What is the first cardinal movement of labor?

The first cardinal movement of labor is engagement. This refers to the stage where the widest part of the fetal head descends and enters the pelvic inlet, typically aligning with the ischial spines, marking the point of 0 station. Engagement is crucial as it indicates that the presenting part of the fetus has moved into the pelvic cavity, positioning it to progress through the birth canal during labor.

Understanding engagement as the initial step in the cardinal movements is important because it sets the stage for subsequent movements, which include descent, flexion, internal rotation, extension, restitution, and external rotation. These movements facilitate the effective passage of the fetus through the birth canal. Recognizing engagement as the first step offers insights into how labor progresses and what healthcare providers can expect in terms of fetal positioning and the dynamics of labor.