Infant Neurodevelopment is Affected by Prenatal Maternal Stress: The QF2011 Queensland Flood Study

Prenatal stress impacts foetal neurodevelopment: Temporal windows of gestational vulnerability

Prenatal maternal stressors ranging in severity from everyday occurrences/hassles to the experience of traumatic events negatively impact neurodevelopment, increasing the risk for the onset of psychopathology in the offspring. Notably, the timing of prenatal stress exposure plays a critical role in determining the nature and severity of subsequent neurodevelopmental outcomes. In this review, we evaluate the empirical evidence regarding temporal windows of heightened vulnerability to prenatal stress with respect to motor, cognitive, language, and behavioural development in both human and animal studies. We also explore potential temporal windows whereby several mechanisms may mediate prenatal stress-induced neurodevelopmental effects, namely, excessive hypothalamic-pituitary-adrenal axis activity, altered serotonin signalling and sympathetic-adrenal-medullary system, changes in placental function, immune system dysregulation, and alterations of the gut microbiota. While broadly defined developmental windows are apparent for specific psychopathological outcomes, inconsistencies arise when more complex cognitive and behavioural outcomes are considered. Novel approaches to track molecular markers reflective of the underlying aetiologies throughout gestation to identify tractable biomolecular signatures corresponding to critical vulnerability periods are urgently required.

Climate Change is an Emerging Threat to Perinatal Mental Health

OBJECTIVE

In this discussion, we build the case for why climate change is an emerging threat to perinatal mental health.

METHOD

A search of current literature on perinatal and maternal mental health and extreme weather events was conducted in PubMed/MEDLINE and Web of Science databases. Only articles focusing on maternal mental health were included in this narrative review.

RESULTS

The perinatal period represents a potentially challenging timeframe for women for several reasons. Necessary role adjustments (reprioritization), changes in one's ability to access pre-birth levels (and types) of social support, fluctuating hormones, changes in body shape, and possible complications during pregnancy, childbirth, or postpartum are just a few of the factors that can impact perinatal mental health. Trauma is also a risk factor for negative mood symptoms and can be experienced as the result of many different types of events, including exposure to extreme weather/natural disasters.

CONCLUSION

While the concepts of "eco-anxiety," "climate despair," and "climate anxiety" have garnered attention in the mainstream media, there is little to no discussion of how the climate crisis impacts maternal mental health. This is an important omission as the mother's mental health impacts the family unit as a whole.

Prenatal anxiety during the pandemic context is related to neurodevelopment of 6-month-old babies

Prenatal anxiety and depression in pandemic context could introduce changes in the fetal developmental trajectories that, ultimately, could alter the adaptive behaviors of the offspring, potentially affecting, for example, general neurodevelopment. The sample consisted of 105 mother-child dyads, recruited between March and May 2020. The dyads were evaluated longitudinally, prenatally and postnatally (6 months). The Pandemic Impact Questionnaire, the State-Trait Anxiety Inventory, and the Beck-II Depression Inventory were used to assess indicators of maternal anxiety and depression, respectively. Regarding the babies, their mothers responded to Age and Stages: 3, which assesses different dimensions of early neurodevelopment, in addition to a closed questionnaire to identify sociodemographic and maternal and child health variables. A series of mediation models were tested to examine the association between prenatal psychopathology/negative experiences of the pandemic and neurodevelopment. The results indicated that the negative experiences of the pandemic were indirectly associated with the socio-individual and fine motor neurodevelopment of the offspring, through maternal anxiety symptoms, during the third trimester, which functioned as a mediator.  Conclusions: This study provides evidence on the mediating effects of maternal anxiety on infant neurodevelopment in contexts of early adversity. It is important to point out the need to implement public health policies that allow a timely evaluation of neurodevelopmental variables during early childhood, which can implement early interventions to reduce the risks associated with these deficits. What is Known: • Effects of maternal mental health have been reported, effects on child neurodevelopment, in motor, cognitive, linguistic and socio-emotional dimensions. • Contexts of early adversity have been associated with maternal mental health and offspring development. What is New: • The context of pandemic adversity caused by COVID-19 is associated with motor and socio-individual neurodevelopment, mediated by maternal prenatal anxiety.

Differences in infant negative affectivity during the COVID-19 pandemic

This longitudinal study compared infant temperament rated at 3 months postpartum by 263 United-States-based women who gave birth during the COVID-19 pandemic and 72 who gave birth prior to the pandemic. All women completed questionnaires assessing perinatal mental health, social contact, and infant temperament. Mothers whose infants were born during the pandemic reported higher levels of infant negative affectivity as compared with mothers whose infants were born earlier (F(1, 324) = 18.28, p < .001), but did not differ in their ratings of surgency or effortful control. Maternal prenatal depressive symptoms, prenatal stress, and postpartum stress mediated differences in infant negative affectivity  between pandemic and pre-pandemic groups. Within the pandemic group, decreased postpartum social contact was associated with higher ratings of infant negative affectivity. These findings suggest that the pandemic has affected maternal perceptions of infant temperament, perinatal mental health, and social contact.

Association between prenatal maternal anxiety and/or stress and offspring's cognitive functioning: A meta-analysis

This meta-analysis examined the relationship between prenatal maternal stress and/or anxiety and the outcomes of children aged 3 months to 9 years. Of the 8754 studies published before June 2021 that were synthesized, 17 conducted in Western countries were included in the meta-analysis (Ntotal  = 23,307; Mmales 54%; Methnicity White 77%, Pacific 15%, African American/Black 10%, Middle Eastern 7%, Eastern 8%). Effect sizes ranged from -0.41 to 0.15. A weak negative association was found between prenatal stress and/or anxiety exposure and children's general intellectual development. Associations varied based on the type of exposure. Findings are limited to developed counties and cannot be generalized to low- and middle-income countries. Directions for maternal prenatal intervention and future studies are discussed.

Urinary 1H NMR Metabolomic Analysis of Prenatal Maternal Stress Due to a Natural Disaster Reveals Metabolic Risk Factors for Non-Communicable Diseases: The QF2011 Queensland Flood Study

Prenatal stress alters fetal programming, potentially predisposing the ensuing offspring to long-term adverse health outcomes. To gain insight into environmental influences on fetal development, this QF2011 study evaluated the urinary metabolomes of 4-year-old children (n = 89) who were exposed to the 2011 Queensland flood in utero. Proton nuclear magnetic resonance spectroscopy was used to analyze urinary metabolic fingerprints based on maternal levels of objective hardship and subjective distress resulting from the natural disaster. In both males and females, differences were observed between high and low levels of maternal objective hardship and maternal subjective distress groups. Greater prenatal stress exposure was associated with alterations in metabolites associated with protein synthesis, energy metabolism, and carbohydrate metabolism. These alterations suggest profound changes in oxidative and antioxidative pathways that may indicate a higher risk for chronic non-communicable diseases such obesity, insulin resistance, and diabetes, as well as mental illnesses, including depression and schizophrenia. Thus, prenatal stress-associated metabolic biomarkers may provide early predictors of lifetime health trajectories, and potentially serve as prognostic markers for therapeutic strategies in mitigating adverse health outcomes.

Prenatal maternal stress during the COVID-19 pandemic and infant regulatory capacity at 3 months: A longitudinal study

The COVID-19 pandemic is a global traumatic experience for citizens, especially during sensitive time windows of heightened plasticity such as pregnancy and neonatal life. Pandemic-related stress experienced by mothers during pregnancy may act as an early risk factor for infants' regulatory capacity development by altering maternal psychosocial well-being (e.g., increased anxiety, reduced social support) and caregiving environment (e.g., greater parenting stress, impaired mother-infant bonding). The aim of the present longitudinal study was to assess the consequences of pandemic-related prenatal stress on infants' regulatory capacity. A sample of 163 mother-infant dyads was enrolled at eight maternity units in northern Italy. They provided complete data about prenatal stress, perceived social support, postnatal anxiety symptoms, parenting stress, mother-infant bonding, and infants' regulatory capacity at 3 months of age. Women who experienced emotional stress and received partial social support during pregnancy reported higher anxious symptoms. Moreover, maternal postnatal anxiety was indirectly linked to the infants' regulatory capacity at 3 months, mediated by parenting stress and mother-infant bonding. Dedicated preventive interventions should be delivered to mothers and should be focused on protecting the mother-infant dyad from the detrimental effects of pandemic-related stress during the COVID-19 healthcare emergency.

Maternal Distress during Pregnancy and the Postpartum Period: Underlying Mechanisms and Child's Developmental Outcomes-A Narrative Review

Maternal mental health may be considered a determining factor influencing fetal and child development. An essential factor with potentially negative consequences for a child's psychophysiological development is the presence of maternal distress during pregnancy and the postpartum period. The review is organized and presented to explore and describe the effects of anxiety, stress, and depression in pregnancy and the postpartum period on adverse child developmental outcomes. The neurobiology of maternal distress and the transmission mechanisms at the molecular level to the fetus and child are noted. In addition, the paper discusses the findings of longitudinal studies in which early child development is monitored concerning the presence of maternal distress in pregnancy and the postpartum period. This topic gained importance in the COVID-19 pandemic context, during which a higher frequency of maternal psychological disorders was observed. The need for further interdisciplinary research on the relationship between maternal mental health and fetal/child development was highlighted, especially on the biological mechanisms underlying the transmission of maternal distress to the (unborn) child, to achieve positive developmental outcomes and improve maternal and child well-being.

NICU-based stress response and preterm infant neurobehavior: exploring the critical windows for exposure

BACKGROUND

Exposure to maternal stress in utero negatively impacts cognitive and behavioral outcomes of children born at term. The neonatal intensive care unit (NICU) can be stressful for preterm infants during a developmental period corresponding to the third trimester of gestation. It is unknown whether stress in the NICU contributes to adverse neurodevelopment among NICU graduates. The aim was to examine the association between salivary cortisol and early neurodevelopment in preterm infants.

METHODS

We examined the association between cortisol levels during the NICU hospitalization and subsequent performance on the NICU Network Neurobehavioral Scales (NNNS), estimating time-specific associations and considering sex differences.

RESULTS

Eight hundred and forty salivary cortisol levels were measured from 139 infants. Average cortisol levels were inversely associated with NNNS Regulation scores for both male and female infants (β = -0.19; 95% CI: -0.44, -0.02). Critical developmental windows based on postmenstrual age were identified, with cortisol measured <30 weeks PMA positively associated with Habituation and Lethargy scores (β = 0.63-1.04). Critical developmental windows based on chronological age were identified, with cortisol measured in the first week of life inversely associated with Attention score (β = -1.01 for females; -0.93 for males).

CONCLUSIONS

Stress in the NICU at specific developmental time points may impact early preterm infant neurodevelopment.

IMPACT

Stress in the neonatal intensive care unit can impact the neurodevelopmental trajectory of premature infants. The impact of stress is different at different points in development. The impact of stress is sexually dimorphic.

Effects of Maternal and Child Lifetime Traumatic Stress Exposures, Infant Temperament, and Caregiving Quality on Preschoolers' Executive Functioning

We examined effects of maternal and child lifetime traumatic stress exposures, infant temperament, and caregiving quality on parent ratings of preschoolers' executive functioning (EF). Maternal lifetime trauma was associated with preschoolers' EF problems; this association was mediated by greater child trauma exposure. Infant temperament was associated with EF abilities, particularly among females. Among males, infant extraversion/surgency mediated the association of maternal lifetime trauma with poorer child EF. Caregiving quality was negatively associated with maternal and child trauma exposures but did not predict child EF. Findings have implications for interventions to identify children at risk for poor EF and optimize outcomes.

Elemental analysis of hair provides biomarkers of maternal hardship linked to adverse behavioural outcomes in 4-year-old children: The QF2011 Queensland Flood Study

BACKGROUND

Exposure to adverse experiences during pregnancy, such as a natural disaster, can modify development of the child with potential long-term consequences. Elemental hair analysis may provide useful indicators of cellular homeostasis and child health. The present study investigated (1) if flood-induced prenatal maternal stress is associated with altered hair elemental profiles in 4-year-old children, and (2) if hair elemental profiles are associated with behavioural outcomes in children.

METHODS

Participants were 75 children (39 boys; 36 girls) whose mothers were exposed to varying levels of stress due to a natural disaster (2011 Queensland Flood, Australia) during pregnancy. At 4 years of age, language development, attention and internalizing and externalizing problems were assessed and scalp hair was collected. Hair was analyzed by inductively coupled plasma mass spectrometry (ICP-MS) for 28 chemical elements.

RESULTS

A significant curvilinear association was found between maternal objective hardship and copper levels in boys, as low and high maternal objective hardship levels were associated with the highest hair copper levels. Mediation analysis revealed that low levels of maternal objective hardship and high levels of copper were associated with lower vocabulary scores. Higher levels of maternal objective hardship were associated with higher magnesium levels, which in turn were associated with attention problems and aggression in boys. In girls, high and low maternal objective hardship levels were associated with high calcium/potassium ratios.

CONCLUSION

Elemental hair analysis may provide a sensitive biomonitoring tool for early identification of health risks in vulnerable children.

New Life Through Disaster: A Thematic Analysis of Women's Experiences of Pregnancy and the 2016 Fort McMurray Wildfire

Background

On May 3, 2016, residents of Fort McMurray Wood Buffalo, Alberta were evacuated due to an uncontrolled wildfire. The short-notice evacuation had destabilizing consequences for residents, including changes in routines, loss of control, and increased uncertainty. These consequences were especially detrimental to women who were pregnant or pre-conception during the evacuation. Pregnant and pre-conception women are particularly susceptible to a vast range of negative consequences during and post natural disasters, including elevated stress and higher incidence of pregnancy complications including gestational diabetes mellitus, pregnancy induced hypertension and C-section. The aim of this study was to understand the experiences, perceived stress and resilience of women who were pregnant during the wildfire. As well as to explore potential interventions to promote the health and enhance resilience of pregnant women and to assist in recovery after exposure to a natural disaster or other traumatic events.

Methods

A qualitative thematic analysis of 16 narratives penned by pregnant women and recounted in Ashley Tobin's compilations 93/88,000 and 159 More/ 88,000: Stories of Evacuation, Re-Entry and the In-Between was conducted.

Results

Analysis revealed five key themes: (1) experience of stress responses due to personal and external factors, (2) social connectedness and support as a facilitator of resilience, (3) performance of resilience-enhancing activities, (4) the roles of pregnancy and motherhood in the experiences of loss and resilience, and (5) the importance of home.

Conclusion

Pregnant women have unique barriers that may negatively impact them during a natural disaster or other form of stressful event. They may benefit from assistance with navigating role transition during pregnancy, training in stress management strategies, and writing interventions to build resiliency and begin the process of recovery from trauma.

The COVID-19 infection in children and its association with the immune system, prenatal stress, and neurological complications

The Coronavirus disease 2019 (COVID-19)" caused by the "severe acute respiratory syndrome corona virus 2 (SARS-CoV-2)" has caused huge losses to the world due to the unavailability of effective treatment options. It is now a serious threat to humans as it causes severe respiratory disease, neurological complications, and other associated problems. Although COVID-19 generally causes mild and recoverable symptoms in children, it can cause serious severe symptoms and death causing complications. Most importantly, SARS-CoV-2 can cause neurological complications in children, such as shortness of breath, myalgia, stroke, and encephalopathy. These problems are highly linked with cytokine storm and proinflammatory responses, which can alter the physiology of the blood-brain barrier and allow the virus to enter the brain. Despite the direct infection caused by the virus entry into the brain, these neurological complications can result from indirect means such as severe immune responses. This review discusses viral transmission, transport to the brain, the associated prenatal stress, and neurological and/or immunological complications in children.

Effect of Natural Disaster-Related Prenatal Maternal Stress on Child Development and Health: A Meta-Analytic Review

The evidence supporting the idea that natural disaster-related prenatal maternal stress (PNMS) influences the child’s development has been accumulating for several years. We conducted a meta-analytical review to quantify this effect on different spheres of child development: birth outcomes, cognitive, motor, physical, socio-emotional, and behavioral development. We systematically searched the literature for articles on this topic (2756 articles retrieved and 37 articles included in the systematic review), extracted the relevant data to calculate the effect sizes, and then performed a meta-analysis for each category of outcomes (30 articles included across the meta-analyses) and meta-regressions to determine the effect of some factors of interest on the association between PNMS and child development: type of PNMS (objective, psychological, cognitive, diet), type of natural disaster (ice storm, flood/cyclone), type of report (maternal, third-party observer, medical), timing of exposure (preconception exposure included or not) and child age at assessment (under 10 or 10 years and older). We found that PNMS significantly influences all spheres of child development. Higher PNMS levels were associated with longer gestational age, larger newborns, and higher BMI and adiposity levels, as well as worse cognitive, motor, socio-emotional, and behavioral outcomes.

The Fort McMurray Mommy Baby Study: A Protocol to Reduce Maternal Stress Due to the 2016 Fort McMurray Wood Buffalo, Alberta, Canada Wildfire

Introduction: Data show that maternal stress triggered by exposure to a natural disaster before, during or just after pregnancy is associated with adverse pregnancy and newborn outcomes. In this paper, the first aim is to describe our efforts to test a simple, low-cost intervention to large numbers of women following a major natural disaster. The second aim is to outline the challenges faced and lessons learned during the execution of this natural disaster study. Methods: The setting was the May 2016 Fort McMurray Wood Buffalo wildfire in northern Alberta, Canada. Women who were pregnant or preconception at the time of the disaster were invited to participate via social media. This prospective cohort study included a randomized controlled trial to test the effectiveness of an expressive writing intervention on the levels of prenatal maternal stress and maternal, birth, and early childhood outcomes. At recruitment and at multiple timepoints postpartum, a battery of questionnaires was administered to evaluate objective and subjective stress exposure to the fire as well as maternal mental health, resilience and its contributing factors as well as infant developmental milestones. Qualitative content analysis of the expressive writing was conducted. Discussion: There is an increasing need to develop effective, wide-spread, rapid, and low-cost interventions to reduce prenatal maternal stress, increase resilience, and improve pregnancy outcomes following a natural disaster. Though analysis of data is ongoing, we highlight the strengths of this study which include strong community participation, rapid recruitment of eligible participants, low-cost intervention and data acquisition, and successful testing of the intervention. We acknowledge the challenges we encountered including the high rate of participant disqualifications or losses due to incomplete collection of online data; evacuation, dispersal, and inconsistent return to homes; and the high levels of stress accumulated post-disaster which led to inability to complete the study. Despite potential challenges, there remains a need for such research amid natural disasters.

Identifying a biological signature of prenatal maternal stress

Psychological stress affects maternal gastrointestinal (GI) permeability, leading to low-grade inflammation, which can negatively affect fetal development. We investigated a panel of circulating markers as a biological signature of this stress exposure in pregnant women with and without the stress-related GI disorder irritable bowel syndrome (IBS). Markers of GI permeability and inflammation were measured in plasma from healthy and IBS cohorts of women at 15 and 20 weeks’ gestation. Biomarkers were evaluated with respect to their degree of association to levels of stress, anxiety, and depression as indicated by responses from the Perceived Stress Scale, State-Trait Anxiety Inventory, and Edinburgh Postnatal Depression Scale. High levels of stress were associated with elevations of soluble CD14, lipopolysaccharide binding protein (LBP), and tumor necrosis factor–α, while anxiety was associated with elevated concentrations of C-reactive protein (CRP) in otherwise healthy pregnancies. Prenatal depression was associated with higher levels of soluble CD14, LBP, and CRP in the healthy cohort. High levels of prenatal anxiety and depression were also associated with lower concentrations of tryptophan and kynurenine, respectively, in the IBS cohort. These markers may represent a core maternal biological signature of active prenatal stress, which can be used to inform intervention strategies via stress reduction techniques or other lifestyle approaches. Such interventions may need to be tailored to reflect underlying GI conditions, such as IBS.

Coping During Pregnancy Following Exposure to a Natural Disaster: The QF2011 Queensland Flood Study

INTRODUCTION

This study investigated how coping strategies moderated the impact of disaster-related objective hardship on subjective distress in pregnant women.

METHODS

The objective hardship (exposure severity), subjective distress (Peritraumatic Distress Inventory, Peritraumatic Dissociative Experiences Questionnaire and Impact of Event Scale-Revised) and coping styles (Brief COPE) of pregnant women (N = 226) exposed to the 2011 Queensland, Australia flood were assessed. Moderation analyses were used to assess how coping strategies moderated the relationship between objective hardship and subjective distress levels.

RESULTS

We found that the more severe the objective flood exposure, the greater the women's subjective distress. The moderation analyses were significant for the Brief COPE's three coping styles (i.e., problem-focused coping, emotion-focused coping, and dysfunctional coping). For women experiencing high levels of objective hardship, problem-focused (∆R² = 1.7%) and dysfunctional coping (∆R² = 1.5%) elevated subjective distress levels. For women experiencing low or moderate levels of objective hardship, emotion-focused coping reduced levels of subjective distress (∆R² = 1.3%). A three-way interaction between objective hardship, emotion-focused coping, and dysfunctional coping approached significance (∆R² = 1.0%), indicating a protective role of emotion-focused coping under high levels of objective hardship, for women who frequently use maladaptive coping strategies.

LIMITATIONS

Sample was generally high SES and no measure of social support was available.

CONCLUSION

Results suggest that both problem-focused and dysfunctional coping strategies were maladaptive for women with relatively high exposure levels. Overall, emotion-focused coping strategies were more likely than problem-focused or dysfunctional strategies to reduce pregnant women's subjective distress following the flood.

Maternal stress in the first 1000 days and risk of childhood obesity: a systematic review

Objective: Maternal stress is associated with adverse child outcomes. Conception to 2-years postpartum (the first 1000 days) is a developmentally sensitive period for stress exposure. The role of maternal stress in the first 1000 days on child obesity risk is unclear. This review systematically examines the relationship between maternal stress across the first 1000 days and child obesity risk. Methods: The Cochrane Library, MEDLINE, PsycINFO, EMBASE, CINAHL, and Maternity and Infant Care were searched from inception to June 2018. Eligible studies included women who experienced maternal stress in the first 1000 days; an included a measure of maternal stress and of child anthropometrics. Results: Sixteen studies met inclusion criteria, the majority of these examined prenatal stress exposure. Inconsistent effects were observed for psychological and physiological stress responses, on child weight outcomes. Environmental stress exposures, including natural disaster and bereavement, were more consistently associated with increased obesity risk. Conclusion: This review does not provide support for the effects of psychological or physiological maternal stress on child weight outcomes; there is some evidence of associations between environmental stress exposures and greater childhood adiposity. Variation in conceptualisation and measurement of stress, timing of stress exposure, and limited examination of stress-related behaviours were noted.

A cross-lagged panel analysis of children's sleep, attention, and mood in a prenatally stressed cohort: The QF2011 Queensland flood study

BACKGROUND

It is well recognized that childhood sleep, attention and mood problems increase risk for multiple adverse outcomes across the life-span; therefore, understanding factors, such as prenatal maternal stress, that underlie these types of childhood problems is critical for developing interventions that may optimize longer-term functioning. Our goal was to determine the association between disaster-related stress in pregnancy and young children's sleep, attention, and anxious/depressed symptoms.

METHODS

Soon after a major flood in Australia in 2011, we assessed various aspects of disaster-related prenatal maternal stress (PNMS) in women who had been pregnant at the time. Mothers rated several domains of their children's development with the Child Behavior Checklist (CBCL) at ages 2½ (n = 134) and 4 years (n = 118).

RESULTS

The primary finding was that more severe objective flood-related hardship in pregnancy predicted higher sleep problem scores at 2½ years, and that a negative maternal cognitive appraisal of the flood predicted lower attention problem scores at 2½ years. A cross-lagged panel analysis examined the association between children's sleep, attention, and anxious/depressed symptoms within and across ages. Results showed that these problems were likely to co-occur at each age, and that they were stable from 2½ to 4 years. Additionally, anxious/depressed scores at age 2½ predicted sleep problem scores at 4 years, all else being equal.

LIMITATIONS

Limitations of the study include a relatively small sample size and the children's outcome data relied on maternal report using the CBCL, rather than independent observation of the children's functioning, which may have introduced reporter bias.

CONCLUSIONS

These findings highlight the importance of early intervention for these childhood problems to optimize long-term mental health, particularly under conditions of prenatal stress.

Prenatal Maternal Distress: A Risk Factor for Child Anxiety?

The deleterious association between various types of prenatal maternal psychological distress (PNMS, anxiety, depression, psychological distress, stress) and childhood anxiety symptomatology (internalizing behaviors, anxiety symptoms) has been established using both retrospective and prospective longitudinal studies across varied demographic cohorts and throughout development. Yet, the existing literature cannot claim maternal distress during pregnancy to be a specific risk factor for anxiety symptomatology, as studies utilizing such observational designs are unable to adequately account for confounding of potential genetic factors and the postnatal environment. In this review, we examine studies that attempt to minimize such confounding and thus disentangle the unique intrauterine exposure effect of varying types of PNMS on childhood anxiety symptomatology. Such methodologies include paternal versus maternal comparison studies, sibling comparisons, prenatal cross-fostering designs and timing of exposure studies (including disaster studies). Of the identified studies, findings indicate that prenatal maternal distress is likely to constitute a risk factor for anxiety symptomatology, although more studies are needed to replicate current findings in order to determine whether there are clear differences in effects across specific types of PNMS and for specific subpopulations. We review the methodological limitations and strengths of the literature prior to exploring avenues of future research and implications for theory and clinical practice.

The role of prenatal maternal stress in the development of childhood anxiety symptomatology: The QF2011 Queensland Flood Study

It is possible that findings suggesting a link between prenatal maternal stress (PNMS) and anxiety symptoms in offspring are confounded by postnatal and/or shared mother-child heritability effects. Following exposure to a natural disaster, the Queensland Flood Study investigated the unique and additive effects of various types of disaster-related PNMS (objective hardship, cognitive appraisal, and subjective distress) on childhood anxiety symptomatology (internalizing and/or anxiety symptom measures). Timing of flood exposure during pregnancy and child sex were examined as potential moderators. After controlling for maternal psychosocial factors, greater objective hardship as a result of the floods was significantly associated with greater anxiety symptoms (N = 114) and marginally associated with greater internalizing behaviors (N = 115). Earlier timing of the flood in pregnancy was associated with greater anxiety symptoms. No such associations were found between any PNMS measure and teacher-rated child internalizing behaviors (N = 90). Sex and timing did not moderate associations. Our findings suggest that, in isolation, increased maternal hardship due to exposure to an independent stressor, during pregnancy, may have a programming effect on childhood anxiety symptoms.

Sex Differences in Vulnerability to Prenatal Stress: a Review of the Recent Literature

PURPOSE OF REVIEW

To evaluate the degree to which recent studies provide evidence that the effects of prenatal maternal stress (PNMS) on child health outcomes vary depending on the child's biological sex. In this review, we used a broad definition of stress, including negative life events, psychological stress, and established stress biomarkers. We identified 50 peer-reviewed articles (published January 2015-December 2017) meeting the inclusion criteria.

RECENT FINDINGS

Most articles (k = 35) found evidence of either sex-specific associations (significant in one sex but not the other) or significant PNMSxstress interactions for at least one child health outcome. Evidence for sex-dependent effects was strongest in the group of studies evaluating child neural/nervous system development and temperament as outcomes. There is sufficient evidence of sex-dependent associations to recommend that researchers always consider the potential role of child sex in PNMS programming studies and report descriptive statistics for study outcomes stratified by child biological sex.

Disaster in pregnancy: midwifery continuity positively impacts infant neurodevelopment, QF2011 study

BACKGROUND

Research shows that continuity of midwifery carer in pregnancy improves maternal and neonatal outcomes. This study examines whether midwifery group practice (MGP) care during pregnancy affects infant neurodevelopment at 6-months of age compared to women receiving standard hospital maternity care (SC) in the context of a natural disaster.

METHODS

This prospective cohort study included 115 women who were affected by a sudden-onset flood during pregnancy. They received one of two models of maternity care: MGP or SC. The women's flood-related objective stress, subjective reactions, and cognitive appraisal of the disaster were assessed at recruitment into the study. At 6-months postpartum they completed the Ages and Stages Questionnaire (ASQ-3) on their infants' communication, fine and gross motor, problem solving, and personal-social skills.

RESULTS

Greater maternal objective and subjective stress predicted worse infant outcomes. Even when controlling for maternal stress from the flood, infants of mothers who were in the MGP model of maternity care performed better than infants of mothers in SC on two of the five ASQ-3 domains (fine motor and problem solving) at 6-months of age. Furthermore, infants in the SC model were more likely to be identified as at risk for delayed development on these domains than infants in the MGP model of care.

CONCLUSIONS

Continuity of midwifery care has positive effects on infant neurodevelopment when mothers experience disaster-related stress in pregnancy, with significantly better outcomes on two developmental domains at 6 months compared to infants whose mothers received standard hospital care.

The Effects of Prenatal Maternal Stress on Early Temperament: The 2011 Queensland Flood Study

OBJECTIVE

This study examined the effects of disaster-related prenatal maternal stress on infant temperament and whether the sex of the infant or the timing of the stressor in pregnancy would moderate the effects.

METHODS

Mothers' objective experiences of a sudden-onset flood in Queensland, Australia, their subjective emotional reactions, and cognitive appraisal of the event were assessed. At 6 months postpartum, 121 mothers reported their infant's temperament on the 5 dimensions of the Short Temperament Scale for Infants.

RESULTS

When controlling for postnatal maternal factors, subjective prenatal maternal stress and cognitive appraisal of the disaster were associated with easier aspects of infant temperament. However, several interesting interactions emerged showing negative effects of the flood. With higher levels of objective hardship in pregnancy, boys (but not girls) received more irritable temperament ratings. When the flood occurred early in pregnancy, higher levels of objective hardship predicted more arrhythmic infant temperament. Finally, mothers whose emotional response to the flood exceeded the hardship they endured reported significantly more active-reactive infants.

CONCLUSION

Prenatal maternal stress from a natural disaster predicted more difficult temperament ratings that were moderated by infant sex, timing of the flood in gestation, and mother's emotional response to the disaster.