Sexually dimorphic and interactive effects of prenatal maternal cortisol and psychological distress on infant cortisol reactivity

Perinatal Predictors and Mediators of Attachment Patterns in Preschool Children: Exploration of Children's Contributions in Interactions with Mothers

Insecure and disorganized attachment patterns in children are linked to poor health outcomes over the lifespan. Attachment patterns may be predicted by variables that influence the quality of children's interactions with their primary caregivers/parents (usually mothers) such as prenatal and postnatal exposures and the children's own behaviours in interactions. The purposes of this exploratory study were to examine: (1) prenatal predictors of children's attachment patterns, and (2) postnatal mediators and moderators of associations between prenatal predictors and children's attachment patterns, with adjustment for relevant covariates. Mother-child dyads (n = 214) from the longitudinal Alberta Pregnancy Outcomes and Nutrition (APrON) cohort were studied using valid and reliable measures. Hayes' mediation analysis was employed to determine direct and indirect effects. Mothers' prenatal cortisol levels directly predicted disorganized (versus organized) child attachment in unadjusted models. Children's passivity (in adjusted models) and compulsivity (in unadjusted and adjusted models) in parent-child interactions mediated the pathway between mothers' prenatal cortisol levels and children's disorganized attachment patterns. Serial mediation analyses revealed that mothers' cortisol levels predicted their children's cortisol levels, which predicted children's compulsivity, and, ultimately, disorganized attachment in both unadjusted and adjusted models. No predictors were correlated with children's insecure (versus secure) attachment. This exploratory research suggests that prenatal exposure to mothers' cortisol levels and children's behavioural contributions to parent-child interaction quality should be considered in the genesis of children's attachment patterns, especially disorganization. Interventions focused on parent-child interactions could also focus on addressing children's behavioral contributions.

Sex Differences in Stress-Induced Cortisol Response Among Infants of Mothers Exposed to Childhood Adversity

BACKGROUND

Adverse childhood experiences (ACEs) increase risk for mental illness in women and their children, and dysregulation of the hypothalamic-pituitary-adrenal axis may play a role. The impact of ACEs on the hypothalamic-pituitary-adrenal axis may be strongest when ACEs occur prepubertally and in people who are exposed to abuse ACEs.

METHODS

To test this, we measured salivary cortisol in 96 mother-infant dyads while mothers were separated from their infants, who were experiencing a laboratory stressor. Mothers completed the Adverse Childhood Experiences Questionnaire; ACEs that occurred prepubertally (pACEs) were measured, and mother-infant dyads were grouped based on maternal pACE history as follows: no pACEs, ≥1 pACEs with abuse, or ≥1 pACEs but no abuse.

RESULTS

Mothers with ≥1 pACEs exhibited decreases in cortisol (relative to preinfant stressor), which differed significantly from the cortisol increase experienced by mothers with no pACEs, regardless of abuse presence (p = .001) or absence (p = .002). These pACE groups did not differ from one another (p = .929). Significant sex differences in infant cortisol were observed in infants of mothers with ≥1 pACEs (regardless of abuse) but not in infants of mothers with no pACEs. When mothers had experienced ≥1 pACEs, males showed decreases in cortisol in response to a stressor whereas females demonstrated increases, and males and females differed significantly when their mothers had ≥1 pACEs with (p = .025) and without (p = .032) abuse.

CONCLUSIONS

Regardless of maternal exposure to childhood abuse, in response to a stressor, pACEs were associated with lower cortisol response in mothers and sex differences in 6-month-old infants, with males showing a lower cortisol response than females.

Investigation of Hypothalamic Pituitary Adrenal Axis and Oxytocinergic System Changes in a Pragmatic Randomized Controlled Feasibility Trial of Acupuncture for Antenatal Depression

Background: Antenatal depression is common and associated with detrimental impacts on women and their families. Disrupted neuroendocrine functioning is reported in women experiencing perinatal mental health disturbances. Preliminary randomized controlled trial (RCT) evidence suggests acupuncture may provide a safe and effective adjunct treatment; however, underlying mechanisms of effect are unclear. We conducted an RCT examination of acupuncture for the management of antenatal depressive symptomologies, which included oxytocinergic and hypothalamic pituitary adrenal (HPA) axis system evaluations. This article reports postintervention changes to cortisol: dehydroepiandrosterone (DHEA) ratios, and oxytocin (OT) hormone concentrations. Methods: Fifty-seven women with Edinburgh Postnatal Depression Scale (EPDS) scores ≥13 were randomized to receive individually tailored depressed specific acupuncture, progressive muscle relaxation (PMR) attention comparator, or treatment as usual (TAU). Weekly 1-h sessions were conducted for 8 weeks (24-31 of pregnancy). Preintervention and postintervention saliva samples were collected. Results: Postintervention mean cortisol: DHEA ratio differences were not significantly predicted by group allocation (n = 46, p = 0.065). Two-group comparisons demonstrated cortisol: DHEA ratios were significantly increased and predicted by group allocation when acupuncture was compared to TAU (p = 0.039); however, not between acupuncture and PMR (p = 0.179), or PMR and TAU (p = 0.421). Postintervention OT concentrations were not significantly predicted by group allocation. Limitations: Small sample size and posthoc analysis Conclusion: Findings suggest positive regulation of the HPA axis may be an underlying mechanism by which acupuncture provided the significant improvements to antenatal depression, stress, and distress observed in this cohort. Trial Registration: Registered on March 19, 2015, with the Australian New Zealand Clinical Trials Registry (ACTRN12615000250538).

Maternal caregiving moderates the impact of antenatal maternal cortisol on infant stress regulation

BACKGROUND

Emerging evidence suggests that antenatal exposure to maternal stress signals affects the development of the infant stress response systems. Animal studies indicate that maternal sensitive caregiving can reverse some of these effects. However, the generalizability of these findings to humans is unknown. This study investigated the role of maternal caregiving in the association between multiple markers of maternal antenatal stress and infant stress regulation.

METHODS

The sample consisted of 94 mother-infant (N = 47 males, mean postnatal weeks = 12; SD = 1.84) dyads. Maternal levels of Interleukin-6, C-Reactive Protein (CRP), diurnal cortisol and alpha amylase, depressive and anxiety symptoms were assessed in late pregnancy (mean gestational age = 34.76; SD = 1.12), whereas postnatal symptomatology, caregiving, and infant cortisol response to the inoculation were evaluated at 3 months.

RESULTS

Hierarchical linear models (HLMs) showed a significant interaction between maternal antenatal cortisol, caregiving, and time on infant cortisol reactivity, while controlling for gender, maternal age, and postnatal depression. Specifically, higher levels of maternal antenatal cortisol were associated with greater cortisol response only among infants of less emotionally available mothers. All other markers of antenatal stress were not significantly associated with infant cortisol reactivity either independently or in interaction with maternal caregiving.

CONCLUSIONS

Albeit preliminary, results provide the first evidence in humans that maternal sensitive caregiving may eliminate the association between antenatal maternal cortisol and infant cortisol regulation.

Prenatal distress, access to services, and birth outcomes during the COVID-19 pandemic: Findings from a longitudinal study

BACKGROUND/AIMS

During the COVID-19 pandemic, pregnant people have experienced disruptions to prenatal care, as well elevated rates of mental health problems and distress. The current longitudinal study aims to understand how different forms of prenatal distress (mental health problems, COVID-19 stressful experiences, and access to prenatal services) impact infant birth outcomes during the pandemic.

METHODS

Participants were 265 pregnant individuals from Ontario, Canada. Maternal depression, pregnancy-related anxiety, COVID-related stressors (i.e., financial difficulties, social isolation), and disruptions to prenatal and health services were assessed during pregnancy. Delivery experiences and birth outcomes were assessed in the early postpartum period. Associations between pregnancy stressors and birth outcomes were assessed using path analyses.

RESULTS

Participants reported experiencing substantial changes to their prenatal care due to COVID-19; 23.0 % had prenatal appointments cancelled, 47.9 % had difficulty accessing prenatal classes, and 60.8 % reported changes to their birth plans. Results of path analyses showed a unique effect of pregnancy-related anxiety during the pandemic on lower birth weight, younger gestational age at birth, and more infant birth problems. Further, multi-group path analysis revealed these effects were more pronounced in male infants.

CONCLUSIONS

Findings demonstrate that pregnant individuals in Ontario, Canada have experienced considerable disruptions to services during pregnancy. In addition, pregnancy-related anxiety was uniquely linked to elevated risk for adverse birth outcomes, which more heavily impacted male infants. These findings underscore the need for additional mental health support and access to services for pregnant people and their infants, to reduce long-term adverse maternal and fetal health outcomes.

Rethinking minority stress: A social safety perspective on the health effects of stigma in sexually-diverse and gender-diverse populations

For over two decades, the minority stress model has guided research on the health of sexually-diverse individuals (those who are not exclusively heterosexual) and gender-diverse individuals (those whose gender identity/expression differs from their birth-assigned sex/gender). According to this model, the cumulative stress caused by stigma and social marginalization fosters stress-related health problems. Yet studies linking minority stress to physical health outcomes have yielded mixed results, suggesting that something is missing from our understanding of stigma and health. Social safety may be the missing piece. Social safety refers to reliable social connection, inclusion, and protection, which are core human needs that are imperiled by stigma. The absence of social safety is just as health-consequential for stigmatized individuals as the presence of minority stress, because the chronic threat-vigilance fostered by insufficient safety has negative long-term effects on cognitive, emotional, and immunological functioning, even when exposure to minority stress is low. We argue that insufficient social safety is a primary cause of stigma-related health disparities and a key target for intervention.

Age and sex differences in the cortisol stress reactivity and recovery among infants exposed to prenatal psychological distress

BACKGROUND

Altered hypothalamic-pituitary-adrenal axis (HPA) functioning is one of the potential mechanisms bridging exposure to maternal prenatal psychological distress (PPD) and later risk for offspring psychiatric illness. Research on infant cortisol stress reactivity, on scarcely studied recovery and their associations with maternal PPD is needed to clarify these mechanisms. Knowledge on sex differences in prospective settings is largely lacking. We aimed at filling these gaps by building upon our previous report showing that exposure to maternal prenatal depressive and anxiety symptoms associates with slower cortisol recovery among 10-week-old female infants.

METHODS

In all, 363, 205 and 263 infants at 10 weeks, six and 14 months of age from the FinnBrain Birth Cohort Study participated in a stress test comprising of venipuncture and nasopharynx sampling. Five saliva cortisol samples were collected during each visit to measure cortisol reactivity and recovery. PPD was assessed from maternal self-reports for depressive, anxiety and pregnancy-related anxiety symptoms at gestational weeks 14, 24 and 34.

RESULTS

An 11% enhanced recovery among 14-month-old females was associated with higher depressive and anxiety symptoms (95% CI=1-23%) and pregnancy-related anxiety symptoms (2-21%). No alterations in the female cortisol reactivity or male cortisol stress responses were observed.

CONCLUSIONS

The opposite directions in the associations between the PPD exposure and infant cortisol recovery among 10-week-old and 14-month-old females suggest sex- and age-dependent associations between HPA axis functioning and PPD exposure among healthy infants. Follow-up is needed to characterize the impact of this altered negative feedback mechanism on later health.

Prenatal exposure to maternal psychological distress and telomere length in childhood

Telomere length (TL) is a biological marker of cellular aging, and shorter TL in adulthood is associated with increased morbidity and mortality risk. It is likely that these differences in TL are established long before adulthood, and there is growing evidence that TL can reflect prenatal experiences. Although maternal prenatal distress predicts newborn TL, it is unknown whether the relation between prenatal exposure to maternal distress and child TL persists through childhood. The purpose of the current longitudinal, prospective study is to examine the relation between prenatal exposure to maternal distress (perceived stress, depressive symptoms, pregnancy-related anxiety) and TL in childhood. Participants included 102 children (54 girls) and their mothers. Mothers' distress was assessed five times during pregnancy, at 12 weeks postpartum, and at the time of child telomere measurement between 6 and 16 years of age. Maternal distress during pregnancy predicted shorter offspring TL in childhood, even after accounting for postnatal exposure to maternal distress and other covariates. These findings indicate that maternal mental health predicts offspring TL biology later in childhood than previously observed. This study bolsters claims that telomere biology is subject to fetal programming and highlights the importance of supporting maternal mental health during pregnancy.

Longitudinal prospective study examining the effects of the timing of prenatal stress on infant and child regulatory functioning: the Michigan Prenatal Stress Study protocol

INTRODUCTION

A considerable literature implicates prenatal stress as a critical determinant of poor psychological functioning in childhood and beyond. However, knowledge about whether the timing of prenatal stress differentially influences the development of child outcomes, including psychopathology, is virtually unknown. The primary aim of our study is to examine how the timing of prenatal stress differentially affects early childhood regulatory functioning as a marker of psychopathology. Our second aim is to examine the mediating effects of maternal physiological and psychological factors during pregnancy. Our third aim is to examine the moderating effects of postnatal factors on child regulatory functioning. Our project is the first longitudinal, prospective, multimethod study addressing these questions.

METHODS AND ANALYSIS

Our ongoing study recruits pregnant women, oversampled for intimate partner violence (a common event-based stressor allowing examination of timing effects), with data collection starting at pregnancy week 15 and concluding 4 years post partum. We aim to have n=335 mother-child dyads. We conduct a granular assessment of pregnancy stress (measured weekly by maternal report) in order to reveal sensitive periods during fetal life when stress particularly derails later functioning. Pattern-based statistical analyses will be used to identify subgroups of women who differ in the timing of their stress during pregnancy and then test whether these patterns of stress differentially predict early childhood self-regulatory outcomes.

ETHICS AND DISSEMINATION

Due to the high-risk nature of our sample, care is taken to ensure protection of their well-being, including a safety plan for suicidal ideation and a safety mechanism (exit button in the online weekly survey) to protect participant data privacy. This study was approved by Michigan State University Institutional Review Board. Dissemination will be handled by data sharing through National Institute of Child Health and Human Development Data and Specimen Hub (DASH), as well as through publishing the findings in journals spanning behavioural neuroendocrinology to clinical and developmental psychology.

Associations Among Parental Caregiving Quality, Cannabinoid Receptor 1 Expression-Based Polygenic Scores, and Infant-Parent Attachment: Evidence for Differential Genetic Susceptibility?

Attachment is a biological evolutionary system contributing to infant survival. When primary caregivers/parents are sensitive and responsive to their infants’ needs, infants develop a sense of security. Secure infant attachment has been linked to healthy brain and organ-system development. Belsky and colleagues proposed the term differential susceptibility to describe context-dependent associations between genetic variations and behavioral outcomes as a function of parenting environments. Variations in the Cannabinoid Receptor Gene 1 (CNR1) are associated with memory, mood, and reward and connote differential susceptibility to more and less optimal parental caregiving quality in predicting children’s behavioral problems.

Interactions of genetic variants and prenatal stress in relation to the risk for recurrent respiratory infections in children

Genetic variants may predispose children to recurrent respiratory infections (RRIs) but studies on genotype-environment interaction are rare. We hypothesized that the risk for RRIs is elevated in children with innate immune gene variants, and that prenatal exposure to maternal psychological distress further increases the risk. In a birth cohort, children with RRIs (n = 96) were identified by the age of 24 months and compared with the remaining cohort children (n = 894). The risk for RRIs in children with preselected genetic variants and the interaction between maternal distress during pregnancy and child genotype were assessed with logistic regression. The IL6 minor allele G was associated with elevated risk for RRIs (OR 1.55; 95% CI 1.14-2.12). Overall, there was no interaction between maternal psychological distress and child genotype. Exploratory analyses showed that, the association between the variant type of IL6 and the risk for RRIs was dependent on prenatal exposure to maternal psychological distress in males (OR 1.96; 95% CI 1.04-3.67). Our study didn't find genotype-environment interaction between prenatal maternal distress and child genotype. Exploratory analyses suggest sex differences in gene-environment interaction related to susceptibility to RRIs.

Maternal prenatal cortisol programs the infant hypothalamic-pituitary-adrenal axis

One of the key proposed agents of fetal programming is exposure to maternal glucocorticoids. Experimental animal studies provide evidence that prenatal exposure to elevated maternal glucocorticoids has consequences for hypothalamic-pituitary-adrenal (HPA) axis functioning in the offspring. There are very few direct tests of maternal glucocorticoids, such as cortisol, during human pregnancy and associations with infant cortisol reactivity. The current study examined the link between maternal prenatal cortisol trajectories and infant cortisol reactivity to the pain of inoculation in a sample of 152 mother-infant (47.4% girls) pairs. The results from the current study provide insight into fetal programming of the infant HPA axis, demonstrating that elevated prenatal maternal cortisol is associated with a larger infant cortisol response to challenge at both 6 and 12 months of age.

Sex differences in the associations between maternal prenatal distress and infant cortisol reactivity and recovery

Previous research suggests that maternal prenatal psychological distress (PPD) is related to altered cortisol reactivity in the exposed child. There are indications for the sex differences in vulnerability for prenatal adversities that depend on the exposure and child outcome. Still, it is not known whether the association between maternal PPD and infant cortisol stress response is moderated by sex. In addition, the recovery phase of the cortisol stress response has not been given as much attention as reactivity. Our aim was to study the sex differences in the associations between self-reported maternal prenatal depressive-, anxiety- and pregnancy-related anxiety symptoms through gestational weeks 14, 24 and 34 and the saliva cortisol reactivity to and recovery from the acute stress among 10-week-old infants. The study population comprised of 363 mother-infant pairs from the FinnBrain Birth Cohort Study. We found evidence for sex-dependent associations between PPD exposure and infant cortisol response. A less steep recovery slope (-10 % per one SD increase in PPD [95 % CI = -18 to -2 %] and -8 % [-16 to 0 %] depending on the exposure) and a possibly less steep reactivity slope (-14 % [95 % CI = -25 to 0 %] and -10 % [-21 to 3 %]) were associated with higher PPD exposure in females. Of the PPD measures, the strongly intercorrelated, and thus combined, depressive and anxiety symptom score provided the most robust prediction of infant cortisol recovery. Our results demonstrate sexually dimorphic alterations in the functioning of the infant hypothalamus-pituitary-adrenal axis and especially in the functioning of the negative feedback loop of the axis after prenatal PPD exposure among healthy babies.

Long-Term Associations Between Prenatal Maternal Cortisol and Child Neuroendocrine-Immune Regulation

BACKGROUND

Advancing understanding of the developmental origins of neuroendocrine-immune (NEI) functioning is key to elucidating the biological mechanisms involved in health and disease risk across the lifespan. This study examined whether prenatal maternal hypothalamic-pituitary-adrenal (HPA) activity moderates child NEI relations and explored the consistency of this moderating effect across gestation.

METHODS

Pregnant women participated in five prenatal study visits from 24 to 38 weeks gestation. At each visit, women provided a saliva sample. In a 5-year follow-up study, children (n_female = 25, n_male=20) provided four saliva samples and participated in behavioral assessments and challenge tasks. Prenatal maternal saliva samples were assayed for cortisol. Child saliva samples were assayed for cortisol and cytokines (IL-1β, IL-6, IL-8, TNFα) as indices of HPA and inflammatory activity. Multilevel mixed-effects models examined the moderation of child NEI relations by prenatal maternal cortisol.

RESULTS

Among males, average prenatal maternal cortisol did not moderate child NEI relations. Among females, average prenatal maternal cortisol moderated some child NEI relations with higher prenatal cortisol associated with more positive cortisol-cytokine relations at age five. When examined by gestational time point, there were more significant NEI moderation effects by maternal cortisol from later gestation (≥ 30 weeks) than earlier.

CONCLUSIONS

The findings suggest prenatal maternal HPA activity may moderate child NEI functioning. Additional research conducted with more heterogeneous and larger samples is needed to fully understand these relations. Furthering our knowledge of NEI development has important research and clinical implications, particularly for understanding and addressing conditions with inflammatory pathophysiologies, such as depression and cardiovascular disease.

The role of HPA-axis function during pregnancy in the intergenerational transmission of maternal adverse childhood experiences to child behavior problems

The current study aimed to understand the mediating and/or moderating role of prenatal hypothalamic-pituitary-adrenal (HPA) axis function in the association between maternal adverse childhood experiences (ACEs) and child internalizing and externalizing behavior problems at age 4. The influence of timing and child sex were also explored. Participants were 248 mother-child dyads enrolled in a prospective longitudinal cohort study (the Alberta Pregnancy Outcomes and Nutrition Study). Maternal ACEs were retrospectively assessed while maternal self-reported depression and diurnal salivary cortisol were assessed prospectively at 6-26 weeks gestation (T1) and 27-37 weeks gestation (T2). Maternal report of child internalizing and externalizing problems was assessed at 4 years (T3). Results revealed that there was a negative indirect association between maternal ACEs and child internalizing behavior via a higher maternal cortisol awakening response (CAR). Maternal diurnal cortisol slope moderated the association between maternal ACEs and child behavior problems. Some of these effects were dependent on child sex, such that higher ACEs and a flatter diurnal slope at T1 was associated with more internalizing behavior in female children and more externalizing behavior in male children. There were timing effects such that the mediating and moderating effects were strongest at T1.

Prenatal maternal distress associates with a blunted cortisol response in rhinovirus-positive infants

INTRODUCTION

Prenatal exposure to maternal psychological distress (PD) may have programming effects on the fetus/infant hypothalamic-pituitary-adrenal (HPA) axis and subsequently on the development of the fetus' immune function. Therefore, our aim was to study whether prenatal exposure to PD is related to early infant HPA axis reactivity in the context of a subclinical rhinovirus infection that challenges infants HPA axis postnatally.

METHODS

This study included 336 10-week-old infants from the nested case control Focus Cohort of the FinnBrain Birth Cohort Study. The outcome was infant HPA axis reactivity in a stress test. The acute stressor comprised of pediatric examination with venipuncture and nasal swabs for virus assessment. Saliva cortisol samples were collected at 5 time points: baseline, 0, 15, 25 and 35 min after the stressor. HPA axis reactivity was defined by the cumulative post-stressor cortisol concentration.

RESULTS

HPA axis reactivity was blunted in the PD/rhinovirus + group compared to the average of control/rhinovirus+, PD/rhinovirus-, and control/rhinovirus- groups (difference: 14.7 ln [nmol/L] × min, 95% confidence interval 3.8-25.6, p =  .008). HPA axis reactivity was significantly blunted only in boys with rhinovirus detected when separately tested for boys and girls (p =  .04).

CONCLUSION

Our finding of PD-exposed rhinovirus-positive infants having blunted cortisol secretion gives rise to a hypothesis that maternal PD during pregnancy influences infant HPA axis functioning and the functioning of the immune system. Future studies are needed to test whether this suppression of the HPA axis that co-occurs with rhinovirus infection associates with later disease development (e.g., asthma).

Parenting Interacts With Plasticity Genes in Predicting Behavioral Outcomes in Preschoolers

BACKGROUND

Public health and pediatric nurses typically focus on supporting parenting to reduce the likelihood of children's behavioral problems. Studies have identified interactions between early exposures to stress in caregiving and child genotype in predicting children's behavioral problems, such that certain genotypes connote greater differential susceptibility or plasticity to environmental stressors. We sought to uncover the interaction between observational measures of parent-child relationship quality and genotype in predicting early-onset behavioral problems in 24-month-olds, using prospective methods.

METHODS

We conducted a secondary analysis of data collected on a subsample of 176 women and their infants enrolled during pregnancy in the ongoing Alberta Pregnancy Outcomes and Nutrition (APrON) cohort study. Inclusion criteria required mothers to be ≥18 years of age, English speaking and ≤22 weeks gestational age at enrollment. Genetic data were obtained from blood leukocytes and buccal epithelial cell samples, collected from infants at three months of age. For each child, the presence of plasticity alleles was determined for BDNF, CNR1, DRD2/ANKK1, DRD4, DAT1, 5-HTTLPR, and MAOA and an overall index was calculated to summarize the number of plasticity alleles present. Observational assessments of parent-child relationship quality (sensitivity, controlling, and unresponsiveness) were conducted at six months of age. Children's internalizing (e.g., emotionally reactive, anxious/depressed, somatic complaint, withdrawn) and externalizing (e.g., aggression, inattention) behaviors were assessed at 24 months of age. After extracting genetic data, a maximum likelihood method for regressions was employed with Akaike Information Criterion (AIC) for model selection.

RESULTS

When parents were less responsive and children possessed more plasticity alleles, children were more likely to be emotionally reactive, anxious/depressed, report somatic complaints, and withdrawn, while when parents were less responsive and children possessed fewer plasticity alleles, children were less likely to display these internalizing behaviors, in a differentially susceptible manner. Furthermore, when parents were more responsive, and children possessed more plasticity alleles, children were less likely to display internalizing behaviors (P = 0.034). Similarly, children who possessed either the CNR1-A plasticity allele (P = 0.010) or DAT1 9-repeat plasticity allele (P = 0.036) and experienced more/less parental control displayed more/fewer externalizing problems, respectively, in a differentially susceptible manner.

CONCLUSIONS

The plasticity index score interacted with parental unresponsiveness in predicting anxiety and depressive behavioral problems in children, while individual genetic variants interacted with parental controlling behavior in predicting aggression and inattention in children, suggestive of differential susceptibility to caregiving. Especially in the context of nursing interventions designed to support childrearing and children's development, nurses need to be aware of the interactions between child genotype and parenting in understanding how well interventions will work in promoting optimal child behavior.

Beyond the HPA-axis: Exploring maternal prenatal influences on birth outcomes and stress reactivity

Accumulating evidence suggests that antenatal maternal stress is associated with altered behavioral and physiological outcomes in the offspring, however, whether this association is causal and the underlying biological mechanisms remain largely unknown. While the most studied mediator of maternal stress influences on the fetus has generally been cortisol, alternative novel markers of stress or inflammation warrant further consideration. The current investigation explored the influence of variations in self-reported symptoms of distress, stress hormones and inflammatory markers on infant birth outcomes and early stress regulation. The sample consisted of 104 pregnant women (mean gestational age = 34.76; SD = 1.12) and their healthy newborns. Maternal self-reported symptoms of depression and anxiety were evaluated through the Edinburgh Postnatal Depression Scale and the State-Trait Anxiety Inventory and levels of serum Interleukine-6 (IL-6), C-Reactive Protein (CRP), salivary cortisol and alpha amylase (sAA) were measured in late pregnancy. Newborns' cortisol and behavioral response to the heel-stick was assessed 48-72 hours after birth. The associations between maternal stress measures and infant birth outcomes and stress reactivity, adjusted for potential confounders, were examined through hierarchical linear regressions and hierarchical linear models. Higher maternal IL-6 levels were associated with smaller head circumference at birth, while diurnal sAA levels were positively associated with birthweight. Maternal diurnal cortisol was related to newborn's stress reactivity: a flatter infant cortisol response to the heel-stick was associated with greater maternal cortisol increases after awakening during pregnancy, while greater infant behavioural reactivity was related to a flatter maternal diurnal cortisol profile. The observational nature of these data does not allow for causal inferences but the current findings illustrate that antenatal factors related to alterations in maternal stress and immune response systems are associated with fetal growth and neonatal stress reactivity. This may have implications for later health and psychological outcomes.

Early gestational ethanol exposure in mice: Effects on brain structure, energy metabolism and adiposity in adult offspring

We examined whether an early-life event - ethanol exposure in the initial stages of pregnancy - affected offspring brain structure, energy metabolism, and body composition in later life. Consumption of 10% (v/v) ethanol by inbred C57BL/6J female mice from 0.5 to 8.5 days post coitum was used to model alcohol exposure during the first 3-4 weeks of gestation in humans, when pregnancy is not typically recognized. At adolescence (postnatal day [P] 28) and adulthood (P64), the brains of male offspring were scanned ex vivo using ultra-high field (16.4 T) magnetic resonance imaging and diffusion tensor imaging. Energy metabolism and body composition were measured in adulthood by indirect calorimetry and dual-energy X-ray absorptiometry (DXA), respectively. Ethanol exposure had no substantial impact on white matter organization in the anterior commissure, corpus callosum, hippocampal commissure, internal capsule, optic tract, or thalamus. Whole brain volume and the volumes of the neocortex, cerebellum, and caudate putamen were also unaffected. Subtle, but non-significant, effects were observed on the hippocampus and the hypothalamus in adult ethanol-exposed male offspring. Ethanol exposure was additionally associated with a trend toward decreased oxygen consumption, carbon dioxide production, and reduced daily energy expenditure, as well as significantly increased adiposity, albeit with normal body weight and food intake, in adult male offspring. In summary, ethanol exposure restricted to early gestation had subtle long-term effects on the structure of specific brain regions in male offspring. The sensitivity of the hippocampus to ethanol-induced damage is reminiscent of that reported by other studies - despite differences in the level, timing, and duration of exposure - and likely contributes to the cognitive impairment that characteristically results from prenatal ethanol exposure. The hypothalamus plays an important role in regulating metabolism and energy homeostasis. Our finding of altered daily energy expenditure and adiposity in adult ethanol-exposed males is consistent with the idea that central nervous system abnormalities also underpin some of the metabolic phenotypes associated with ethanol exposure in pregnancy.

Social buffering of the maternal and infant HPA axes: Mediation and moderation in the intergenerational transmission of adverse childhood experiences

Supportive social relationships can reduce both psychological and physiological responses to stressful experiences. Recently, studies have also assessed the potential for social relationships to buffer the intergenerational transmission of stress. The majority of these studies, however, have focussed on social learning as a mechanism responsible for the intergenerational transmission of stress. Evidence of biological mechanisms is lacking. The objective of the current study was, therefore, to determine whether the association between maternal adverse childhood experiences (ACEs) and infant hypothalamic-pituitary-adrenal (HPA) axis function is mediated by maternal HPA axis function during pregnancy and moderated by social support. Data were from 243 mother-infant dyads enrolled in a prospective longitudinal cohort (the Alberta Pregnancy Outcomes and Nutrition Study). Maternal history of ACEs was retrospectively assessed while maternal perceived social support and salivary cortisol were assessed prospectively at 6-22 weeks gestation (Time 1) and 27-37 weeks gestation (Time 2), and infant cortisol reactivity to a laboratory stressor and maternal perceived social support were assessed at 5-10 months postnatal (Time 3). Results revealed that maternal HPA axis function during pregnancy mediated the effects of maternal ACEs on infant HPA axis reactivity, suggesting that the maternal HPA axis is a mechanism by which maternal early life stress is transmitted to offspring. Furthermore, social support in the prenatal and postnatal periods moderated the cascade from maternal ACEs to infant HPA axis reactivity. Specifically, prenatal social support moderated the association between ACEs and maternal HPA axis function during pregnancy, and postnatal social support moderated the association between maternal HPA axis function and infant cortisol reactivity. These findings highlight the social sensitivity of the HPA axis and suggest the utility of social relationships as an intervention target to reduce the effects of maternal early life stress on infant outcomes.

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.

Intergenerational transmission of adverse childhood experiences via maternal depression and anxiety and moderation by child sex

Adverse childhood experiences (ACEs) of parents are associated with a variety of negative health outcomes in offspring. Little is known about the mechanisms by which ACEs are transmitted to the next generation. Given that maternal depression and anxiety are related to ACEs and negatively affect children's behaviour, these exposures may be pathways between maternal ACEs and child psychopathology. Child sex may modify these associations. Our objectives were to determine: (1) the association between ACEs and children's behaviour, (2) whether maternal symptoms of prenatal and postnatal depression and anxiety mediate the relationship between maternal ACEs and children's behaviour, and (3) whether these relationships are moderated by child sex. Pearson correlations and latent path analyses were undertaken using data from 907 children and their mothers enrolled the Alberta Pregnancy Outcomes and Nutrition study. Overall, maternal ACEs were associated with symptoms of anxiety and depression during the perinatal period, and externalizing problems in children. Furthermore, we observed indirect associations between maternal ACEs and children's internalizing and externalizing problems via maternal anxiety and depression. Sex differences were observed, with boys demonstrating greater vulnerability to the indirect effects of maternal ACEs via both anxiety and depression. Findings suggest that maternal mental health may be a mechanism by which maternal early life adversity is transmitted to children, especially boys. Further research is needed to determine if targeted interventions with women who have both high ACEs and mental health problems can prevent or ameliorate the effects of ACEs on children's behavioural psychopathology.

The Neurobiology of Attachment: From Infancy to Clinical Outcomes

Attachment theory was developed by John Bowlby in the 1950s. He defined attachment as a specific neurobiological system that resulted in the infant connecting to the primary caretaker in such a way to create an inner working model of relationships that continues throughout life and affects the future mental health and physical health of the infant. Given the significance of this inner working model, there has been a tremendous amount of research done in animals as well as humans to better understand the neurobiology. In this article the neurobiology of early development will be outlined with respect to the formation of attachment. This article will review what we have begun to understand as the neurobiology of attachment and will describe how the relationship with the primary caretaker affects the infant in a way leading to neurobiological changes that later in life affect emotional responses, reward, and perception difficulties that we recognize as psychiatric illness and medical morbidity.

Maternal sensitivity and social support protect against childhood atopic dermatitis

BACKGROUND

Many studies have identified associations between qualities of maternal-child relationships and childhood asthma, but few have examined associations with childhood atopic dermatitis (AD), a common precursor to asthma. Moreover, maternal psychological distress, including prenatal and postnatal depression, anxiety and stress, may increase risk, while social support from partners may reduce risk for childhood AD. We sought to uncover the association between maternal-infant relationship qualities (maternal sensitivity towards infant behavioral signals, controlling behavior, and unresponsiveness) and child AD after accounting for risk (i.e., prenatal and postnatal maternal depression, anxiety and stress) and protective (i.e., social support) factors.

METHODS

We conducted a secondary analysis of data collected on a subsample of 242 women and their infants enrolled during pregnancy in the ongoing Alberta Pregnancy Outcomes and Nutrition cohort study. Inclusion criteria required mothers to be >16 years of age, English speaking and <22 weeks gestational age at enrollment. Data on depression, anxiety and stress in the prenatal and postnatal periods and physician diagnosis of childhood AD at 18 months were gathered via maternal report. Maternal sensitivity, unresponsiveness and controlling behaviours were assessed via videotaped observations using the Child-Adult Relationship Experimental (CARE)-Index at 6 months of infant age.

RESULTS

Higher maternal sensitivity, or the inability of the mother to appropriately understand and respond to infant needs based on behavioral signals, predicted reduced odds of AD independent of and in combination with low prenatal and postnatal anxiety and high paternal support. After adjustment, higher maternal controlling behaviours and unresponsiveness also predicted greater odds of AD.

CONCLUSIONS

Low maternal sensitivity is a risk factor for childhood AD, independently and in combination with perinatal anxiety and low social support. Thus, interventions that improve maternal-infant relationship quality, especially sensitivity, reduce anxiety and improve social support from partners could reduce odds of childhood AD.

Prenatal maternal cortisol concentrations predict neurodevelopment in middle childhood

Glucocorticoids (cortisol in humans) are the end product of the hypothalamic-pituitary-adrenocortical (HPA) axis and are proposed as a key mechanism for programming fetal brain development. The present prospective longitudinal study evaluates the association between prenatal maternal cortisol concentrations and child neurodevelopment. Participants included a low risk sample of 91 mother-child pairs. Prenatal maternal plasma cortisol concentrations were measured at 19 and 31 gestational weeks. Brain development and cognitive functioning were assessed when children were 6-9 years of age. Structural magnetic resonance imaging scans were acquired and cortical thickness was determined. Child cognitive functioning was evaluated using standardized measures (Wechsler Intelligence Scale for Children IV and Expressive Vocabulary Test, Second Edition). Higher maternal cortisol concentrations during the third trimester were associated with greater child cortical thickness primarily in frontal regions. No significant associations were observed between prenatal maternal cortisol concentrations and child cortical thinning. Elevated third trimester maternal cortisol additionally was associated with enhanced child cognitive performance. Findings in this normative sample of typically developing children suggest that elevated maternal cortisol during late gestation exert lasting benefits for brain development and cognitive functioning 6-9 years later. The benefits of fetal exposure to higher maternal cortisol during the third trimester for child neurodevelopment are consistent with the role cortisol plays in maturation of the human fetus. It is plausible that more extreme elevations in maternal cortisol concentrations late in gestation, as well as exposure to pharmacological levels of synthetic glucocorticoids, may have neurotoxic effects on the developing fetal brain.