CASC Knowledge Essentials11 · Perinatal psychiatry: illness, medication and the newborn
11 · Perinatal psychiatry: illness, medication and the newborn
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Written by Resident Doctor Committee · Published
11.1 The postnatal differential
Presentation | Course | Distinguishing features |
|---|---|---|
Baby blues | First few days; resolves within two weeks | Tearfulness and lability without sustained severe depression or psychosis |
Postnatal depression | May start antenatally or during the first postnatal year | Persistent low mood/anhedonia, depressive thinking, impaired function |
Postpartum psychosis | Often abrupt in the first two weeks | Mania, mixed or depressive illness with delusions, hallucinations, disorganisation or rapidly changing state |
Perinatal OCD | Starts/worsens in pregnancy or after birth | Unwanted intrusions with rituals, reassurance seeking or avoidance |
Delirium | Acute, fluctuating | Impaired attention/awareness with a medical or drug-related cause |
Service definitions of perinatal illness are broader than some diagnostic onset windows. Depression several months after birth still needs perinatal care.
Sleep gives a useful distinction: inability to sleep despite opportunity suggests depression/anxiety; reduced need for sleep without fatigue, with increased energy, suggests mania. Perplexity can occur in postpartum psychosis, but poor attention, fever, seizures or neurological signs require urgent medical investigation.
11.2 Postnatal depression
More than exhaustion
Around 10–15% of women develop postnatal depression. Look for sustained low mood or loss of interest, with changes in energy, sleep, appetite, concentration, psychomotor activity, self-worth and thoughts of death. The usual minimum duration is two weeks; severe shorter presentations still need urgent care.
The content often centres on parenting: failure, excessive guilt, no pleasure with the baby, or believing the family would be better off without her. Anxiety is common. Lack of immediate affection alone does not diagnose depression or predict abuse.
Previous depression, antenatal anxiety/depression, poor support, relationship difficulties, domestic abuse and major stress raise vulnerability. Anaemia, thyroid disease, birth complications, pain and substances can mimic or worsen symptoms. Previous mania/hypomania changes the formulation and antidepressant plan.
Screening and treatment
Whooley questions and GAD-2 identify possible symptoms; EPDS and PHQ-9 help assess severity/change. Scores support assessment but cannot override psychosis, suicidality or inability to provide care.
Less severe illness may respond to facilitated self-help or CBT. More substantial depression may need an antidepressant or combined treatment, guided by previous response and preference. Psychotic depression, catatonia, food refusal or life-threatening risk may require admission and ECT. A mother and baby unit supports inpatient treatment and the relationship, with supervision matched to risk.
11.3 Postpartum psychosis
Usually an affective psychosis
Think bipolar pattern: elevated/irritable mood, markedly reduced sleep, racing thoughts, increased activity, or rapidly alternating manic and depressive symptoms. Delusions may concern the baby's identity, supernatural importance or danger. Hallucinations, suspiciousness, bizarre behaviour and lost insight can emerge over hours.
Suspected postpartum psychosis requires immediate specialist assessment, within four hours of referral under NICE guidance. Exclude infection, eclampsia, metabolic/thyroid disturbance, intoxication, withdrawal and neurological illness.
Risk and recurrence
Bipolar I, schizoaffective disorder, previous postpartum psychosis and close family history increase risk. RCPsych estimates approximately 1 in 1,000 births overall and 1 in 2 recurrence after a previous episode. These are population estimates; bipolar II carries less risk than bipolar I.
A belief that death will save the baby differs fundamentally from a feared, unwanted harm obsession. Consider suicide, accidental injury, neglect and delusion/command-driven harm. Risk changes quickly; family support protects only if it can deliver the care needed.
Treatment and prevention
Admission is usually required. Antipsychotics treat acute psychosis/mania; lithium may treat affective illness and prevent relapse. ECT is an option for severe, resistant or urgently life-threatening illness. Restoring sleep helps but does not replace treatment of the syndrome.
Previous postpartum psychosis warrants a specialist pregnancy/delivery plan: medication, early postnatal review, protected sleep and feeding. Prophylaxis may continue through pregnancy or begin immediately after birth, depending on illness outside the puerperium and relapse history. Being well antenatally does not remove postpartum risk.
11.4 Perinatal OCD versus psychosis
Obsessions conflict with the person's wishes. She may fear that having the thought means she is dangerous. Checking, avoidance and mental rituals briefly reduce distress but maintain the cycle.
Feature | Harm obsession | Psychotic belief/command |
|---|---|---|
Experience | Intrusive, unwanted, frightening | True, externally imposed or authoritative |
Response | Avoidance, checking, reassurance, neutralising | May act on the belief to “rescue” or protect the baby |
Insight | Often recognises excessiveness; can be poor | Reality testing impaired |
Associated syndrome | Anxiety, compulsions, exhaustion | Mania, severe depression, hallucinations, disorganisation |
Risk meaning | Thought alone is not intent; assess secondary harm/comorbidity | Impaired judgement, commands and delusions can create direct danger |
Themes include contamination, checking breathing, accidental injury and violent/sexual intrusions. People with OCD do not characteristically act on ego-dystonic harm obsessions. Rituals or avoidance can still disrupt feeding, sleep and care; comorbid depression adds suicide risk. Distinguish the obsession from any separate intent.
Treat with CBT using exposure and response prevention, with an SSRI according to severity, preference and past response. ERP reduces avoidance/rituals; repeated reassurance maintains them. Poor insight does not automatically turn an obsession into a delusion. Consider depressive rumination, generalised anxiety and birth-related PTSD.
11.5 Medication in pregnancy: the reasoning that changes decisions
The comparison is treated versus untreated illness, including relapse. Every pregnancy carries background miscarriage/malformation risks. Separate structural abnormalities, neonatal adaptation and later development; exposure timing matters.
A successful medicine and previous relapse history carry weight. Switching may destabilise the mother and expose the fetus to multiple drugs. Aim for an effective, simple regimen rather than an ineffective low dose. Abrupt self-discontinuation is generally unsafe.
Lithium
First-trimester lithium increases cardiac-malformation risk. In one large cohort, rates were 2.41% versus 1.15% of live births; the adjusted increase was smaller than the raw ratio, with a suggested dose relationship. These study-specific figures replace older exaggerated estimates of Ebstein's anomaly risk.
Lithium is not absolutely contraindicated. NICE generally reserves offering it for when antipsychotics have been ineffective; continuation may be appropriate with high relapse risk and a uniquely good response. Other options include gradual switching or selected interruption/restart. Stopping cannot undo exposure already sustained.
Renal clearance explains the monitoring: levels may fall during pregnancy, then rise after delivery. Dehydration, vomiting, infection and interacting drugs can cause toxicity. Plan delivery and prompt postpartum dose review. Arrange fetal assessment through obstetric/fetal medicine services. Neonatal effects include hypotonia, poor feeding, respiratory difficulty and thyroid disturbance.
NICE specifies levels every four weeks, then weekly from 36 weeks, and withholding lithium during labour with fluid/level monitoring. The final delivery plan follows specialist protocols; dose changes follow levels and clinical state.
Valproate
Maternal exposure causes birth defects in about 11%, and developmental problems in about 30–40%. Defects include neural-tube, cardiac and craniofacial abnormalities. Folic acid or a normal anomaly scan cannot remove neurodevelopmental risk. Valproate is contraindicated for bipolar disorder in pregnancy; suspected pregnancy needs urgent specialist review and a safe change/stop plan.
Situation | Requirement |
|---|---|
Able to become pregnant | Pregnancy Prevention Programme; other treatments ineffective/not tolerated; contraception, informed discussion and risk documentation |
New treatment below 55 | Two independent specialists document the required exceptional justification |
Men already taking valproate | February 2025 removed the two-specialist review requirement for this group; new starts below 55 remain subject to it |
Paternal precautions: effective contraception during treatment and for three months after stopping; no sperm donation during that period. Usual advice is condoms plus the female partner's contraception. MHRA says condoms are unnecessary for pregnancy prevention where there is no pregnancy risk or the partner already uses highly effective contraception.
The possible paternal neurodevelopmental association remains precautionary, with uncertain causality. It is different from the established maternal risk.
Other mood stabilisers and antipsychotics
Lamotrigine levels change during pregnancy and after birth; review levels and symptoms. It is not an acute antimanic drug. Carbamazepine is generally avoided for mental illness in pregnancy because of fetal and interaction risks.
Choose antipsychotics using previous response and individual risk. Weight gain and gestational diabetes matter, particularly with medicines such as olanzapine. Third-trimester exposure can cause neonatal adaptation or extrapyramidal effects; the neonatal team needs the medication history.
11.6 Antidepressants and breastfeeding: avoid blanket rules
SSRIs can be used in pregnancy when indicated. Some outcome associations are difficult to separate from maternal illness and other factors. Late exposure can cause transient neonatal adaptation: jitteriness, altered tone, feeding or respiratory difficulties. Persistent pulmonary hypertension is uncommon; UKTIS/BUMPS discusses a risk around 1 in 300 exposed babies.
SSRI/SNRI use in the month before delivery is associated with a small increase in postpartum haemorrhage risk, partly related to platelet effects. This informs obstetric planning rather than automatically requiring withdrawal.
Medicine | Breastfeeding point |
|---|---|
Sertraline/paroxetine | Preferred SSRIs for healthy term infants: low milk exposure; monitor feeding, weight and behaviour |
Fluoxetine | Cautious use possible; long half-life/active metabolite favour accumulation, but previous good response may favour continuation |
Sedating antipsychotics | Individual assessment; monitor alertness, feeding, growth; avoid bed-sharing on sedating medication |
Lithium | Usually avoided; selected use needs specialist supervision and infant monitoring |
Methadone/buprenorphine | Generally compatible in stable treatment; assess other substances and monitor infant |
Breastfeeding does not routinely require stopping an SSRI. SPS advice principally concerns healthy term infants; prematurity, illness and multiple medicines need additional advice. Low milk transfer and low placental transfer are different claims.
Lithium needs a more careful answer
NICE's routine advice excludes lithium from medicines on which breastfeeding is encouraged. SPS permits selected use only with extreme caution, specialist supervision and strict infant monitoring, including lithium, renal and thyroid tests. Infant dehydration or infection increases toxicity risk. Thus it is neither routine practice nor absolutely impossible.
11.7 Opioid dependence in pregnancy and neonatal withdrawal
Maintain stability
Methadone and buprenorphine are accepted pregnancy treatments. Adequate maintenance reduces instability, overdose and uncertain street exposure. Dose to control withdrawal and illicit use; an arbitrarily low dose may fail both. Pregnancy can increase dose requirements or favour split dosing.
Usually continue the effective substitution medicine. Switching from methadone to buprenorphine can precipitate withdrawal because of high receptor affinity. Detoxification, if chosen, is an individual specialist plan, often considered in the second trimester, with attention to relapse. It is not abrupt self-detoxification.
Neonatal opioid withdrawal
Think high-pitched cry, tremor, irritability, increased tone, poor feeding/sleep, vomiting or diarrhoea. Onset is often in the first few days but may be later with long-acting drugs or combined exposures. Observe the baby; not all exposed infants need medication. Prematurity, infection and metabolic illness remain differentials.
Breastfeeding during stable methadone/buprenorphine treatment is generally supported and may reduce withdrawal severity. Monitor feeding, alertness, breathing and weight; ongoing non-prescribed substances may change the decision. Abruptly stopping breastfeeding can itself precipitate withdrawal in some exposed infants.
Alcohol dependence needs medically assisted withdrawal. Cocaine/stimulants add placental-abruption, growth and prematurity risks; injecting adds infection and blood-borne viruses. Safeguarding rests on actual care and available support. Substitution treatment is not proof of inability to parent.