The Daily Differential — Saturday, September 26, 2026

Shoulder Dystocia

A shoulder dystocia can turn a routine birth into a time-critical emergency with fetal hypoxia, brachial plexus injury, or maternal hemorrhage. Coordinated maneuvers matter more than force.

Also known asimpacted shoulder · fetal shoulder dystocia

By the Blue Fish Med Desk Sep 26, 2026 · Phoenix

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The baby’s head delivers, then draws tightly back against the perineum. The room’s conversation stops as the nurse says the shoulders have not followed. The fetal monitor still sounds, but the next contraction is already building. Which move comes first?

— What’s your move? Read on.

Before you read

When should you move on from the initial maneuver?
What findings change the newborn and maternal priorities afterward?

When to Think of It

The head delivers but the shoulders do not with gentle axial traction; the head may retract against the perineum (“turtle sign”). Call shoulder dystocia when the shoulders fail to deliver promptly with routine gentle traction—not only after a fixed time has elapsed.

Sick or Not Sick

The key call is whether the shoulder is still impacted after the first maneuver. Announce the emergency, summon experienced obstetric, neonatal, and anesthesia help, and track time while moving through maneuvers without forceful traction.

The First Fifteen Minutes

Immediately: Call for help, stop pushing if directed, and begin McRoberts positioning—hyperflex the mother’s hips; add suprapubic pressure directed to dislodge the anterior shoulder. Do not apply fundal pressure or use excessive downward traction.
If unresolved, proceed promptly to internal rotational maneuvers (e.g., Rubin/Woods) or deliver the posterior arm; choose based on operator skill and fetal position. Move to hands-and-knees positioning if feasible.
Refractory dystocia: Consider terbutaline 0.25 mg subcutaneously once only if uterine relaxation may facilitate a maneuver; it is an adjunct, not a substitute for maneuvers, and may cause maternal tachycardia.
If the shoulders remain impacted despite appropriate maneuvers, the senior obstetrician directs rescue options; do not improvise forceful traction. Prepare neonatal resuscitation.

Definitive Care & Disposition

After delivery, assess the newborn promptly for respiratory compromise, clavicle or humeral injury, and brachial plexus dysfunction. Examine the mother for major lacerations and postpartum hemorrhage; quantify blood loss and manage complications. Document the sequence, timing, maneuvers, personnel, and maternal/newborn outcomes.

How This One Kills

Repeated downward traction or fundal pressure can worsen impaction and cause serious fetal injury or uterine rupture. The failure mode is escalating force instead of changing the mechanics.

The Differential — What Else Looks Like This

Nuchal cord — the cord is around the neck and the shoulders are not impacted; confusing it can delay the needed shoulder maneuvers.
Breech delivery difficulty — the body delivers before the head; the mechanics and rescue maneuvers differ, so misclassification wastes critical time.

The Second-Day Story

Dystocia may be recognized without a dramatic turtle sign, especially when the head delivers slowly or the shoulder obstruction is not immediately obvious. Do not wait for a particular visual cue or elapsed-time threshold: if routine gentle traction does not deliver the shoulders, call the emergency and begin the maneuver sequence.

Back to Our Patient

Back to our patient. The delivered head retracts tightly against the perineum, and gentle axial traction does not deliver the shoulders: recognize shoulder dystocia, call for help, and move immediately to McRoberts positioning with suprapubic pressure. When that does not resolve the impaction, the obstetrician proceeds to an internal rotational maneuver and delivers the baby without forceful traction. The neonatal team assesses the newborn, while the obstetric team checks the mother for trauma and hemorrhage; both remain for appropriate post-delivery observation.

Patient Presentation to Attending

How you’d present this patient on the floor — tight, pertinent positives and negatives, no rambling

“This is a term laboring patient with a vaginal delivery complicated by failure of the shoulders to deliver after the head emerged. The head has retracted against the perineum, and gentle axial traction has not delivered the shoulders. There is no evidence of a nuchal cord explaining the delay, and the fetal heart rate remains audible. I called the shoulder dystocia, stopped traction, and started McRoberts positioning with suprapubic pressure; the dystocia persists. I recommend proceeding immediately to an internal rotational maneuver or posterior-arm delivery with the senior obstetrician, while neonatal and hemorrhage teams prepare.”

Study Directive

From memory, list the first three shoulder dystocia maneuvers in order and name one rescue maneuver.
Practice a 20-second team callout that identifies the emergency, requests help, and assigns a timekeeper.
Review your institution’s shoulder dystocia documentation and newborn-examination process.

Recent Literature

Review or guideline Practice Bulletin No 178: Shoulder Dystocia
Obstet Gynecol, 2017 · PMID 28426618 · cited 161×

Use a stepwise sequence of delivery maneuvers when shoulder dystocia occurs, while avoiding excessive traction on the fetal head.

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Chest Pain in Pregnancy

Pregnancy and the postpartum period increase risk for thromboembolism, acute coronary syndromes, and aortic disease. Delayed diagnosis or withholding...

Listen: EM:RAP podcast →

0:00 / –:–– AI‑generated audio

The Case

At 29 weeks’ gestation, 31-year-old Maya grips the edge of the stretcher as a breath catches short. Her chest pain sharpens when she inhales; one calf is more swollen than the other. Her blood pressure is steady, and the first ECG is nondiagnostic. Which dangerous cause should be excluded first?

Before You Read

Which pregnancy-adapted approach can help decide whether pulmonary vascular imaging is needed?
Which findings make this an unstable patient rather than a diagnostic-workup patient?
When should pregnancy change your imaging or treatment plan—and when should it not?

Why It Matters

Pregnancy and the postpartum period increase risk for thromboembolism, acute coronary syndromes, and aortic disease. Delayed diagnosis or withholding indicated imaging can be more dangerous than the radiation exposure.

When to Think of It

Treat new chest pain, dyspnea, syncope, hypoxemia, or unexplained tachycardia in pregnancy or postpartum as potentially serious. Consider pulmonary embolism (PE), acute coronary syndrome (ACS), aortic dissection, pneumothorax, and peripartum cardiomyopathy—not just reflux or musculoskeletal pain.

Sick or Not Sick

The crucial fork is unstable versus stable. Shock, severe hypoxemia, ongoing ischemic symptoms, malignant arrhythmia, or suspected dissection demands resuscitation and immediate targeted evaluation; a stable patient can undergo a structured, diagnosis-directed workup.

The First Fifteen Minutes

Obtain ECG, serial high-sensitivity troponins, pulse oximetry, focused history/exam, and bedside cardiac/lung assessment as indicated. Give oxygen only for hypoxemia; do not delay chest radiography or definitive imaging solely because of pregnancy.
For suspected ACS, give aspirin 162–325 mg PO, chewed once, unless contraindicated; it inhibits platelet aggregation. For ongoing ischemic pain with adequate blood pressure and no contraindication, give nitroglycerin 0.4 mg SL every 5 minutes, up to 3 doses; it reduces preload and myocardial oxygen demand. If treating ACS with anticoagulation, use unfractionated heparin 60 units/kg IV (maximum 4,000 units), then 12 units/kg/hour IV (maximum 1,000 units/hour) per local ACS protocol; it limits thrombus propagation. Avoid nitrates with hypotension or recent phosphodiesterase-5 inhibitor use.
For suspected PE with high clinical concern and delayed imaging, if no major bleeding contraindication, start enoxaparin 1 mg/kg SC every 12 hours; it provides therapeutic anticoagulation. Do not anticoagulate reflexively if aortic dissection is a serious possibility.

Definitive Care & Disposition

In a stable patient with possible PE, consider pregnancy-adapted YEARS: assess signs of DVT, hemoptysis, and whether PE is the most likely diagnosis. With no YEARS criteria, a D-dimer below 1,000 ng/mL may exclude PE; with one or more criteria, the threshold is below 500 ng/mL (use the local assay and units). If not excluded, proceed to compression ultrasound when DVT symptoms are present and to appropriate chest imaging—V/Q scan or CT pulmonary angiography based on the clinical context and local pathway. For suspected ACS, involve cardiology and obstetrics early; pursue indicated angiography/reperfusion. Suspected dissection requires urgent definitive imaging and specialist care. Admit patients with confirmed or strongly suspected life-threatening disease; disposition depends on diagnosis, stability, and gestational age.

How This One Kills

Anchoring on pregnancy-related reflux, anxiety, or “normal” pregnancy tachycardia can delay recognition of PE, ACS, or dissection. Pregnancy is not a reason to withhold necessary imaging or treatment.

The Atypical Presentation

Pregnant and postpartum patients may have nonspecific dyspnea, fatigue, nausea, or mild tachycardia, while normal pregnancy itself can raise heart rate and D-dimer. Do not use a single symptom, normal oxygen saturation, or a nondiagnostic ECG to dismiss serious disease. Reassess the whole pattern, use a validated pregnancy-specific pathway where appropriate, and obtain definitive testing when indicated.

Back to Our Patient

Back to 31-year-old Maya, whose pleuritic pain and unilateral calf swelling make PE a leading concern despite stable vital signs and a nondiagnostic ECG. Recognize the possible PE, risk-stratify her as stable, and assess the DVT signs and other pregnancy-adapted YEARS items. Her symptoms include a clinical DVT sign, so the team obtains urgent compression ultrasound and proceeds to chest imaging when needed rather than dismissing the symptoms or delaying for pregnancy. With PE confirmed and no bleeding contraindication, she receives weight-based therapeutic anticoagulation and is admitted for obstetric and medical management.

Patient Presentation to Attending

“This is a 31-year-old at 29 weeks’ gestation with acute pleuritic chest pain and dyspnea, plus unilateral calf swelling. She is normotensive and not hypoxemic; ECG is nondiagnostic, and there is no ongoing ischemic pattern or reported abrupt tearing pain. The calf asymmetry raises concern for DVT and PE, and pregnancy does not lower that concern. I recommend pregnancy-adapted PE evaluation with compression ultrasound and definitive chest imaging if needed. If PE is confirmed and there is no bleeding contraindication, I will start therapeutic enoxaparin and admit with obstetric involvement.”

Study Directive

Write the three pregnancy-adapted YEARS items and both D-dimer thresholds from memory.
Practice an oral differential for pregnancy-associated chest pain that includes PE, ACS, dissection, and peripartum cardiomyopathy.
Review your local pathway for choosing V/Q scanning versus CT pulmonary angiography.

Key Medications

Aspirin: 162–325 mg PO, chewed once for suspected ACS if not contraindicated.
Nitroglycerin: 0.4 mg SL every 5 minutes, up to 3 doses for ongoing ischemic pain if blood pressure permits.
Unfractionated heparin (ACS): 60 units/kg IV bolus (maximum 4,000 units), then 12 units/kg/hour IV (maximum 1,000 units/hour); follow institutional protocol.
Enoxaparin (therapeutic PE): 1 mg/kg SC every 12 hours; adjust for renal function and follow local protocol. Pregnancy-specific anticoagulation decisions merit obstetric/hematology input.

High-Yield Pearls

Pregnancy-adapted YEARS uses different D-dimer thresholds depending on whether any YEARS criteria are present; do not apply a single cutoff indiscriminately.
A normal oxygen saturation or nondiagnostic ECG does not rule out PE.

The Mimics

GERD — burning discomfort linked to meals or recumbency without cardiopulmonary compromise; mislabeling ischemia or PE as reflux delays definitive care.
Musculoskeletal chest pain — reproducible focal tenderness supports the diagnosis but does not by itself exclude PE or ACS; premature closure is the danger.
Peripartum cardiomyopathy — heart-failure symptoms and reduced LV function distinguish it from isolated chest-wall pain; missing it risks rapid decompensation.
Aortic dissection — abrupt severe pain, pulse/BP differential, or neurologic deficit should redirect evaluation urgently; anticoagulating presumed PE before considering dissection can be catastrophic.

Board Question

A hemodynamically stable pregnant patient has pleuritic chest pain, unilateral calf swelling, and suspected PE. Imaging is not immediately available, and there is no major bleeding contraindication or concern for aortic dissection. Which treatment is appropriate while arranging definitive evaluation? -

AWithhold anticoagulation until after delivery -
BEnoxaparin 1 mg/kg SC every 12 hours -
CAspirin 81 mg PO daily as sole treatment -
DWarfarin loading dose

Reveal answer

Correct: B

Therapeutic low-molecular-weight heparin is an appropriate treatment for suspected or confirmed PE in pregnancy when anticoagulation is indicated. Warfarin is avoided during pregnancy, and aspirin is not adequate treatment for PE.

Recent Literature

Review or guideline Cardiovascular Emergencies in Pregnancy
Cardiol Clin, 2018

Use a pregnancy-specific approach to recognize and manage dangerous cardiac causes of chest pain, including acute coronary syndrome and aortic dissection.
Recent clinical Pregnancy-adapted YEARS Algorithm: A Retrospective Analysis
West J Emerg Med, 2024 · cited 5×

For pregnant patients with chest pain and suspected pulmonary embolism, the pregnancy-adapted YEARS pathway helps guide D-dimer testing and decisions about chest imaging.

Full text · open access

TheDaily Differential

Shoulder Dystocia

When to Think of It

Sick or Not Sick

The First Fifteen Minutes

Definitive Care & Disposition

How This One Kills

The Second-Day Story

Study Directive

Recent Literature

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