A Case Of Shoulder Dystocia (Obstertrics)

A 25-year-old G2P1 woman is delivering at 42 weeks’ gestation. She is moderately obese, but the fetal weight clinically appears to be about 3700 g. After a 4-hour first stage of labor, and a 2-hour second stage of labor, the fetal head delivers but  is noted to be retracted back toward the patient’s introitus. The fetal shoulders do not deliver, even with maternal pushing.

1. What is your next step in management?
2. What is a likely complication that can occur because of this situation?
3. What maternal condition would most likely put the patient at risk for this condition?

Answers And Discussion:


1. What is your next step in management?
Answer: McRoberts maneuver (hyperflexion of the maternal hips onto the maternal abdomen and/or suprapubic pressure).

2. What is a likely complication that can occur because of this situation?
Answer:  A likely maternal complication is postpartum hemorrhage; a common neonatal complication is a brachial plexus injury such as an Erb palsy.

3. What maternal condition would most likely put the patient at risk for this condition? 
Answer: Gestational diabetes, which increases the fetal weight on the shoulders and abdomen.

Shoulder Dystocia: Inability of the fetal shoulders to deliver spontaneously, usually due to the impaction of the anterior shoulder behind the maternal symphysis pubis.

McROBERTS MANEUVER: The maternal thighs are sharply flexed against the maternal abdomen to straighten the sacrum relative to the lumbar spine and rotate the symphysis pubis anteriorly toward the maternal head.
SUPRAPUBIC PRESSURE: The operator’s hand is used to push on the suprapubic region in a downward or lateral direction in an effort to push the fetal shoulder into an oblique plane and from behind the symphysis pubis.

Clinical Approach:
Because of the unpredictability and urgency of shoulder dystocia, the clinician should rehearse its management and be ready when the situation is encountered.

Shoulder dystocia should be suspected with

• fetal macrosomia, 
• maternal obesity,
• prolonged second stage of labor, and 
• gestational diabetes. 

Significant fetal hypoxia may occur with undue delay from the delivery of the head to the body. Moreover, excessive traction on the fetal head may lead to a brachial plexus injury to the baby. It should be recognized that brachial plexus injury can occur with vaginal delivery not associated with shoulder dystocia, or even with cesarean delivery.
Shoulder dystocia is not resolved with more traction, but by maneuvers to relieve the impaction of the anterior shoulder.
The diagnosis is made when external rotation of the fetal head is difficult, and the fetal head may retract back toward the maternal introitus, the “turtle sign.”
The first actions are nonmanipulative of the fetus, such as the McRoberts maneuver and suprapubic pressure. Fundal pressure should be avoided when shoulder dystocia is diagnosed because of the increased associated neonatal injury. Other maneuvers include the Wood’s corkscrew (progressively rotating the posterior shoulder in 180° in a corkscrew fashion), delivery of the posterior arm, and the Zavanelli maneuver (cephalic replacement with immediate cesarean section).
One area of controversy is the practice of cesarean delivery in certain circumstances in an attempt to avoid shoulder dystocia; indications include macrosomia diagnosed on ultrasound, particularly with maternal gestational diabetes. Because of the imprecision of estimated fetal weights and prediction of shoulder dystocia, there is no uniform agreement regarding this practice. Operative vaginal delivery, such as vacuum or forceps-assisted deliveries in the face of possible fetal macrosomia, may
possibly increase the risk of shoulder dystocia.