[6] There is no agreement in the evidence about risk factors, though a number of studies have suggested that sleep loss, first pregnancies (primiparity), and previous episodes of PPP may play a role.

[2] More recent reviews have added to growing evidence that prior psychiatric diagnoses, especially bipolar disorder, in the individual or her family may raise the risk of a new-onset psychosis triggered by childbirth.

[6] These may include, but are not limited to, a complete blood count, comprehensive metabolic panel, urinalysis and urine drug screen, and tests for thyroid functioning; further workup in the setting of classically neurological symptoms (such as delirium-like confusion) may include magnetic resonance imaging (MRI), a test of cerebrospinal fluid (CSF), or electroencephalogram (EEG).

[6] Research has shown strong evidence for the effectiveness of lithium as monotherapy in preventing repeat episodes of psychosis, particularly when compared to antipsychotic use alone,[2][6][10] and current recommendations suggest it as a first-line treatment for PPP in patients for whom this is safe[2][4][6] (lithium is not advised for patients with severe kidney or heart disease, thyroid dysfunction, Brugada syndrome, or who have known allergies to the drug).

[28] Stopping lithium requires slow and gradual discontinuation; sudden removal of the medication may lead to symptom relapse and suicidal thoughts.

[35] There is currently no consensus to the safety or level of lithium present in breastmilk, though several guidelines and reviews do not consider it an absolute danger to the infant which should exclude its use.

[36] Short-acting benzodiazepines, like lorazepam, are preferred from this class of drugs as they demonstrate lower levels passed through breastmilk and no reported side effects in infants.

[11] The first month following childbirth is associated with a higher relative risk for hospital admission due to psychosis when compared to other times in an individual's life.

[43] Between the 16th and 18th centuries, about 50 brief reports regarding postpartum psychosis were published; among them is the observation that these psychoses could recur,[44] and that they occur both in breast-feeding and non-lactating women.

[50][51] About 40% of patients experiencing postpartum bipolar disorder have puerperal mania,[52][53]: 217  with increased energy or activity and sociability, reduced need for sleep, rapid thinking and pressured speech, euphoria and irritability, loss of inhibition, violence, recklessness and grandiosity (including religious and expansive delusions); puerperal mania is considered to be particularly severe, with highly disorganized speech, extreme excitement and eroticism.

[citation needed] In the past, some experts regarded this as pathognomonic (specific) for puerperal psychosis, but this syndrome is found in other settings, not just the reproductive process, and in men.

Clinical assessment requires obtaining the history from the mother herself and, because she is often severely ill, lacking in insight and unable to give a clear account of events, from at least one close relative.

In the 10th edition of the International Classification of Diseases, published in 1992, the recommendation is to classify these cases by the form of the illness, without highlighting the postpartum state.

The American Psychiatric Association's Diagnostic and Statistical Manual, whose 5th edition was published in May 2013, allows the use of a 'peripartum onset specifier' in episodes of mania, hypomania or major depression if the symptoms occur during pregnancy or the first four weeks of the puerperium.

[69] The evidence for a trigger acting in pregnancy is also based on the large number of reported cases, and particularly on the frequency of mothers experiencing two or more prepartum episodes.

[86] It has been recognized since the 19th century[87] that it is optimal for a woman with puerperal psychosis to be treated at home, where she can maintain her role as homemaker and mother to her other children, and develop her relationship with the new-born.

[99] Aberrant steroid hormone–dependent regulation of neuronal calcium influx via extracellular matrix proteins and membrane receptors involved in responding to the cell's microenvironment might be important in conferring biological risk.

Since almost all reproductive onsets occur when the menstrual cycle is released from a long period of inhibition, this may be a common factor, but it can hardly explain episodes starting in the 2nd and 3rd trimesters of pregnancy.

[80] Research is needed to improve the care and treatment of affected mothers, but it is of paramount importance to investigate the causes, because this can lead to long term control and elimination of the disease.

It is important that the clinical study is also 'state-of-the-art'– that scientists understand the complexity of these psychoses, and the need for multiple and reliable information sources to establish the diagnosis.

[51]: 200–204  The clinical picture is usually delirium – a global disturbance of cognition, affecting consciousness, attention, comprehension, perception and memory – but amnesic syndromes and a mania-like state[51]: 25  also occur.

Donkin psychosis may not be rare: a British series included 13 possible cases;[51]: 35  but clarifying its distinction from postpartum bipolar disorder requires prospective investigations in collaboration with obstetricians.

But these cases continue to be reported – more than 50 in this century – from all over the world, including some from countries with advanced medical services;[122] most are due to rehydration without vitamin supplements.

[125] Psychosis is occasionally associated with other arterial or venous lesions: epidural anaesthesia can, if the dura is punctured, lead to leakage of cerebrospinal fluid and subdural haematoma.

[51]: 63–65 The most recent form of organic childbearing psychosis to be described is encephalitis associated with antibodies to the NMDA receptor; these women often have ovarian teratomas.

This form of chorea was caused by streptococcal infections, which at present respond to antibiotics; it still occurs as a result of systemic lupus or anti-phospholipid syndromes.

Lindsay Marie Clancy (née Musgrove;[138] born August 11, 1990) is an American woman from Duxbury, Massachusetts who strangled her three children on the evening of January 24, 2023.

Charlotte Perkins Gilman, in her short story "The Yellow Wallpaper" (1892) described severe depression with psychotic features starting after childbirth, perhaps similar to that experienced by the author herself.

Stacey Slater, a fictional character in the long-running BBC soap-opera EastEnders had postpartum psychosis in 2016, and was one of the show's biggest storylines that year.

Several nations including Canada, United Kingdom, Australia, and Italy recognize postpartum mental illness as a mitigating factor in cases where mothers kill their children.