Study on the relationship between the levels of irisin in umbilical cord blood and neonatal growth in China

Abstract

Objective: The results of the study on the relationship between obesity and cord blood irisin were far apart. The aim of this study was to explore the relationship between cord blood irisin levels and neonatal growth in China.Methods: A cross-sectional study of 400 neonates and their mothers was conducted in the obstetrics department of Shandong provincial hospital in China. Neonates were divided into a fetal macrosomia group and a normal birth weight group based on customized birth-weight standards and divided into non-high-ponderal index group and high ponderal index group based on ponderal index. Levels of irisin in umbilical cord blood were measured by enzyme-linked immunosorbent assay.Results: Irisin concentrations in the fetal macrosomia group were significantly higher than in the normal birth weight group (p = .032). Irisin levels in the high ponderal index group were significantly higher compared with the non-high-ponderal index group (p = .032). After adjustment for confounding variables, logistic regression analysis identified macrosomia affected factors include weight gained during pregnancy (OR = 1.15, p = .028), infant's sex (OR = 9.73, p = .001) and found that affected factors of high ponderal index include weight gained during pregnancy (OR = 1.08, p = .025), maternal age (OR = 1.10, p = .018). Compared with the reference category (<108.62 ng/ml), infants with a cord blood irisin level above 241.44 ng/ml had significantly elevated risk of macrosomia (OR = 8.57, p = .010) and had significantly elevated risk of high birth ponderal index (PI) (OR = 3.15, p = .002). A nonlinear relationship was observed between irisin levels and fetal macrosomia. The higher the concentration of irisin, the greater the risk of fetal macrosomia.Conclusions: We found that as the cord blood irisin increased, the risk of having fetal macrosomia was greater. Weight gained during pregnancy and high cord blood irisin levels were independent predictors of fetal adiposity.

Keywords: Birth weight; cord blood irisin; macrosomia; ponderal index; weight gained during pregnancy.