How is postpartum depression diagnosed?

Bottom linePostpartum depression is diagnosed by screening (usually the 10-question EPDS at postpartum and pediatric visits; 10+ flags follow-up) followed by a clinical assessment for depressive symptoms lasting two weeks or more, plus blood tests to rule out thyroid problems and anemia that can mimic it.

In two steps: a screening questionnaire to flag who needs a closer look, then a clinical conversation to make the actual diagnosis. No blood test or scan diagnoses PPD - though your doctor may run labs to rule out look-alikes.

Step 1: Screening

The standard tool is the Edinburgh Postnatal Depression Scale (EPDS) - 10 questions about the past week, scored 0-30. Most providers screen routinely at the 6-week postpartum visit and at pediatric checkups; ACOG recommends screening at least once in the postpartum period. Scores of 10-12 suggest possible depression, 13+ probable, and any answer above "never" on the self-harm question gets attention regardless of the total. You can take the EPDS privately before any appointment - bringing the score along is genuinely useful.

Step 2: Clinical assessment

A positive screen leads to a conversation about symptoms and duration. The clinical bar for postpartum depression is depressive symptoms most of the day, most days, for at least two weeks - low mood, loss of interest or pleasure, guilt, hopelessness, sleep and appetite changes beyond newborn logistics, difficulty bonding, or thoughts of self-harm. Timing distinguishes it from the baby blues, which peak in the first week and resolve by two weeks.

Ruling out the mimics

Good workups check for thyroid dysfunction (postpartum thyroiditis is common and can look exactly like depression), anemia (fatigue, fog), and vitamin deficiencies. That's usually one blood draw.

What happens after diagnosis

A plan matched to severity: support groups and talking therapy for milder cases, medication for moderate-to-severe (many antidepressants are breastfeeding-compatible), and urgent specialist care for safety concerns. Screening exists because treatment works - and because "just tired" hides a lot.

Related: postpartum depression quiz (EPDS) · signs of postpartum depression · when to seek help