Associations Between the Features of Gross Placental Morphology and Birthweight

• Authors: Alexa A. Freedman, Emory University; Carol Hogue, Emory University; Carmen Marsit, Emory University; Augustine Rajakumar, Emory University; Alicia Smith, Emory University; Robert L. Goldenberg, Columbia University; Donald J. Dudley, University of Virginia; George R. Saade, University of Texas Medical Branch; Robert M. Silver, University of Utah; Karen J. Gibbins, University of Utah; Barbara Stoll, Emory University; Radek Bukowski, University of Texas Austin; Carolyn Drews-Botsch, Emory University
• Journal Title: Pediatric and Developmental Pathology
• Volume: Volume 22, Number 3
• Publisher: SAGE Publications Inc. | 2019-05-01, Pages 194-204
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1177/1093526618789310
• Subjects: Health Sciences, Pathology; Health Sciences, Human Development; Health Sciences, Obstetrics and Gynecology; Health Sciences, Epidemiology
• Keywords: Science & Technology; Life Sciences & Biomedicine; Pathology; Pediatrics; placental size; placental shape; birthweight; placenta; neonatal; fetal; Growth; Shape; Size; Term; Singleton; Surface

Abstract

The placenta plays a critical role in regulating fetal growth. Recent studies suggest that there may be sex-specific differences in placental development. The purpose of our study was to evaluate the associations between birthweight and placental morphology in models adjusted for covariates and to assess sex-specific differences in these associations. We analyzed data from the Stillbirth Collaborative Research Network's population-based case–control study conducted between 2006 and 2008, which recruited cases of stillbirth and population-based controls in 5 states. Our analysis was restricted to singleton live births with a placental examination (n = 1229). Characteristics of placental morphology evaluated include thickness, surface area, difference in diameters, shape, and umbilical cord insertion site. We used linear regression to model birthweight as a function of placental morphology and covariates. Surface area had the greatest association with birthweight; a reduction in surface area of 83 cm2, which reflects the interquartile range, is associated with a 260.2-g reduction in birthweight (95% confidence interval, −299.9 to −220.6), after adjustment for other features of placental morphology and covariates. Reduced placental thickness was also associated with lower birthweight. These associations did not differ between males and females. Our results suggest that reduced placental thickness and surface area are independently associated with lower birthweight and that these relationships are not related to sex.