Which maneuver relieves shoulder dystocia in a macrosomic infant?

• A. Woods screw maneuver
• B. McRoberts maneuver
• C. Suprapubic pressure
• D. Zavanelli procedure

Answer: (B)

When a macrosomic baby’s shoulder becomes stuck after the head is delivered, the first and fastest maneuver to relieve the impaction is to reposition the mother's pelvis by flexing the hips sharply toward the abdomen (the McRoberts maneuver). This position changes the angle and width of the birth canal, increasing the space in the pelvic inlet and reducing the obstruction at the level of the pubic symphysis. With the pelvis realigned, the anterior shoulder has a better chance to slip under the pubic arch and be delivered.

This approach is quick, requires no equipment, and can be performed immediately as the team provides assistance. It’s often used in combination with gentle suprapubic pressure to encourage the anterior shoulder to move downward and forward. Other techniques, like internal rotation of the shoulder (Woods screw) or more invasive steps such as the Zavanelli procedure, are reserved for when initial maneuvers fail.