What is the expected physiological change in insulin levels after birth?

After birth, insulin levels in the newborn typically decrease due to the closure of the umbilical cord. Before birth, the fetus relies on maternal glucose and insulin levels for regulation of its own glucose metabolism. When the umbilical cord is cut, the direct supply of maternal insulin, which helps maintain fetal blood glucose levels, is interrupted. As a result, the newborn's pancreas experiences a shift in its insulin production in response to the sudden change in blood glucose levels and the absence of maternal influence.

This decrease in insulin is important for the newborn as the body begins to adapt to ex utero life, where it must independently regulate its own blood glucose levels without the maternal supply. The newborn's physiological response helps to prevent hypoglycemia that can occur as the maternal glucose is no longer available.

While feeding might indeed increase insulin levels in the newborn later on, this response does not happen immediately after birth. Therefore, the physiological decrease in insulin levels right after delivery through umbilical cord closure is a key adaptive change that facilitates the adjustment of the infant's metabolism to life outside the womb.