Shoulder dystocia is an obstetrical complication that occurs in approximately 30,000 deliveries in the US every year. In this medical emergency, the child’s head is able to clear the cervix, but the shoulders become impacted behind the mother’s pelvis. This impaction may prevent a vaginal delivery. In such cases, the baby’s face will exhibit what is known as a turtle sign, where the head appears to be pulled back tightly against the vulva. This is generally the first sign that there is a problem. The fear is that if the shoulder is not quickly dislodged, the baby is not able to breathe because the vaginal canal is compressing against the baby’s chest. Additional maneuvers are then required to properly deliver the baby.
When this occurs, most physicians initially perform a variety of conservative procedures to free the baby’s shoulders. These procedures are part of the standard of care in deliveries where shoulder dystocia occurs, and may include:
· the McRobert’s maneuver, where the mother’s thighs are hyperflexed to widen the pelvic outlet
· Gaskin maneuver where the mother is placed into an all fours position on her hands and knees. This may not be possible in cases involving epidural anesthesia.
· Rubin I, where suprapubic pressure is applied to the mother’s pubic bone, to rotate and dislodge the shoulder under the pubis symphysis.
· Rubin II, where posterior pressure is placed on the anterior shoulder
· Woods maneuver, where the physician inserts a hand to rotate the fetus either way to facilitate delivery
· Jacquemier’s (or Barnum’s) maneuver, where the posterior shoulder is delivered up and over the chest, then the shoulder and the rest of the baby, and
· Zavanelli’s maneuver, which is the most dangerous and used as a last resort. This involves pushing the baby’s head back into the vagina and performing a caesarean section.
The incidence of shoulder dystocia may lead to more serious injury, and may include:
· fractures of the clavicle (sometimes intentional to clear the cervix)
· fractures of the humerus (sometimes intentional to clear the cervix)
· temporary or permanent injury involving the brachial plexus nerves (brachial plexus injury or Erb’s Palsy) that attach to the spine in the upper, middle and lower trunk, and run through the shoulder and down to the arms and hands.
· hypoxia leading to brain damage or
Deliveries with shoulder dystocia occur in both diabetic and non-diabetic mothers. The incidence is greater in diabetic mothers who deliver larger babies. If you are at high risk for delivering a baby with shoulder dystocia, your health care provider should perform an ultrasound to determine if the baby’s size will be a problem. Your physician should also discuss if a large episiotomy will be necessary or if a planned caesarean section will be the best way to safeguard the health of the child. Caesarean sections are not always the practical solution for all cases, but if the birth weight of the infant is high (macrosomia), maternal obesity exists, the mother has gestational diabetes, and/or there is a previous history of shoulder dystocia, then a caesarean section may be indicated.