Trauma During Pregnancy

Learning objectives

After completing this chapter, you should be able to apply the trauma primary survey to pregnancy; account for pregnancy-related anatomic and physiologic changes; recognize placental abruption, uterine rupture, fetomaternal hemorrhage, and preterm labor; use fetal assessment and observation appropriately; understand imaging and Rh considerations; identify intimate-partner violence; and select a destination that can manage both maternal injury and obstetric complications.

Opening transport scenario

A 27-year-old patient at 30 weeks is the restrained driver in a high-speed collision. She is awake with left upper-quadrant pain, seatbelt bruising, and uterine tenderness. Heart rate is 116/min, BP 112/72 mm Hg, and SpO₂ is 96%. Fetal heart rate is initially 150/min but develops recurrent late decelerations. The maternal blood pressure appears acceptable, yet the mechanism, abdominal findings, and fetal response suggest significant occult injury or placental compromise.

1. Core trauma principles

• Resuscitate the mother using standard trauma priorities.
• Relieve aortocaval compression after mid-pregnancy with left uterine displacement or safe lateral tilt.
• Do not withhold indicated imaging or procedures because of pregnancy.
• Use maternal and fetal findings together to guide destination and urgency.
• Assume more than one mechanism can coexist: hemorrhage, abruption, rupture, head injury, thoracic injury, and shock.

2. Pregnancy changes that affect trauma assessment

3. Primary survey and immediate interventions

Airway with cervical-spine protection

Use standard indications for airway control. Preoxygenate aggressively, anticipate a smaller airway, and minimize repeated attempts. Maintain spinal alignment when indicated.

Breathing

Treat tension pneumothorax, open pneumothorax, massive hemothorax, or flail physiology without delay. Thoracic procedures use standard indications; pregnancy should not postpone lifesaving decompression.

Circulation and hemorrhage

Control external bleeding, apply pelvic stabilization when indicated, obtain vascular access, activate blood products early for suspected major hemorrhage, and use maternal positioning to improve venous return. Avoid relying on crystalloid as definitive treatment of hemorrhagic shock.

Disability and exposure

Assess GCS, pupils, glucose, seizure, and neurologic deficit. Fully expose the patient while preventing hypothermia. Inspect the abdomen, back, perineum, and extremities.

4. Obstetric complications after trauma

5. Fetal assessment and observation

After the maternal primary survey and initial stabilization, assess fetal heart rate and uterine activity when gestational age and resources allow. The 2025 EAST guideline supports formal observation for at least 4–6 hours in viable pregnancies after trauma, with longer monitoring when contractions, bleeding, tenderness, ruptured membranes, nonreassuring fetal status, or significant mechanism is present.

• Verify the fetal signal and distinguish it from maternal pulse.
• Document baseline, variability, accelerations, decelerations, contractions, and uterine tone.
• Recognize that an initially normal tracing does not exclude later abruption.
• Use fetal findings as an additional vital-sign system—not as a substitute for maternal assessment.

6. Imaging and diagnostic evaluation

Medically indicated imaging should not be withheld because of pregnancy. Ultrasound and MRI can be useful, but CT may be the fastest and most accurate test for serious maternal injury. Minimize unnecessary exposure while prioritizing maternal diagnosis.

• FAST/POCUS may identify free fluid, pericardial effusion, pneumothorax, and fetal activity but cannot exclude all injury or abruption.
• Obtain CBC, metabolic panel, coagulation studies, fibrinogen, type and crossmatch, blood gas/lactate, urinalysis, and other mechanism-directed tests.
• Consider ECG and troponin for blunt cardiac injury.
• Use serial examinations and repeat diagnostics when the trajectory changes.

7. Rh status, Kleihauer-Betke testing, and Rh immune globulin

Determine maternal Rh status. Rh-negative, non-sensitized patients may need Rh immune globulin after trauma. The Kleihauer-Betke test or other quantification method can estimate fetomaternal hemorrhage and guide additional dosing; it is not a reliable screen for placental abruption or fetal well-being.

8. Special mechanisms

Blunt trauma

Motor-vehicle collisions, falls, assault, and crush injuries can cause maternal hemorrhage, abruption, uterine rupture, and fetal injury. Restraint use reduces risk; the lap belt belongs low across the hips, not over the uterus.

Penetrating trauma

Later in pregnancy, the enlarged uterus may shield some maternal abdominal organs but increases fetal and uterine exposure. Destination should prioritize trauma surgery and obstetric capability.

Burns and electrical injury

Treat maternal airway, carbon-monoxide exposure, fluid needs, temperature, and associated trauma. Fetal effects depend on maternal physiology, voltage/current path, gestational age, and injury severity.

Intimate-partner violence

Pregnancy does not protect against violence. Interview privately when feasible, use trauma-informed language, document objective findings, address immediate safety, and follow mandatory reporting and safeguarding requirements.

9. Destination and transport decisions

A severely injured pregnant patient generally needs the trauma center capable of definitive maternal care, with obstetric and neonatal resources involved as early as possible. Bypassing lifesaving trauma capability solely for an obstetric hospital can be harmful. Regional protocols should define when a combined trauma-obstetric center is available.

• Communicate gestational age, mechanism, maternal injuries, transfusion, fetal status, contractions, bleeding, Rh status, and imaging.
• Carry blood, airway equipment, pelvic binder, warming, fetal-monitoring capability, and delivery supplies as appropriate.
• Define diversion for hemorrhagic shock, fetal bradycardia, imminent birth, or loss of airway/ventilation.
• Avoid unnecessary scene or sending-facility delay for extensive nondefinitive testing.

10. Evolving case study

Phase 1: Maternal survey

The team applies manual uterine displacement, initiates blood-product readiness, and proceeds with CT because occult splenic injury is suspected. FAST is negative but does not end the evaluation.

Phase 2: Obstetric complication

Contractions increase and fetal late decelerations persist. Uterine tenderness raises concern for abruption despite limited external bleeding.

Phase 3: Destination

The patient is transported to a level I trauma center with obstetric surgery, blood bank, and NICU rather than a smaller obstetric-only facility. Trauma and obstetric teams receive a joint prearrival report.

11. High-yield chapter summary

1. Maternal resuscitation is the first fetal resuscitation.
2. Relieve aortocaval compression after mid-pregnancy.
3. Do not withhold indicated imaging or procedures.
4. Maternal hypotension may be late.
5. Abruption can occur without visible bleeding and may present later.
6. Fetal monitoring follows the maternal primary survey.
7. Viable pregnancies after trauma generally require at least 4–6 hours of formal observation, longer when concerning findings exist.
8. KB testing helps quantify fetomaternal hemorrhage; it does not rule out abruption.
9. Screen privately for intimate-partner violence when feasible.
10. Destination should prioritize definitive maternal trauma care while mobilizing obstetric and neonatal resources.

References

1. International Board of Specialty Certification. Maternal Fetal Transport Microcredential Candidate Handbook. Updated April 2026.
2. Eastern Association for the Surgery of Trauma. Trauma in Pregnancy: Systematic Review, Meta-analysis, and Practice Management Guideline. 2025.
3. American College of Obstetricians and Gynecologists. Guidelines for Diagnostic Imaging During Pregnancy and Lactation.
4. American College of Surgeons. Advanced Trauma Life Support.
5. American College of Obstetricians and Gynecologists. Guidance on intimate partner violence.