Brain structure in women at risk of postpartum psychosis: an MRI study

Familial Risk of Postpartum Psychosis

OBJECTIVE

Postpartum psychosis is one of the most severe psychiatric conditions, with high risks of suicide and infanticide if untreated. Although genetic factors contribute to the risk of postpartum psychosis, the extent of familial risk remains to be determined. The authors compared relative recurrence risk across different family relationship types, hypothesizing that relative recurrence risk for postpartum psychosis varies by degree of genetic relatedness and is higher in female full siblings than in cousins.

METHODS

This cohort study consisted of 1,648,759 women from the Swedish nationwide registers, of whom 2,514 (0.15%) experienced postpartum psychosis within 3 months of their first-ever childbirth. The authors estimated the relative recurrence risk of postpartum psychosis for female full siblings and cousins as a measure of familial risk.

RESULTS

The relative recurrence risk of postpartum psychosis in full siblings was 10.69 (95% CI=6.60, 16.26) when adjusted for year of and age at childbirth. Although cousins showed an elevated relative recurrence risk, these results did not reach statistical significance (1.78, 95% CI=0.70, 3.62). Despite the higher familial risk of postpartum psychosis among full siblings, the absolute risk for women with an affected sibling was relatively low, estimated at 1.60% within the entire population.

CONCLUSIONS

The observed increased risk of postpartum psychosis in full siblings suggests both genetic and shared environmental influences. However, the lack of significant results in cousins hampers a more accurate distinction between these factors. Furthermore, despite increased relative recurrence risk in siblings, their overall likelihood of developing postpartum psychosis remains low. This study underscores the need for further research to better understand the intricate interplay of genetics and shared environment in the development of postpartum psychosis.

The parental brain, perinatal mental illness, and treatment: A review of key structural and functional changes

The transition to parenthood is perhaps the only time in adult life when the brain changes to such a significant degree in such a short period, particularly in birthing parents. It is also a time when there is an increased risk of developing a mental illness, which may be due, in part, to the increased neuroplasticity. Thus, we must develop interventions and treatments that support parents and promote parental brain health. This review will highlight key findings from current research on how human brain structure and function are modified with 1) the transition to parenthood, 2) parenting stress and perinatal mental illness, and 3) treatments aimed at promoting perinatal mental health. The focus will be on birthing parents and mothers, but brain changes in non-birthing parents will also be discussed. Improvements in our understanding of the parental brain, in health and with illness, will promote the well-being of generations to come.

Familial risk of postpartum psychosis

Objective

Postpartum psychosis, a mood disorder triggered by childbirth, is one of the most severe psychiatric conditions, with high risks of suicide and infanticide if untreated. While it is evident that genetic factors play a crucial role in disorder risk, the exact extent of their importance is yet to be determined.

Methods

This cohort study consisted of 1,648,759 women from the Swedish nationwide registers, of whom 2,514 (0.15%) experienced postpartum psychosis within three months of their first-ever childbirth. We estimated the relative recurrence risk of postpartum psychosis for female full siblings and cousins as a measure of familial, genetic, and environmental risk.

Results

Relative recurrence risk of postpartum psychosis in full siblings was 10.69 (95% CI=6.60-16.26) when adjusted for year of and age at childbirth. Although cousins showed an elevated relative recurrence risk, these results did not reach statistical significance (1.78, 95% CI=0.70-3.62). Despite the higher familial risk of postpartum psychosis among full siblings, the absolute risk for women with an affected sibling is relatively low, estimated at 1.55% within the entire population.

Conclusions

The observed increased risk of postpartum psychosis in full siblings suggests both genetic and shared environmental influences. However, the lack of significant results in cousins hampers a definitive distinction between these factors. Furthermore, despite increased relative recurrence risk in siblings, their overall likelihood of developing postpartum psychosis remains low. Our study underscores the need for further research to better understand the intricate interplay of genetics and environment in the development of postpartum psychosis.

Postpartum Psychosis: A Proposed Treatment Algorithm

Background

Postpartum psychosis (PPP) is a psychiatric emergency that generally warrants acute inpatient care. PPP is marked by the sudden onset of affective and psychotic symptoms with a rapid deterioration in mental state. Evidence suggests that PPP is a discrete disorder on the bipolar disorder spectrum with a distinct treatment profile and prognosis.

Methods

We conducted a PubMed database search for various terms involving PPP and its treatment and included peer-reviewed articles published in English.

Objective

To provide a treatment algorithm for the management of PPP based on available evidence.

Results

Pharmacological therapy is the mainstay of PPP management in the acute phase. Evidence points to a combination of antipsychotics and lithium in the acute treatment of PPP. Electroconvulsive therapy can offer a rapid treatment response where required. Lithium appears to have the best evidence for relapse prevention and prophylaxis in PPP. Psychoeducation is essential and psychosocial interventions used in bipolar disorder may be effective in PPP.

Conclusion

Early detection and prompt treatment with antipsychotics and lithium, followed by maintenance treatment with lithium, is associated with a favourable prognosis in PPP.Reprinted from J Psychopharmacol 2023; 37:960-970, with permission from Sage Journals. Copyright © 2023.

Postpartum Psychosis: A Review of Risk Factors, Clinical Picture, Management, Prevention, and Psychosocial Determinants

Postpartum psychosis is rare, but is a serious clinical and social problem. On its own, it is not included in DSM-5 (Diagnostic and Statistical Manual of Mental Disorders) or ICD-10 (International Statistical Classification of Diseases and Related Health Problems) as a disease entity, and current diagnostic criteria equate it with other psychoses. This poses a serious legal problem and makes it difficult to classify. The disorder is caused by a complex combination of biological, environmental, and cultural factors. The exact pathophysiological mechanisms of postpartum psychosis remain very poorly understood. There is a need for further research and increased knowledge of the medical sector in the prevention and early detection of psychosis to prevent stigmatization of female patients during a psychiatric episode. It is necessary to regulate its position in the DSM5 and ICD-10. Attention should be paid to the social education of expectant mothers and their families. This article aims to review the current status of risk factors, prevention, and management of postpartum psychosis.

Postpartum psychosis: A proposed treatment algorithm

BACKGROUND

Postpartum psychosis (PPP) is a psychiatric emergency that generally warrants acute inpatient care. PPP is marked by the sudden onset of affective and psychotic symptoms with a rapid deterioration in mental state. Evidence suggests that PPP is a discrete disorder on the bipolar disorder spectrum with a distinct treatment profile and prognosis.

METHODS

We conducted a PubMed database search for various terms involving PPP and its treatment and included peer-reviewed articles published in English.

OBJECTIVE

To provide a treatment algorithm for the management of PPP based on available evidence.

RESULTS

Pharmacological therapy is the mainstay of PPP management in the acute phase. Evidence points to a combination of antipsychotics and lithium in the acute treatment of PPP. Electroconvulsive therapy can offer a rapid treatment response where required. Lithium appears to have the best evidence for relapse prevention and prophylaxis in PPP. Psychoeducation is essential and psychosocial interventions used in bipolar disorder may be effective in PPP.

CONCLUSION

Early detection and prompt treatment with antipsychotics and lithium, followed by maintenance treatment with lithium, is associated with a favourable prognosis in PPP.

Fleur G, Mukona L, Hernandez E, Lamberty N. Peripartum Complications as Risk Factors for Postpartum Psychosis: A Systemic Review

The aim of this research paper is to conduct a systematic review of periparturient complications as risk factors of postpartum psychosis. The investigation of risk factors for maternal psychosis following childbirth is complicated by the risk of confounding by a previous psychiatric history; therefore, this systematic review focuses on labor complications as risk factors among women without any previous psychiatric hospitalizations or diagnoses.

Articles were collected and analyzed from the PubMed, MEDLINE, and Cochrane Review Library databases, as well as Clinicaltrials.gov, in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Article abstracts and article titles of the identified publications were screened independently by all seven authors, and studies were selected if they met the following inclusion criteria: patients were diagnosed with postpartum psychosis per the guidelines in the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM-V), DSM-IV or World Health Organization’s ICD-10 Classification of Mental and Behavioral Disorders; patients presented with no prior psychiatric diagnoses, hospitalizations or history; and the study evaluated the association of periparturient complications to first-onset postpartum psychosis, excluding narrative reviews, systematic reviews, or meta-analyses.

Fifteen case-control, cohort, and case report studies, with thousands of patients, were selected to investigate the correlation between perinatal complications and first-onset post-partum psychosis. Obstetric complications during childbirth significantly predisposed for postpartum psychosis in certain individual studies but did not reveal an association in others.

More studies must be implemented to elaborate on this limited scope.

Decreased brain functional connectivity associated with cognitive dysfunction in women with second pregnancy

Purpose

Previous research has found that women with second pregnancy may have an increased risk of cognitive dysfunction. This study aims to investigate the intrinsic functional connectivity (FC) pattern of the DMN anchored on posterior cingulate cortex (PCC) in postpartum women, especially the parous women using resting-state functional magnetic resonance imaging (rs-fMRI).

Methods

Twenty parous women, 26 primiparous women, and 30 nulliparous women were included for rs-fMRI scan. They were age and education well matched. A seed based FC method was conducted to reveal FC patterns with other brain regions using a region of interest in the PCC. The relationships between FC patterns and cognitive performance were further detected.

Results

Relative to primiparous women, parous women had significantly decreased FC primarily between the PCC and the right middle frontal gyrus and right parahippocampal gyrus. The decreased FC to the right parahippocampal gyrus in parous women was positively associated with the reduced DST scores (rho = 0.524, p = 0.031). Moreover, parous women compared with nulliparous women showed significantly decreased FC between the PCC and the left superior frontal gyrus and left middle frontal gyrus. The reduced FC to the left superior frontal gyrus in parous women was also positively associated with the lower DST scores (rho = 0.550, p = 0.022).

Conclusion

Our result highlights that women with second pregnancy revealed decreased FC between the DMN regions with the parahippocampal gyrus and prefrontal cortex, which was correlated with specific impaired cognitive function. This study may provide new insights into the neuropathological mechanisms of postpartum cognitive impairment and enhance our understanding of the neurobiological aspects during postpartum period.

Recent Neuroscience Advances in Human Parenting

The transition to parenthood entails brain adaptations to the demands of caring for a newborn. This chapter reviews recent neuroscience findings on human parenting, focusing on neuroimaging studies. First, we describe the brain circuits underlying human maternal behavior, which comprise ancient subcortical circuits and more sophisticated cortical regions. Then, we present the short-term and long-term functional and structural brain adaptations that characterize the transition to motherhood, discuss the long-term effects of parenthood on the brain, and propose several underlying neural mechanisms. We also review neuroimaging findings in biological fathers and alloparents (such as other relatives or adoptive parents), who engage in parenting without directly experiencing pregnancy or childbirth. Finally, we describe perinatal mental illnesses and discuss the neural responses associated with such disorders. To date, studies indicate that parenthood is a period of enhanced brain plasticity within brain areas critical for cognitive and social processing and that both parenting experience and gestational-related factors can prime such plasticity.

Association between symbol digit modalities test and regional cortex thickness in young adults with relapsing-remitting multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system, predominating within young adults. Cognitive disorders are common in MS and have are associated with several Magnetic Resonance Imaging (MRI) markers, especially brain atrophy. Many have found the symbol digit modalities test (SDMT) to be the most sensitive individual cognitive measure relevant to MS. However, the relationship between SDMT and regional brain cortex thickness in young adults with relapsing-remitting multiple sclerosis (YA-RRMS) has been little explored. The purpose of this study was to investigate the association between the SDMT and regional cortex thickness in YA-RRMS by FreeSurfer, which is an automatic brain structure segmentation method.

METHOD

Twenty-eight YA-RRMS patients (18-35 years old) were enrolled in the present study. Informed consent and information including gender, age, disease duration, number of relapses, annual relapse rate was collected from all patients. Clinical cognitive evaluations (SDMT and auditory verbal learning test (AVLT)) and daily performance: activities of daily living (ADL) were assessed in the present study. MRI scans were performed at the Institute of Neurosurgery of Tiantan Hospital. Twenty-eight matched healthy controls (HC) MRI data were obtained from Tiantan Hospital database. Data on thirty-four points of bilateral cortical structure thickness using statistically defined brain regions-of-interest from FreeSurfer were obtained from all participants.

RESULTS

Patients with RRMS exhibited extensively thinner cerebellar cortex compared with HC. SDMT scores were significantly correlated with AVLT subentries (IM, immediate memory; DRM, delayed recall memory; LTRM, long-term recognition memory) in YA-RRMS patients (P < 0.05). SDMT was strongly correlated with regional cortex thickness differences of the right temporal pole (r = 0.68) and bilateral parahippocampal areas (right r = 0.62; left r = 0.60), and moderately correlated with regional cortex thickness differences including the left superior temporal and right insula (r = 0.57 and 0.56, respectively) in YA-RRMS patients.

CONCLUSION

The present study has shown the SDMT is strongly correlated with selected cortex regions including the bilateral parahippocampal area and the right temporal pole which are involved in geometric structures processing.

Neurocognitive correlates of working memory and emotional processing in postpartum psychosis: an fMRI study

BACKGROUND

Postpartum psychosis (PP) is a severe postpartum disorder. While working memory and emotional processing-related brain function are consistently impaired in psychoses unrelated to the puerperium, no studies have investigated them in PP.

METHODS

Twenty-four women at risk of developing PP (11 developed an episode - PE; 13 remained well - NPE) and 20 healthy postpartum women completed two functional magnetic resonance imaging tasks within a year of delivery: working memory (n-back) and emotional face recognition (fearful faces). We compared women at-risk of PP to controls, as well as NPE, PE, and controls to test for potential effects of a PP episode occurrence.

RESULTS

Women at-risk of PP and PE showed hyperactivation of lateral visual areas, precuneus, and posterior cingulate during the n-back task. The at-risk group as a whole, as well as the PE and NPE groups, showed hyperconnectivity of the right dorsolateral prefrontal cortex (DLPFC) with various parieto-occipito-temporo-cerebellar regions compared to controls during several n-back conditions. Increases in connectivity between the right DLPFC and ipsilateral middle temporal gyrus were observed in the PE group compared to NPE during 2-back. During the fearful faces task, at-risk women as a group showed hyperactivation of fronto-cingulo-subcortical regions, and hypoconnectivity between the left amygdala and ipsilateral occipito-parietal regions compared to controls. No significant performance differences were observed.

CONCLUSIONS

These results present preliminary evidence of a differential nature of functional brain abnormalities in PP compared to the typically observed reduced connectivity with the DLPFC in psychoses unrelated to puerperium, such as bipolar disorder.

Risk factors for postpartum relapse in women at risk of postpartum psychosis: The role of psychosocial stress and the biological stress system

BACKGROUND

Postpartum psychosis is the most severe psychiatric disorder associated with childbirth, and the risk is particularly high for women with a history of bipolar disorder, schizoaffective disorder or those who have suffered a previous episode of postpartum psychosis. Whilst there is a lot of evidence linking stress to psychosis unrelated to childbirth, the role of stress in the onset of postpartum psychosis has not been fully investigated.

METHODS

A prospective longitudinal study of 112 pregnant women, 51 at risk of postpartum psychosis because of a DSM-IV diagnosis of bipolar disorder (n = 41), schizoaffective disorder (n = 6) or a previous postpartum psychosis (n = 4) and 61 healthy women with no past or current DSM-IV diagnosis and no family history of postpartum psychosis. Women were followed up from the third trimester of pregnancy to 4 weeks' post partum. Women at risk who had a psychiatric relapse in the first 4 weeks' post partum (AR-unwell) (n = 22), were compared with those at risk who remained well (AR-well) (n = 29) on measures of psychosocial stress (severe childhood maltreatment and stressful life events) and biological stress (cortisol and inflammatory biomarkers).

RESULTS

Logistic regression analyses revealed that severe childhood maltreatment (OR = 4.9, 95% CI 0.5-49.2) and higher daily cortisol in the third trimester of pregnancy (OR=3.7, 95% CI 1.2-11.6) predicted psychiatric relapse in the first 4 weeks' post partum in women at risk of postpartum psychosis after adjusting for clinical and sociodemographic covariates.

CONCLUSION

The current study provides evidence for the role of psychosocial stress and the biological stress system in the risk of postpartum relapse in women at risk of postpartum psychosis.

Altered dynamics of the prefrontal networks are associated with the risk for postpartum psychosis: a functional magnetic resonance imaging study

Postpartum psychosis (PP) is a severe mental disorder that affects women in the first few weeks after delivery. To date there are no biomarkers that distinguish which women at risk (AR) develop a significant psychiatric relapse postpartum. While altered brain connectivity may contribute to the risk for psychoses unrelated to the puerperium, this remains unexplored in PP. We followed up 32 AR and 27 healthy (HC) women from pregnancy to 8-week postpartum. At this point, we classified women as AR-unwell (n = 15) if they had developed a psychiatric relapse meeting DSM-IV diagnostic criteria, or impacting on daily functioning and requiring treatment, or AR-well (n = 17) if they remained asymptomatic. Women also underwent an fMRI scan at rest and during an emotional-processing task, to study within- and between-networks functional connectivity. Women AR, and specifically those in the AR-well group, showed increased resting connectivity within an executive network compared to HC. During the execution of the emotional task, women AR also showed decreased connectivity in the executive network, and altered emotional load-dependent connectivity between executive, salience, and default-mode networks. AR-unwell women particularly showed increased salience network-dependent modulation of the default-mode and executive network relative to AR-well, who showed greater executive network-dependent modulation of the salience network. Our finding that the executive network and its interplay with other brain networks implicated in goal-directed behavior are intrinsically altered suggest that they could be considered neural phenotypes for postpartum psychosis and help advance our understanding of the pathophysiology of this disorder.

Neurobiology of peripartum mental illness

At least one in seven pregnant or recently postpartum women will experience a mental illness such as an anxiety disorder, depressive disorder, or substance use disorder. These mental illnesses have detrimental effects on the health of the mother, child, and family, but little is known about the hypothalamic and other neural correlates of maternal mental health concerns. The transition to parenthood alone is a time of remarkable neural plasticity, so it is perhaps not surprising that current research is showing that maternal mental illness has unique neural profiles. Furthermore, the neural systems affected by peripartum mental illness overlap and interact with the systems involved in maternal caregiving behaviors, and mother-infant interactions are, therefore, highly susceptible to disruption. This review discusses what we know about the unique neural changes occurring during peripartum mental illness and the role of the hypothalamus in these illnesses. With an improved understanding of the neural correlates of maternal mental health and disease, we will be better equipped to predict risk, develop effective treatments, and ultimately prevent suffering for millions of parents during this critical time in life.

Neurobiological changes during the peripartum period: implications for health and behavior

Pregnancy and the transition to parenthood is an important period marked by dramatic neurobiological and psychosocial changes that may have implications for the health of women and offspring. Although human and non-human animal research suggests that the brain undergoes alterations during the peripartum period, these changes are poorly understood. Here, we review existing research, particularly human neuroimaging and psychophysiological research, to examine changes in brain structure and function during the peripartum period and discuss potential implications for the health of women and offspring. First, we discuss the potential causes of these changes across pregnancy, including physiological and psychosocial factors. Next, we discuss the evidence for structural and functional changes in the brain during pregnancy and into the postpartum period, noting the need for research conducted prospectively across human pregnancy. Finally, we propose potential models of individual differences in peripartum neurobiological changes (i.e. hypo-response, typical response, hyper-response) and emphasize the need to consider trajectories of change in addition to pre-existing factors that may predict maternal adjustment to parenthood. We suggest that the consideration of individual differences in neurobiological trajectories across pregnancy may contribute to a better understanding of risk for negative health and behavior outcomes for women and offspring.

Biological stress response in women at risk of postpartum psychosis: The role of life events and inflammation

BACKGROUND

Postpartum psychosis (PP) is the most severe psychiatric disorder associated with childbirth, and the risk is particularly high in women with a history of bipolar disorder, schizoaffective disorder or in those who have suffered previous episodes of PP. While studies in patients with psychosis not related to the puerperium have demonstrated that abnormalities in stress response are important risk factors for psychosis, it remains unknown whether this is also the case for PP.

METHODS

This study includes 30 postpartum women, assessed, on average, at postpartum week 14.8 ± 10.1 either with a current episode of PP (n = 14), or at-risk of PP because of a history of bipolar/schizoaffective disorder but who were well (n = 16), and a group of healthy women (n = 26). Details about recent stressful life events were obtained using the List of Threatening Experiences questionnaire, while perceived stress was evaluated using the Perceived Stress Scale. We estimated hypothalamic-pituitary adrenal (HPA) activity by measuring salivary cortisol at awakening; at 15, 30, and 60 min after awakening; at noon; and at 8 pm. An Area Under the Curve analysis was performed to assess the awakening response (AUCi) and cortisol levels during the day (AUCg). Immune markers, including high sensitivity C-Reactive Protein (hs-CRP) and Interleukin (IL)-1a, IL-1b, IL-2, IL-4, IL-6, IL-8, IL-10, Tumor Necrosis Factor (TNFa), Vascular Endothelial Growth Factor (VEGF), Interferon gamma (INFγ), Monocyte Chemoattractant Protein 1 (MCP-1), and Epidermal Growth Factor (EGF) were evaluated from peripheral blood samples.

RESULTS

Women with current PP reported more frequent recent stressful life events, and higher perceived stress than healthy women. They also showed an activation of the stress and immune response, with higher levels of cortisol AUCg and hs-CRP (but not of other inflammatory markers) than healthy controls. Women at-risk of PP who remained well had values on these measures that were intermediate between those of women with a current episode of PP and those of healthy women. Stress measures and markers of stress and immune response explained 78 % of the variance of in group status between PP and healthy women, and 46 % of variance of in group status between women at-risk and healthy women.

CONCLUSION

These findings suggest that an immune-HPA axis dysregulation, together with current stress may represent an important underlying pathophysiological mechanism in the onset of psychosis after childbirth in vulnerable women.

Neurobiology of maternal mental illness

This chapter provides an overview of current research discoveries beginning to uncover the neurobiology of maternal mental illness. Results are described according to standard diagnostic categories (specifically, perinatal depression, perinatal anxiety and OCD, postpartum psychosis and bipolar disorder, and trauma and posttraumatic stress disorder), yet we aim to put this approach in context with the introduction of a classification model for psychiatric research, the research domain criteria, gaining traction in basic and clinical translational fields. We first review a new area of study, the neuroplasticity of the pregnant and postpartum brain, as work here has relevance for understanding the pathophysiology of mental disorders and may provide clues to changes in brain functioning that are related to compromised parenting in the context of postpartum depression. We next provide background information on neuroendocrine and immune changes during pregnancy and, to a lesser extent, the postpartum period, as alterations in these systems are significantly implicated in underlying neurobiology of mental illness for peripartum women. Our discussion of the major mental illnesses for pregnant and postpartum women includes neuroendocrine changes, neuroinflammation, and neurotransmitter alterations, as well as circuit dysfunction. Overall, remarkable progress has been made in identifying variations in neurobiology (and related systems) involved in maternal mental illness; yet, it is clear that, as classified with standard diagnostic systems, these are heterogeneous disorders and there is individual variability in the alterations in neurobiology for the same illness.

An Analysis of Cellular Communication Network Factor Proteins as Candidate Mediators of Postpartum Psychosis Risk

Postpartum (or puerperal) psychosis (PP) is a severe psychiatric condition associated with hallucinations, delusions, cognitive disorganization, and mood problems, which affects approximately 1-2 out of every 1,000 mothers shortly after childbirth. While the risk factors for, and co-morbidities of, PP are relatively well-defined, currently, the pathophysiology underlying the disorder is very poorly-specified. Here, I argue, on the basis of multiple lines of new evidence, that altered expression of the Cellular Communication Network (CCN) factor proteins (and of the heterodimerizing CCN2 and CCN3 proteins in particular), may be associated with, and possibly causal for, increased PP risk. Future preclinical and clinical studies should aim to test this hypothesis as empirical support for it would provide much-needed clues regarding the biological substrates of PP, and could point to predictive biomarkers for the condition.

Brain plasticity in pregnancy and the postpartum period: links to maternal caregiving and mental health

Pregnancy and the postpartum period involve numerous physiological adaptations that enable the development and survival of the offspring. A distinct neural plasticity characterizes the female brain during this period, and dynamic structural and functional changes take place that accompany fundamental behavioral adaptations, stimulating the female to progress from an individual with self-directed needs to being responsible for the care of another life. While many animal studies detail these modifications, an emerging body of research reveals the existence of reproduction-related brain plasticity in human mothers too. Additionally, associations with aspects of maternal caregiving point to adaptive changes that benefit a woman's transition to motherhood. However, the dynamic changes that affect a woman's brain are not merely adaptive, and they likely confer a vulnerability for the development of mental disorders. Here, we review the changes in brain structure and function that a woman undergoes during the peripartum period, outlining associations between these neural alterations and different aspects of maternal care. We additionally discuss peripartum mood disorders and postpartum psychosis, and review the neuroimaging studies that investigate the neural bases of these conditions.

Development of Neuroimaging-Based Biomarkers in Psychiatry

This chapter presents an overview of accumulating neuroimaging data with emphasis on translational potential. The subject will be described in the context of three disease states, i.e., schizophrenia, bipolar disorder, and major depressive disorder, and for three clinical goals, i.e., disease risk assessment, subtyping, and treatment decision.

Do Defective Immune System-Mediated Myelination Processes Increase Postpartum Psychosis Risk?

Postpartum (or puerperal) psychosis (PP) is a rare, severe psychiatric disorder that affects women shortly after childbirth; risk is particularly high in individuals with a history of bipolar disorder or PP, but the underlying pathophysiology remains poorly understood. Emerging evidence suggests that immune system (dys)function plays an important role in disorder onset. On the basis of new findings from clinical and animal model studies, we hypothesise that the abundance and/or activity of regulatory T cells, and the efficacy of consequent (re)myelination processes in the brain mediated by CCN proteins, is perturbed in PP; this pathway may be modulated by risk and protective/treatment factors for the disorder, and identifying abnormalities within it could signpost novel predictive biomarkers and therapeutic targets.