What may result in impaired blood flow to a newborn?

Impaired blood flow to a newborn can occur due to a prolapsed umbilical cord. In this scenario, the cord slips ahead of the presenting part of the fetus during delivery, which can compress the cord and restrict blood flow and oxygen supply to the baby. This situation can lead to severe complications, including fetal distress or hypoxia, as the cord is essential for delivering oxygen-rich blood from the placenta to the fetus.

Breech delivery, while it can lead to other complications, typically does not directly impair blood flow in the same manner. Normal delivery usually supports healthy circulation, and excessive maternal movement generally does not cause a significant risk to blood flow as long as there are no other complicating factors. Therefore, the presence of a prolapsed umbilical cord is a critical concern that directly links to impaired blood circulation, marking it as the correct answer in this context.