What is the evaluation and management of a 37-week pregnant woman presenting to the Emergency Department (ED) with back pain and possible labor?

Evaluation and Management of a 37-Week Pregnant Woman with Back Pain and Possible Labor in the ED

A 37-week pregnant woman presenting to the ED with back pain and possible labor requires immediate assessment for true labor, preeclampsia, and other pregnancy complications, with prompt obstetrical consultation if labor is confirmed or complications are identified. 1

Initial Assessment

• Obtain vital signs including blood pressure to assess for hypertension (≥140/90 mmHg), which may indicate preeclampsia 2
• Evaluate for signs of labor: regular uterine contractions, cervical dilation, or rupture of membranes 1
• Assess fetal status with electronic fetal monitoring if available in the ED 1
• Determine if back pain is related to labor, musculoskeletal causes, or other pregnancy complications 3, 4

Differentiating Back Pain Causes

• Labor-related back pain: typically rhythmic, may radiate to abdomen, and increases in intensity with time 4
• Musculoskeletal back pain: often related to pregnancy-induced hyperlordosis, ligamentous laxity, and anterior pelvic tilt 4
• Pathological causes: consider preeclampsia, placental abruption, or other pregnancy complications if accompanied by concerning symptoms 2, 1

Evaluation for Preeclampsia

• Check for hypertension (BP ≥140/90 mmHg) and assess for severe features (BP ≥160/110 mmHg) 2
• Look for early warning signs: severe headache, visual disturbances, epigastric pain, or altered mental status 2
• If preeclampsia is suspected, immediate delivery is recommended at ≥37 weeks gestation regardless of severity 5
• Obtain laboratory tests if preeclampsia is suspected: complete blood count, liver enzymes, creatinine, and urine protein 2

Management Algorithm

If True Labor is Suspected:

1. Confirm labor status through:

   • Assessment of regular, progressive contractions
   • Cervical examination (if no contraindications like placenta previa) 1
   • Rupture of membranes assessment

2. If labor is confirmed:

   • Arrange immediate transfer to labor and delivery unit 1
   • Consult obstetrics for further management 1
   • Consider Group B Streptococcus (GBS) prophylaxis if indicated and time permits 2

If Preeclampsia is Suspected:

1. Immediate blood pressure control if severe hypertension (≥160/110 mmHg for >15 minutes) 2

   • First-line medications: IV labetalol or oral nifedipine 2
   • Do not use methyldopa for urgent BP reduction 2

2. Assess for severe features requiring immediate intervention:

   • Neurological symptoms (severe headache, visual changes)
   • Pulmonary edema
   • Liver involvement or thrombocytopenia 2, 5

3. At 37 weeks, immediate delivery is recommended for women with preeclampsia 5

If Musculoskeletal Back Pain Without Labor:

1. Perform focused physical examination to identify pain source 3, 4
2. Consider non-pharmacological interventions:
   • Position changes and rest
   • Heat therapy
   • Supportive devices 3, 6
3. Medication options (limited in pregnancy):
   • Acetaminophen as first-line analgesic 3
   • Avoid NSAIDs near term due to potential complications 1

Special Considerations

• For Rh-negative mothers, consider anti-D immunoglobulin if trauma is involved 1
• If domestic violence is suspected, screen appropriately as pregnancy increases risk 1
• MRI is the safest imaging modality if advanced imaging is needed for back pain evaluation 3

Disposition

• Patients in active labor: transfer to labor and delivery 1
• Patients with preeclampsia at 37 weeks: admit for delivery 5
• Patients with uncomplicated musculoskeletal back pain: may discharge with appropriate follow-up and return precautions 6, 4
• Patients with concerning symptoms but not in labor: consider observation and obstetrical consultation 1

Return Precautions

• Return immediately for:
  • Regular, painful contractions
  • Rupture of membranes
  • Decreased fetal movement
  • Vaginal bleeding
  • Worsening back pain unresponsive to conservative measures
  • Headache, visual changes, or epigastric pain 2, 1