OB Nightmares: Shoulder Dystocia

Shoulder dystocia is a clinical obstetric emergency diagnosed when the anterior shoulder will not deliver after the head, often with the classic turtle sign. It is time critical, frequently unpredictable, and early team coordination matters in both tertiary centers and rural emergency departments.

Shoulder Dystocia Recognition and Response

• Clinical diagnosis only: Shoulder dystocia is diagnosed at the bedside when the anterior shoulder fails to deliver with traction after the head; imaging does not help and recognition has to be immediate.
• Turtle sign clue: Retraction of the fetal head back against the perineum is the named red flag that should make you think shoulder dystocia before more traction worsens impaction.
• Unreliable risk factors: Macrosomia, diabetes, excess maternal weight gain, protracted labor, and prior dystocia all raise concern, but more than half of cases occur without any risk factor at all.
• Immediate team actions: The first moves are to stop maternal pushing, call for obstetric and neonatal help, and start a timer and documentation, with the timing priorities laid out in the episode.
• Time-critical framing: Rapid delivery matters because prolonged impaction threatens both fetal oxygenation and maternal morbidity, and most successful resolutions happen within the first few minutes.

Core Maneuvers and Rescue Options

• McRoberts first maneuver: McRoberts changes pelvic mechanics by flattening the sacrum and rotating the pubic symphysis cephalad, making it a foundational first-line maneuver in shoulder dystocia.
• Suprapubic pressure direction: External pressure belongs over the suprapubic area and directed toward the fetal face to rotate the shoulder; fundal pressure is specifically contraindicated.
• Posterior arm delivery priority: Posterior arm delivery is a high-yield early maneuver because reducing that arm decreases the bisacromial diameter and often relieves the impaction quickly.
• Repeat attempt mindset: If the first pass fails, McRoberts and posterior arm delivery should be attempted again rather than abandoned too early. We get into the practical sequencing in the chapter.
• Advanced rotational maneuvers: Rubin, Woods corkscrew, and the Gaskin all-fours position are next-line options aimed at rotating or repositioning the shoulders when initial measures fail.
• Last-ditch salvage procedures: Intentional clavicle fracture, abdominal-assisted delivery, proctoepisiotomy, and pubic symphysiotomy exist for austere or catastrophic scenarios, but the decision boundaries are deliberately narrow.

References:

1.) American College of Obstetricians and Gynecologists. Shoulder dystocia. ACOG practice bulletin clinical management guidelines for obstetrician-gynecologists. Number 40, November 2002 (reaffirmed 2020). Obstet Gynecol. 2002;100:1045–50. 

2.) Poggi SH, Spong CY, Allen RH. Prioritizing posterior arm delivery during severe shoulder dystocia. Obstet Gynecol. 2003 May; 101: 1068-72.

3.) Gurewitsch ED, Kim EJ, Yang JH, Outland, KE, McDonald MK, Allen RH. Comparing McRoberts’ and Rubin’s maneuvers for initial management of shoulder dystocia: an objective evaluation. Am J Obset Gynecol. 2005; 192: 153.

4.) Bjorklund K. Minimally invasive surgery for obstructed labour: a review of symphiostomy during the twentieth century (including 5000 cases). BJOG. 2002; 109: 236.

5.) Rodis, John F. Shoulder dystocia: Intrapartum diagnosis, management and outcome. Ed Charles J Lockwood, Vanessa A Barss. UpToDate. Jun 2021. 

6.) Rodis, John F. Shoulder dystocia: Risk factors and planning delivery of high-risk pregnancies. Ed Charles J Lockwood, Vanessa A Barss. UpToDate. Jun 2021.