Shoulder Dystocia
District 1 ACOG
Medical Student Education Module 2011
Definition
 Difficulty in delivery of fetal shoulders
 Failure to deliver fetal shoulder without
utilizing facilitating maneuvers
 Prolonged head-to-body delivery time
 >60 seconds
 Incidence: 0.2-3% of all live births;
represents an obstetric emergency
Pathophysiology
 Size discrepancy between fetal shoulders
and maternal pelvic inlet
 Macrosomia
 Large chest:BPD
 Absence of truncal rotation
 Fetal shoulders remain A-P or descent
simultaneously
Risk Factors
 Antepartum
 Macrosomia (>4500g)
 DM/GDM (increases overall risk by 70%)
 Multiparity
 Intrapartum
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Prolonged deceleration phase of labor
Prolonged 2nd stage
Protracted descent
Operative delivery (vacuum>forceps)
Risk factors cont…
 No evidence based data:
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Male
AMA
Short maternal stature
Abnormal pelvic shape/size
Unpredictable
 25-50% have no defined risk factor!
 50% of cases occur in infants whose birth
weight is <4000g
 84% of patients did not have prenatal dx.
of macrosomia by US
 82%of infants with brachial plexus palsy
did not have macrosomia
Complications
 Maternal
 Hemorrhage
 4th degree laceration
 Fetal
 Fx of humerus or clavicle
 Brachial plexus injury (Erb’s/Klumpke’s
palsy)
 Asphyxia/cord compression
 Physician
 Litigation: 11% of all obstetrical suits
Management
 Goal: Safe delivery before neontal
asphyxia and/or cortical injury
 7 minutes!!!
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Episiotomy
Suprapubic Pressure
McRoberts Maneuver
Woods or Rubin Maneuvers
Zavenelli
 Push back the delivered fetal head into birth
canal and perform an emergent c/s
McRoberts Maneuver
 42% success rate
 + Suprapubic pressure = 54-58%
 Brings pelvic inlet and outlet into more vertical
alignment
 Flattens sacrum
 Cephalad rotation of pubic symphysis
 Elevates anterior shoulder and flexes fetal spine
 Increases IUP by 97%
 Increases amplitude of contractions
 +31N of pushing force
Summary
 Cannot accurately predict
 BE PREPARED!
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Consider risk factors
Be prepared to perform various maneuvers
Diagnose and treat quickly
Obtain assistance from nursing staff and
NICU
HELPER Algorithm
 H: Call for Help; Shoulder dystocia is
called if shoulders cannot be delivered
with gentle traction
 E: Evaluate for Episiotomy: Not routinely
indicated; maybe needed when
attempting intra-vaginal maneuver
 L: Legs (McRoberts): Hyperflexion and
abduction of hips—initial maneuver
HELPER Algorithm cont.
 P (Suprapubic Pressure): No fundal pressure;
combination of McRoberts and suprapubic
pressure resolves most shoulder dystocias
 Enter (Internal Maneuvers):
 Woods: Insert hand into posterior vagina and rotate
posterior shoulder clockwise or counterclockwise
 Rubin: Push posterior or anterior shoulder toward
fetal chest to adduct shoulders
 Remove: Delivery posterior arm
Prophylactic Cesarean?
 Not recommended by ACOG
 Exceptions:
 Consider if…
 >5000g in mother without DM
 >4500g in mother with DM
Prolog Question #1
 A 25 year-old healthy woman has a normal
labor and a spontaneous delivery of the fetal
head. On expulsion of the head, a shoulder
dystocia is recognized. Before instituting
maneuvers the next step is to:
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A) Tell the patient not to push
B) Apply fundal pressure
C) Increase or initiate Oxytocin administration
D) Cut a large episiotomy
Answer
 A) Tell the patient not to push
 The training and experience of clinician
should dictate sequence of maneuvers that
will be used; however, initially it is best to do
nothing that will further impact the anterior
shoulder above the pubic symphysis. The
simplest way to avoid further impaction is to
ask the patient to stop pushing.