Real-world evidence regarding the growth of very premature infants with small for gestational age after birth: A multi-center survey in China
Authors: Huang Xue Rong , Shen Wei , Wu Fan , Mao Jian , Liu Ling , Chang Yan-Mei , Zhang Rong , Ye Xiu-Zhen , Qiu Yin-Ping , Ma Li , Cheng Rui , Wu Hui , Chen Dong-Mei , Chen Ling , Xu Ping , Mei Hua , Wang San-Nan , Xu Fa-Lin , Ju Rong , Zheng Zhi , Lin Xin-Zhu , Tong Xiao-Mei 
Published: May 2022

Abstract
Objective: To analyze the real-world growth pattern of very premature infants (VPI) with small for gestational age (SGA) after birth by using the ΔZ value of weight at discharge and evaluate the occurrence and risk factors of extrauterine growth retardation (EUGR). Methods: The clinical data of VPI with SGA were prospectively collected from 28 hospitals in seven different regions of China from September 2019 to December 2020. They were divided into the EUGR group and the non-EUGR group according to the criterion of ΔZ value of weight at discharge < –1.28. Results: This study included 133 eligible VPI with SGA. Following the criterion for the weight at discharge as the 10th percentile of the Fenton curve, the incidence of EUGR was found to be 98.50% (131/133), and following the criterion of ΔZ value of weight at discharge < –1.28, the incidence of EUGR was 36.84% (49/133). The birth weight, the 5-minute Apgar score, and the proportion of male infants in the EUGR group were lower than those in the non-EUGR group (P < 0.05). The average invasive ventilation time, cumulative duration of the administration of antibiotics, blood transfusion time, blood transfusion ratio, and total days of hospitalization were significantly higher in the EUGR group than those in the non-EUGR group (P < 0.05). The time to start enteral feeding, the quantity of milk added with human milk fortifier (HMF), the time to reach full fortification, the cumulative fasting time, the time to reach full enteral feeding, the duration of parenteral nutrition (PN), days to reach the target total calorie intake and oral calorie intake (both 110 kcal/kg/d), and the age of recovering birth weight in the EUGR group were significantly higher than that in the non-EUGR group (P < 0.05). The average weight gain velocity (GV) was significantly lower in the EUGR group than that in the non-EUGR group (P < 0.001). The incidences of patent ductus arteriosus with hemodynamic changes (hsPDA), neonatal necrotizing enterocolitis (NEC) ³ stage 2, late-onset sepsis (LOS), and feeding intolerance (FI) in the EUGR group were significantly higher than that in the non-EUGR group (P < 0.05). Multivariate logistic regression analysis showed that birth weight, sex (male), and GV were the protective factors for EUGR, while a long time to achieve full-dose fortification, slow recovery of birth weight, and NEC ³ stage 2 were the independent risk factors. Conclusion: SGA in VPI can reflect the occurrence of EUGR more accurately by using the ΔZ value of weight at discharge than using the p-value of weight. Strengthening enteral nutrition support, achieving full breast milk fortification more earlier increasing GV, shortening the recovery time of birth weight, and avoiding NEC can effectively reduce the incidence of EUGR.