Perinatal Mood Disorders: PMHNP Board Review

Perinatal mood disorders span pregnancy and the postpartum period, and the board tests your ability to separate three distinct presentations. The single highest-yield point: postpartum psychosis is a psychiatric emergency with high risk of infanticide and suicide, requiring immediate hospitalization — distinct from the self-limited baby blues and from postpartum depression. This review covers the spectrum, screening with the EPDS, and treatment in pregnancy and lactation, including newer agents.

Epidemiology and risk factors

Postpartum depression affects roughly 10–15% of new mothers, making it one of the most common complications of childbirth, while postpartum psychosis is rare (about 1–2 per 1,000 births) but severe. The strongest predictor of perinatal depression is a prior history of depression or a prior perinatal mood episode, followed by current depressive or anxious symptoms during pregnancy, inadequate social support, stressful life events, unintended pregnancy, and a history of trauma. A personal or family history of bipolar disorder is the key risk factor for postpartum psychosis, and women with bipolar disorder face a substantially elevated risk of a postpartum episode — which is why eliciting any history of mania is part of every perinatal evaluation. Hormonal shifts, sleep deprivation, and the psychosocial demands of a newborn all contribute. Recognizing that these are real medical conditions, not character flaws, frames the board-appropriate, treatment-forward approach.

The perinatal mood spectrum

Baby blues

• Onset within the first few days postpartum; resolves by about 2 weeks.

• Mild mood lability, tearfulness, irritability, anxiety.

• Affects up to ~80% of new mothers — common and self-limited.

• Treatment: reassurance, support, monitoring. No medication needed. The key board contrast: blues are transient and do not impair functioning.

Postpartum depression (PPD)

• A major depressive episode with peripartum onset (DSM-5-TR specifier: onset during pregnancy or within 4 weeks postpartum; clinically often recognized up to 12 months).

• Symptoms persist beyond 2 weeks and cause impairment — depressed mood, anhedonia, guilt, sleep/appetite change, poor bonding, thoughts of harming self or infant.

• Requires active treatment; screen for suicidal and infanticidal ideation.

Postpartum psychosis

• A psychiatric emergency. Rapid onset, usually within the first 1–2 weeks postpartum.

• Delusions (often about the infant), hallucinations, disorganization, confusion, mood lability.

• High risk of suicide and infanticide.

• Strongly associated with bipolar disorder.

• Management: immediate hospitalization; mood stabilizers, antipsychotics, and consideration of ECT. Do not manage as outpatient.

Quick differentiation: transient and mild = blues; persistent depression past 2 weeks = PPD; psychosis/confusion within days to 2 weeks = emergency.

Screening

• Edinburgh Postnatal Depression Scale (EPDS): The most widely used, validated perinatal screening tool — a 10-item self-report. Item 10 screens for self-harm/suicidality and must always be reviewed.

• The PHQ-9 is also used.

• Screening is recommended during pregnancy and postpartum; a positive screen is not diagnostic — it prompts full evaluation.

• A complete perinatal assessment also screens for bipolar disorder (any history of mania/hypomania), because an antidepressant given to an unrecognized bipolar patient can precipitate a mood switch, and because bipolar history flags postpartum-psychosis risk. It also screens for anxiety, OCD (intrusive thoughts of harming the infant — typically ego-dystonic, in contrast to psychotic delusions), and substance use.

Perinatal anxiety and OCD

Anxiety disorders and OCD are common in the perinatal period and often coexist with depression. Postpartum OCD classically features distressing, intrusive, ego-dystonic thoughts of accidentally or intentionally harming the infant; the mother is horrified by these thoughts and takes steps to avoid the baby. This is a crucial board distinction from postpartum psychosis, where thoughts about harming the infant are driven by delusions and the mother lacks insight — the former is treated outpatient with SSRIs and therapy, while the latter is an emergency. Misreading ego-dystonic OCD thoughts as psychosis (or vice versa) is a classic trap, and the safe move is always a careful risk assessment.

Treatment in pregnancy and lactation

General principles

• Untreated maternal depression carries real risks (preterm birth, poor bonding, suicide), so treatment decisions weigh risks of illness against risks of medication — never a reflexive "stop all meds."

• Psychotherapy (CBT, interpersonal therapy) is first-line for mild-to-moderate illness and avoids medication exposure.

SSRIs

• SSRIs are generally first-line pharmacotherapy when medication is indicated. Sertraline is often preferred in lactation due to low milk transfer.

• Paroxetine is generally avoided in pregnancy (associations with cardiac malformations) — a frequently tested point.

• Late-pregnancy SSRI exposure can cause a transient neonatal adaptation syndrome (jitteriness, feeding/respiratory issues) that is usually self-limited; this is not a reason to abruptly stop a needed medication.

Newer agents — neuroactive steroids

• Brexanolone (IV): First FDA-approved drug specifically for postpartum depression; a GABA-A allosteric modulator given as a 60-hour infusion in a monitored setting (risk of excessive sedation/loss of consciousness).

• Zuranolone (oral): FDA-approved oral agent for postpartum depression, given as a 14-day course — rapid onset is a key advantage. Counsel on sedation and driving precautions.

Mood stabilizers (relevant to bipolar/postpartum psychosis)

• Lithium, valproate, and carbamazepine have teratogenic concerns (valproate is the most teratogenic and is generally avoided in people of childbearing potential when alternatives exist). Manage perinatal bipolar disorder with specialist input.

For agent fundamentals, see our PMHNP psychopharmacology high-yield guide and antipsychotic side effects review.

Breastfeeding and shared decision-making

Lactation questions reward a nuanced, individualized stance rather than blanket prohibition. Most SSRIs are considered compatible with breastfeeding, with sertraline and paroxetine showing the lowest relative infant doses; the infant should be monitored for sedation, feeding, and weight gain. The decision balances the benefits of breastfeeding, the mother's need for effective treatment, and minimal medication exposure — and it should be made collaboratively with the patient. Abruptly stopping a needed medication to breastfeed, or reflexively advising against breastfeeding because of any psychotropic, are both wrong answers. For the newer neuroactive steroids, counsel on sedation; zuranolone's short course and rapid onset make it attractive, but lactation data are still limited, so individualized counseling applies.

Nonpharmacologic and preventive care

Treatment is not only pharmacologic. Psychotherapy (CBT and interpersonal therapy) is first-line for mild-to-moderate perinatal depression and a valuable adjunct in all severities. Sleep protection, social support mobilization, partner and family involvement, and treatment of comorbid anxiety improve outcomes. For women at high risk (prior perinatal episode or bipolar history), the board favors a proactive plan: close monitoring, early intervention, and, in bipolar disorder, maintaining or restarting mood-stabilizing treatment around delivery under specialist guidance. ECT remains a safe, effective option for severe, psychotic, or treatment-resistant perinatal illness when rapid response is needed.

High-yield board pearls

• Postpartum psychosis = emergency, hospitalize; strongly linked to bipolar disorder.

• Baby blues resolve by ~2 weeks; PPD persists beyond and impairs function.

• EPDS is the validated perinatal screen; item 10 covers suicidality.

• Sertraline is often preferred in lactation; paroxetine is generally avoided in pregnancy.

• Brexanolone (IV) and zuranolone (oral) are the FDA-approved PPD-specific neuroactive steroids.

• Untreated maternal depression has its own serious risks — treat when indicated.

• Valproate is highly teratogenic and generally avoided in childbearing potential.

Common exam traps

• Treating postpartum psychosis as outpatient depression — it requires immediate hospitalization.

• Calling persistent postpartum depression "just the baby blues" past the 2-week mark.

• Stopping all medications during pregnancy reflexively, ignoring the risks of untreated illness.

• Choosing paroxetine in a pregnant patient.

• Missing item 10 of the EPDS (suicidality) on a positive screen.

• Overlooking bipolar disorder in a woman presenting with postpartum psychosis.

All perinatal prescribing must follow current guidelines and an individualized, shared risk-benefit discussion with the patient; this review presents board-level concepts, not treatment direction for a specific patient.

Keep building your board readiness

Perinatal questions reward fast triage of the three presentations, knowing the EPDS, and reasoning through medication safety rather than blanket avoidance. Reinforce these with focused practice. Explore the full PMHNP question bank and study tools, find your weak areas with a quick diagnostic assessment, or review the related substance use disorders board review. Ready to start drilling? Create a free account.