What is the differential diagnosis and management of postpartum headaches?

Postpartum Headache Differential Diagnosis

Immediate Life-Threatening Causes to Exclude First

Use the PARTUM mnemonic to systematically rule out dangerous secondary causes before attributing headache to benign etiologies. 1, 2

Critical Red Flags Requiring Urgent Neuroimaging

• Focal neurological deficits, visual changes, altered consciousness, or seizures mandate immediate brain imaging to evaluate for stroke, hemorrhage, or venous thrombosis 3, 1
• Non-orthostatic headache that develops after initial orthostatic headache requires neuroimaging 3
• Headache onset more than 5 days after suspected dural puncture should prompt imaging 3, 1
• New headache with hypertension must be considered preeclampsia until proven otherwise 1
• Unexplained fever, impaired memory, or focal neurological symptoms are indications for further investigation including neuroimaging, blood samples, or lumbar puncture 3

Structured Differential Diagnosis Using PARTUM Mnemonic

P - Pressure (Preeclampsia/Eclampsia)

• New-onset headache with hypertension and proteinuria in the postpartum period 1, 4, 2
• Accounts for approximately 24% of postpartum headaches requiring hospitalization 4
• Can occur up to 6 weeks postpartum, not just immediately after delivery 4

A - Anaesthetic (Post-Dural Puncture Headache)

• Positional headache worse when upright, better when supine 1, 2
• Typically occurs within first 5 days of neuraxial procedure 3, 1
• Associated with neck stiffness and subjective hearing symptoms 1
• Comprises approximately 16% of postpartum headaches requiring hospitalization 4
• Important caveat: PDPH is associated with serious acute complications including subdural hematoma, cerebral venous sinus thrombosis, bacterial meningitis, and chronic headache disorders 5

R - Reversible Cerebral Vasoconstriction Syndrome

• Thunderclap headache pattern is a key red flag 3
• May present with features mimicking migraine but with atypical characteristics 3

T - Thrombosis (Cerebral Venous Sinus Thrombosis, Ischemic Stroke)

• Accounts for serious cerebral pathology in approximately 10% of patients requiring imaging 4
• Can present initially as postural headache that becomes continuous, then develops neurological symptoms 6
• 68% of patients who underwent cerebral imaging for refractory headache or neurological deficits had abnormal findings 4

U - Use Your Brain (Other Secondary Causes)

• Bacterial meningitis: fever, meningismus, altered mental status 2
• Subarachnoid hemorrhage: thunderclap onset, severe intensity 3
• Intracranial hemorrhage or mass lesions: progressive worsening, focal deficits 4

M - Migraine and Primary Headache Disorders

Migraine

• Most common benign cause, accounting for approximately 47% of postpartum headaches (combined with tension-type headache) 4
• Unilateral, pulsating quality, moderate to severe intensity 3
• Aggravated by routine physical activity 3
• Accompanied by nausea, vomiting, photophobia, or phonophobia 3

Tension-Type Headache

• Bilateral, mild to moderate pain with pressing or tightening quality 3
• Not aggravated by routine physical activity 3
• Lacks the accompanying symptoms of migraine 3

Medication-Overuse Headache

• Develops from overuse of acute medications: NSAIDs ≥15 days/month or triptans ≥10 days/month 1, 7
• Important differential for chronic headache patterns 3

Clinical Approach Algorithm

Step 1: Assess Timing and Characteristics

• Mean onset of significant postpartum headache is 3.4 days after delivery (range 2-32 days) 4
• Determine if headache is positional (suggests PDPH) or non-positional 1

Step 2: Check Blood Pressure and Proteinuria

• If hypertensive with proteinuria, treat as preeclampsia with antihypertensives and magnesium sulfate, not simple analgesics 1

Step 3: Evaluate for Neuraxial Procedure History

• If epidural or spinal anesthesia was performed, consider PDPH 3, 1
• Anesthesia consultation needed if PDPH suspected; approximately 80% require epidural blood patch if conservative management fails 1

Step 4: Screen for Red Flags

• Perform focused neurological examination looking for focal deficits, visual changes, altered consciousness 3, 1
• Check for fever and signs of meningismus 2

Step 5: Neuroimaging Indications

• MRI preferred over CT for higher resolution without ionizing radiation 3
• Required for: refractory headache despite initial therapy, any neurological deficit, non-orthostatic pattern after initial orthostatic headache, or onset >5 days post-dural puncture 3, 4

Common Pitfalls to Avoid

• Discharging patients with simple analgesics without excluding secondary causes, particularly preeclampsia in hypertensive women 1
• Assuming all postpartum headaches are benign primary headaches without systematic evaluation 4, 2
• Missing the transition from PDPH to serious complications like cerebral venous thrombosis when headache pattern changes from positional to continuous 6, 5
• Failing to obtain neuroimaging in patients with refractory headache or any neurological symptoms, as 68% will have abnormal findings 4
• Attributing headache to tension-type without considering bacterial meningitis in patients with fever and meningismus 2