Investigation of the association between maternal serum ferritin levels and preterm delivery: A systematic review and meta-analyses

Elevated levels of maternal serum ferritin, especially during the second trimester, are linked to PTD. However, the adjusted OR estimates have not shown statistical significance. There is considerable variability among the studies and a risk of bias that warrants cautious interpretation. Additionally, the diagnostic thresholds reported differ greatly and lack sufficient validation for clinical application. It is essential to conduct standardized prospective studies before ferritin-based clinical decision-making can be endorsed.