Effects of Gestational Diabetes Mellitus on Fetal Liver Length: A Systematic Review and Meta-Analysis

Gestational diabetes mellitus (GDM) is a serious pregnancy complication that can affect various organs and organ systems of the mother and fetus. In diabetic mothers, increased blood glucose delivery to the fetus leads to fetal hyperglycemia and hyperinsulinemia, which promotes the growth of insulin-dependent organs such as the liver. Therefore, this systematic review and meta-analysis was conducted to more precisely estimate the association between GDM and fetal liver length (FLL).

Six electronic databases (PubMed, Scopus, Web of Science, ProQuest, Cochrane, and Wiley) were searched up to Aug 2023. Two reviewers independently extracted data and assessed the risk of bias using the Newcastle-Ottawa Scale. The pooled weighted and standardized mean differences in FLL were calculated using random-effects models. Heterogeneity, subgroup analysis, and publication bias were also assessed using funnel plots. All statistical analyses were performed using Stata Version 16.0.

Twelve articles were included in the final meta-analysis. GDM was associated with increased FLL, as assessed by ultrasound, in both the second (SMD=1.56; 95% CI: 1.04, 2.08; P<0.001) and third (SMD=0.84; 95% CI: 0.07, 1.61; P<0.001) trimesters of pregnancy. The pooled mean difference in FLL between the GDM and non-GDM groups was 4.85 mm (WMD=4.85; 95% CI: 3.26, 6.45), indicating larger liver size in fetuses from mothers with GDM.

GDM is a significant risk factor for increased FLL, as assessed by ultrasound, which may reflect fetal overgrowth and metabolic dysfunction.