Current knowledge
In mothers with GDM, the higher levels of blood glucose pass through the placenta into the fetal circulation. From the second trimester onwards, the fetal pancreas responds to the hyperglycemia by secreting insulin, resulting in hyperinsulinemia. This combination of hyperinsulinemia and hyperglycemia leads to an increase in the fat and protein stores of the fetus, resulting in macrosomia. Many studies have explored the impact of GDM and fetal macrosomia and shown the effects on maternal and fetal health.