Supplementary Material for: Maternal and Cord Blood Adiponectin Concentrations in Small for Gestational Age: A Meta-Analysis

Background: Adiponectin, which may have a growth-promoting effect through its insulin-sensitizing action, is thought to play a key role in fetal growth. This study was performed to determine whether maternal and/or cord blood adiponectin concentrations differ between small for gestational age (SGA) and healthy controls. Methods: Databases were searched to identify good quality English language studies providing the number of SGA and healthy controls, and the means and standard deviations of maternal or cord blood adiponectin concentration in both groups. A meta-analysis was performed to summarize the standardized mean differences (SMDs) in maternal and cord blood adiponectin concentrations between SGA and healthy controls. Results: There was no statistically significant difference in maternal blood adiponectin concentration between SGA and healthy controls (n = 8, p = 0.951). However, cord blood adiponectin concentration was significantly lower in SGA than in healthy controls (n = 6, p = 0.028), and the effect was large (i.e., SMD >0.7). Conclusions: Maternal blood adiponectin concentration is not low in SGA compared with healthy controls. However, SGA shows lower cord blood adiponectin concentration than healthy controls.

**背景**：脂联素（Adiponectin）可通过其胰岛素增敏作用发挥促生长效应，被认为在胎儿生长过程中发挥关键作用。本研究旨在探究小于胎龄儿（small for gestational age, SGA）与健康对照者的母体及/或脐血脂联素浓度是否存在差异。
**方法**：我们检索了相关数据库，筛选符合高质量标准的英文研究，这些研究需提供SGA组与健康对照组的样本量，以及两组母体或脐血脂联素浓度的均值与标准差。本研究采用荟萃分析，汇总SGA组与健康对照组之间母体及脐血脂联素浓度的标准化均数差（standardized mean difference, SMD）。
**结果**：SGA组与健康对照组的母体血脂联素浓度无统计学显著差异（n=8，p=0.951）。但SGA组的脐血脂联素浓度显著低于健康对照组（n=6，p=0.028），且效应量较大（即标准化均数差>0.7）。
**结论**：与健康对照组相比，SGA患者的母体血脂联素浓度并无降低。但SGA组的脐血脂联素浓度低于健康对照组。