What is the most appropriate maneuver to help prevent shoulder dystocia during delivery in a pregnant woman with diabetes mellitus (DM) and obesity?

Management of Shoulder Dystocia in a Pregnant Woman with Diabetes and Obesity

Suprapubic pressure is the most appropriate maneuver to help prevent shoulder dystocia during delivery, used in conjunction with the McRoberts maneuver as first-line management. However, it is critical to understand that shoulder dystocia cannot truly be "prevented" during delivery—it is an unpredictable obstetric emergency that requires immediate recognition and systematic management 1, 2.

Understanding the Clinical Context

This patient has two major risk factors for shoulder dystocia:

• Diabetes mellitus increases the risk of fetal macrosomia and shoulder dystocia 2
• Obesity compounds this risk through its association with larger birth weight 3

However, 50-70% of shoulder dystocia cases occur in the absence of these risk factors, and most deliveries with these risk factors present do not result in shoulder dystocia 1. This underscores that shoulder dystocia remains largely unpredictable 1, 4.

Actual Prevention Strategies (Before Delivery Occurs)

The question asks about "prevention during delivery," but true prevention occurs before the delivery attempt:

Antepartum Management

• Optimize glycemic control with insulin (preferred agent), diabetic diet, and glucose monitoring to reduce macrosomia risk 3
• Recommend physical activity coupled with dietary measures in obese women to reduce fetal macrosomia and excessive weight gain 1
• Consider induction of labor at 39 weeks or more if the cervix is favorable in cases of impending macrosomia 1
• Recommend cesarean delivery in specific high-risk scenarios:
  • Estimated fetal weight >4,500g with maternal diabetes 1
  • Estimated fetal weight >5,000g without diabetes 1
  • History of shoulder dystocia with severe complications 1
  • Fetal macrosomia with failure to progress in second stage when fetal head station is above +2 1

Management Algorithm When Shoulder Dystocia Occurs

The question lists maneuvers that are actually used to resolve shoulder dystocia after it has occurred, not prevent it. Here is the evidence-based sequence:

First-Line Management

McRoberts maneuver (maternal thigh hyperflexion) with or without suprapubic pressure is recommended as the initial procedure 5, 1, 2, 4. This combination is:

• Simple to perform 4
• Effective in 88-90% of cases 6
• Associated with low morbidity 4

Second-Line Maneuvers (If McRoberts Fails)

The choice depends on whether the posterior shoulder is engaged 1, 4:

• If posterior shoulder is engaged: Perform Wood's maneuver (internal rotation) preferentially 1, 4
• If posterior shoulder is not engaged: Attempt delivery of the posterior arm preferentially 1, 4

All physicians and midwives should know at least two maneuvers beyond McRoberts 1, 4.

Third-Line and Rescue Maneuvers

• Gaskin maneuver (all-fours position) can be attempted 2
• Rubin maneuver (adduction of fetal shoulders) is a rotational technique 2
• Zavanelli maneuver (cephalic replacement) is a last-resort procedure when other maneuvers fail, followed by cesarean delivery 2

Critical Management Principles

What NOT to Do

• Avoid excessive traction on the fetal head 1, 4
• Do not perform fundal pressure (uterine expression) 1, 4
• Do not perform inverse rotation of the fetal head 1, 4

Essential Actions

• Unequivocally announce that shoulder dystocia is occurring 2
• Summon extra assistance immediately 2, 4
• Keep track of time from delivery of head to full delivery 2
• Call for pediatric support immediately 1
• Remain calm and work systematically through maneuvers 1, 4

Answering the Specific Question

Among the options listed:

• Suprapubic pressure is part of first-line management (with McRoberts) 1, 2, 4, 6
• Rubin maneuver is a second-line rotational technique 2
• Gaskin maneuver is a second or third-line option 2
• Zavanelli maneuver is a last-resort rescue procedure 2

The most appropriate answer is suprapubic pressure, as it is the only option listed that is part of the recommended first-line approach 1, 2, 4, 6. However, it must be emphasized that suprapubic pressure should be used in combination with McRoberts maneuver, not alone 1, 4.

Training and Preparedness

Implementation of practical training with simulation for all delivery room care providers is associated with significant reduction in neonatal injury 1. Every institution should practice these maneuvers during simulation exercises 2.