A 26-year-old primigravida develops gestational diabetes and remains hyperglycemic during the remainder of her pregnancy. Which of the following abnormalities in the newborn child is likely related to the maternal hyperglycemia?
**Core Concept**
Gestational diabetes mellitus (GDM) is characterized by insulin resistance and impaired insulin secretion, leading to hyperglycemia in pregnant women. Maternal hyperglycemia can affect fetal development, particularly in the second and third trimesters.
**Why the Correct Answer is Right**
The correct answer is related to the fetal macrosomia, which is a common complication of maternal hyperglycemia. Fetal macrosomia occurs due to the excessive glucose crossing the placenta, stimulating insulin production in the fetus. This leads to an increase in fetal growth, particularly in muscle and fat, resulting in a larger than average birth weight. The fetal pancreas becomes hyperplastic and hypertrophic, producing excess insulin, which promotes growth and development.
**Why Each Wrong Option is Incorrect**
**Option A:** Hypoglycemia in the newborn is not directly related to maternal hyperglycemia, as the fetus produces excess insulin to counteract the maternal glucose levels.
**Option B:** Congenital anomalies are not directly related to maternal hyperglycemia, as they are caused by genetic or environmental factors during fetal development.
**Option C:** Respiratory distress syndrome (RDS) is not directly related to maternal hyperglycemia, as it is caused by a deficiency of surfactant in the lungs.
**Clinical Pearl / High-Yield Fact**
Fetal macrosomia is a significant risk factor for birth trauma, including brachial plexus injury, shoulder dystocia, and cesarean delivery.
**Correct Answer:** C. Fetal macrosomia