Validation of a model for optimal birth weight: a prospective study using serial ultrasounds

BMC Pediatrics

David Lawrence²  Eve Blair²  Gavin Pereira¹ 

[1] Yale School of Public Health, Center for Perinatal, Pediatric and Environmental Epidemiology, Yale University, New Haven, CT, 06510, USA;Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, 100 Roberts Road, Subiaco, WA, 6008, Australia

关键词: Proportion of optimal birth weight;    Preterm delivery;    Fetal growth;   

Others  :  1170771
DOI  :  10.1186/1471-2431-12-73

 received in 2011-04-06, accepted in 2012-06-04,  发布年份 2012

【 摘 要 】

Background

The aim of this study was to validate a model for optimal birth weight derived from neonatal records, and to test the assumption that preterm births may be considered optimally grown if they are not exposed to common factors that perturb fetal growth.

Methods

Weights of fetuses were estimated from serial biometric ultrasound scans (N = 2,848) and combined with neonatal weights for a prospective pregnancy cohort (N = 691). Non-Caucasians, fetuses subsequently born preterm and those with diagnosed or suspected determinants of aberrant growth were excluded leaving fetuses assumed to have experienced normal growth. A generalised linear longitudinal growth model for optimal weight was derived, including terms for gestational duration, infant sex, maternal height and birth order. This model was compared to a published model derived solely from birth weights.

Results

Prior to 30 weeks gestation, the published model yielded systematically lower weights than the model derived from both fetal weight and neonatal weight. From 30 weeks gestation the two models were indistinguishable.

Conclusion

The model for optimal birth weight was valid for births that have attained at least 30 weeks gestation. The model derived from both fetal and neonatal weights is recommended prior to this gestation.

【 授权许可】

   
2012 Pereira et al.; licensee BioMed Central Ltd.

【 图 表 】

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