What is a common complication of untreated gestational diabetes?

Macrosomia, which refers to an excessive birth weight, is a common complication of untreated gestational diabetes. When a mother has elevated blood sugar levels during pregnancy, the excess glucose can pass through the placenta to the fetus, leading to increased insulin production in the baby. This high insulin level promotes fat deposition and growth, resulting in macrosomia.

A newborn with macrosomia is more likely to have complications during delivery, including shoulder dystocia, which is a situation where the baby's shoulder gets stuck during birth. Additionally, cesarean delivery is more common in cases of macrosomia due to the increased size of the baby, which can complicate the vaginal delivery process.

In contrast to macrosomia, low birth weight is typically associated with undernutrition or other complications, not gestational diabetes. Neonatal hypoglycemia can occur after birth in infants of mothers with uncontrolled diabetes, but it is not as directly associated with the condition as macrosomia. Preterm labor can have many causes and is not a direct complication of gestational diabetes in the same way that macrosomia is. Thus, macrosomia is the most straightforward and well-known complication resulting from untreated gestational diabetes.