What is the first cardinal movement of labor?

• A. Flexion
• B. Descent
• C. Internal rotation
• D. Extension

Answer: (B)

Descent is the first cardinal movement of labor. It describes the downward passage of the presenting part (usually the fetal head) through the maternal pelvis as contractions push it lower. This initial movement sets the stage for the remaining movements—flexion (tucking the chin toward the chest), internal rotation (aligning with the pelvis), extension (the head extends under the pubic arch), and then external rotation and expulsion. Without descent, the head wouldn’t reach the pelvic floor to begin the sequence of rotations and extensions. Factors like pelvic anatomy, fetal position, and the strength of contractions influence how effectively descent occurs.