What is the appropriate management for a 35-year-old postpartum woman with symptoms of depressed mood, fatigue, and a gravelly voice?

Evaluation and Management of Postpartum Depression with Hypothyroidism

This patient requires immediate thyroid function testing (TSH, free T4) before any psychiatric intervention, as her constellation of symptoms—depressed mood, fatigue, and gravelly voice occurring 14 months postpartum—strongly suggests postpartum thyroiditis or hypothyroidism, which can fully mimic depression. 1

Immediate Diagnostic Workup

Thyroid Assessment (Priority #1)

• Order TSH and free T4 immediately, as hypothyroidism presents with depressed mood, fatigue, and voice changes (gravelly voice from myxedematous vocal cord changes) 2
• Postpartum thyroiditis occurs in 5-10% of women, typically manifesting 1-4 months postpartum but can present up to 12 months after delivery 1
• The gravelly voice is a critical physical finding suggesting laryngeal myxedema, which does not occur in primary psychiatric depression 3

Depression Screening

• Administer the Edinburgh Postnatal Depression Scale (EPDS) to establish baseline severity, as this 10-question tool has 95% sensitivity and 93% specificity for postpartum depression 3, 1
• A score ≥10 indicates possible depression requiring further evaluation; scores ≥11 maximize combined sensitivity and specificity 3
• The EPDS is available in over 60 languages and evaluates symptoms over the past 7 days 3, 1

Safety Assessment

• Screen for suicidal ideation immediately, as suicide risk is elevated in both untreated depression and untreated thyroid disease 4, 5
• Assess for psychotic symptoms, as postpartum psychosis affects 1-2 per 1000 births and represents a psychiatric emergency 6

Treatment Algorithm Based on Findings

If Hypothyroidism is Confirmed (TSH elevated, low free T4)

• Initiate levothyroxine replacement therapy first and reassess mood symptoms after achieving euthyroid state (typically 6-8 weeks) 2
• Many depressive symptoms will resolve with thyroid hormone replacement alone 2
• If depressive symptoms persist after thyroid normalization, proceed to antidepressant therapy 7

If Thyroid Function is Normal and EPDS ≥10

For moderate depression (EPDS 10-14):

• Initiate sertraline 25-50 mg daily, as it is the preferred SSRI for postpartum women due to minimal passage into breast milk and decades of safety data 1, 5
• Sertraline is FDA-approved for major depressive disorder and is compatible with breastfeeding 5
• Titrate to therapeutic dose (typically 50-200 mg daily) over 2-4 weeks based on response 5

For severe depression (EPDS ≥15):

• Start sertraline immediately at 50 mg daily and refer to psychiatry within 1 week 4, 1
• Consider sick leave for 2-4 weeks minimum, as denying leave for functionally impairing depression is ethically inappropriate 4

Concurrent Psychotherapy

• Refer for cognitive behavioral therapy (CBT) or interpersonal therapy, which are first-line evidence-based treatments with efficacy comparable to pharmacotherapy 4, 7
• Supportive counseling combined with pharmacotherapy is more effective than either modality alone 2, 7
• Telemental health interventions show equivalent efficacy to in-person care for postpartum depression 3

Medication Management Specifics

Sertraline Dosing and Monitoring

• Use therapeutic doses for at least 4-6 weeks before declaring treatment failure; do not underdose 8, 9
• Most patients require 50-200 mg daily for adequate response 5
• Continue medication for 6-12 months postpartum to ensure complete recovery and prevent recurrence 7, 9
• Monitor for serotonin syndrome (agitation, confusion, racing heartbeat, muscle rigidity) especially if patient takes other serotonergic medications 5

Breastfeeding Considerations

• Sertraline is compatible with breastfeeding according to the American Academy of Pediatrics, with low breast milk concentrations 8, 5
• The risk of untreated maternal depression (impaired maternal-infant bonding, adverse effects on infant cognitive and emotional development) generally outweighs minimal medication risks 1, 10

Follow-Up Schedule

Initial Phase (First 4 Weeks)

• Reassess within 1-2 weeks after initiating any treatment to monitor for symptom improvement, medication side effects, and suicidal ideation 1, 5
• If thyroid replacement initiated, recheck TSH at 6-8 weeks 2
• Repeat EPDS at each visit to track response objectively 3, 1

Maintenance Phase

• Depression prevalence peaks at 12 weeks postpartum (17.4%) and continues rising through the first year, requiring ongoing surveillance 1
• Schedule monthly follow-ups during first 3 months of treatment, then every 2-3 months if stable 9
• Screen for comorbid anxiety disorders, which occur in approximately 16% of postpartum women 1

Critical Pitfalls to Avoid

• Do not attribute all symptoms to depression without ruling out hypothyroidism—the gravelly voice is a red flag for organic thyroid disease 3, 2
• Do not underdose antidepressants or discontinue prematurely—inadequate treatment leads to chronic, recurrent, refractory depression 7, 9
• Do not dismiss symptoms as "normal postpartum adjustment" when they persist beyond 2 weeks and cause functional impairment 1, 6
• Do not overlook the impact on infant development—untreated maternal depression adversely affects infant cognitive, behavioral, and emotional outcomes 1, 10
• Do not abruptly discontinue sertraline—taper gradually to avoid withdrawal symptoms including anxiety, irritability, dizziness, and electric shock-like sensations 5

Documentation Requirements

• Document EPDS score, thyroid function results, and any safety concerns 1
• Record functional impairment specifically (ability to care for infant, perform daily activities) 4
• Create safety plan if suicidal ideation present 4, 5
• Establish clear treatment plan with scheduled reassessments 1