Oh, and here is a little article about it-it says having a cesarean or induction for expected macrosomia does NOT lessen the incidence of shoulder dystocia.
Evidence is lacking to support labor induction or elective cesarean delivery in women without diabetes who are at term when a fetus is suspected of having macrosomia.14 In two studies of 313 women without diabetes, induction for suspected fetal macrosomia did not lower the rates of shoulder dystocia or cesarean delivery, nor did it improve the rates of maternal or neonatal morbidity.15 [strength of recommendation (SOR) evidence level A, meta-analysis] While labor induction in women with gestational diabetes who require insulin may reduce the risk of macrosomia and shoulder dystocia, the risk of maternal or neonatal injury is not modified. Not enough evidence is available to routinely support elective delivery in this population.16,17 [SOR evidence level B, systematic review including a single randomized trial]
In women without diabetes, labor induction for suspected fetal macrosomia does not lower the rates of shoulder dystocia or cesarean delivery.
Similarly, prophylactic cesarean delivery is not recommended as a means of preventing morbidity in pregnancies in which fetal macrosomia is suspected.9 [SOR evidence level C, expert opinion based on cost-effectiveness analysis] Analytic decision models have estimated that 2,345 cesarean deliveries, at a cost of nearly $5 million annually, would be needed to prevent one permanent brachial plexus injury in a patient without diabetes who had a fetus suspected of weighing more than 4,000 g. In the subgroup of women with diabetes, the frequency of shoulder dystocia, brachial plexus palsy, and cesarean delivery was higher, leading the authors to conclude that a policy of elective cesarean delivery in this group potentially may have greater merit.9 [SOR evidence level C, expert opinion based on cost-effectiveness analysis]
And this is what it says about treatment in the case of SD:
H Call for help.
This refers to activating the pre-arranged protocol or requesting the appropriate personnel to respond with necessary equipment to the labor and delivery unit.
E Evaluate for episiotomy.
Episiotomy should be considered throughout the management of shoulder dystocia but is necessary only to make more room if rotation maneuvers are required. Shoulder dystocia is a bony impaction, so episiotomy alone will not release the shoulder. Because most cases of shoulder dystocia can be relieved with the McRoberts maneuver and suprapubic pressure, many women can be spared a surgical incision.
L Legs (the McRoberts maneuver)
This procedure involves flexing and abducting the maternal hips, positioning the maternal thighs up onto the maternal abdomen. This position flattens the sacral promontory and results in cephalad rotation of the pubic symphysis. Nurses and family members present at the delivery can provide assistance for this maneuver.
P Suprapubic pressure
The hand of an assistant should be placed suprapubically over the fetal anterior shoulder, applying pressure in a cardiopulmonary resuscitation style with a downward and lateral motion on the posterior aspect of the fetal shoulder. This maneuver should be attempted while continuing downward traction.
E Enter maneuvers (internal rotation)
These maneuvers attempt to manipulate the fetus to rotate the anterior shoulder into an oblique plane and under the maternal symphysis (see Figure 2). These maneuvers can be difficult to perform when the anterior shoulder is wedged beneath the symphysis. At times, it is necessary to push the fetus up into the pelvis slightly to accomplish the maneuvers.
R Remove the posterior arm.
Removing the posterior arm from the birth canal also shortens the bisacromial diameter, allowing the fetus to drop into the sacral hollow, freeing the impaction. The elbow then should be flexed and the forearm delivered in a sweeping motion over the fetal anterior chest wall. Grasping and pulling directly on the fetal arm may fracture the humerus.
R Roll the patient.
The patient rolls from her existing position to the all-fours position. Often, the shoulder will dislodge during the act of turning, so that this movement alone may be sufficient to dislodge the impaction. In addition, once the position change is completed, gravitational forces may aid in the disimpaction of the fetal shoulders.