratios > 5 equally well with high sensitivity (95%) but low specificities (63% and 66%, respectively). Customising weight standards to account for physiological variables does not identify growth restricted stillborn infants more usefully than an unadjusted fetal weight standard.
Related Concept Videos
01:17z Scores and Area Under the Curve
01:52Regression Toward the Mean