What does the term "vertex presentation" mean?

Question

Quizplus · Accepted Answer

A baby in a vertex cephalic presentation has his head down toward the cervix. This is the most common position for birth, and the least complicated. Typically the neck is flexed, and the crown of baby's head is the first part to emerge (i.e., "crowning"), but variations include face, forehead or chin vertex presentation, all of which are more painful and may require intervention during second stage. If the baby is lying sideways in the pelvis, this is called transverse lie and is typically an indication for Caesarean birth, though some babies do move into a vertex position through the force of contractions and use of productive positioning. When a baby is coming bottom-first, this is referred to as breech presentation. When the baby is facing the front of the pelvis, but is still head down, this is called an occiput posterior position.

What Does the Term "Vertex Presentation" Mean