Gestational diabetes (GD) is a condition that affects some pregnant women and can have adverse effects on the fetus and the mother. One of the organs that may be affected by GD is the umbilical cord (UC), which connects the fetus to the placenta and provides oxygen and nutrients. This review aims to summarize the current evidence on the histopathological, biochemical and functional changes in the UC and its vessels in GD pregnancies, and their implications for fetal and neonatal outcomes