Cortisol response to the Trier Social Stress Test in pregnant women at risk for postpartum depression

Stress-related eating in pregnancy? An RCT examining links between prenatal stress and food choices

BACKGROUND

Diet quality during pregnancy is important for maternal health and offspring development. However, national dietary recommendations are not always met. A potential barrier for healthy food choices might be the experience of stress. Previous literature in non-pregnant populations suggests a negative effect of acute stress on diet quality. This preregistered study is the first to test whether an acute stressor leads to unhealthy food choices in pregnancy and examine the moderating role of stress, depressive and anxiety complaints in daily life.

METHOD

Pregnant women (N = 110, 3rd trimester) completed online self-reported surveys measuring stress, depressive and anxiety complaints in daily life. Hereafter, participants were invited for a laboratory visit, in which they were exposed to the Trier Social Stress Test or a control task. After this manipulation, self-reported and actual food choices and food intake were assessed. At the end of the visit, a hair sample was collected. Throughout the visit, visual analogue scales on negative affect were completed and saliva samples were collected.

RESULTS

The stress group experienced significantly more psychological stress than the control group during the experimental manipulation. Main regression analyses showed that the acute laboratory stressor did not cause unhealthy food choices in the third trimester of pregnancy. In fact, the stress group chose fewer unhealthy foods and consumed fewer kilocalories compared to the control group. Additionally, the findings point at a moderating role of depressive and stress complaints in daily life on food choices within the control group: higher scores were related to more unhealthy food choices and more kilocalories consumed.

DISCUSSION

As this was the first study to test the effect of an acute stressor on food choices in pregnant women, more research is needed to obtain a better understanding of stress-related eating in pregnancy. This knowledge may inform future interventions to support pregnant women in improving their diet quality.

The effects of IPV and mental health symptoms on HPA axis functioning during early pregnancy

Maternal HPA axis dysregulation during early pregnancy can negatively affect maternal functioning. However, findings are mixed regarding how intimate partner violence (IPV), a common traumatic stressor, impacts HPA axis regulation during pregnancy. Interactions between IPV and mental health symptoms as they influence cortisol production are rarely examined, especially among pregnant women. Therefore, this study examined the impact of IPV, mental health symptoms, and their interactions on the maternal HPA axis during early pregnancy; 255 pregnant women, oversampled for experiences of IPV, completed a laboratory stressor and measures of depressive and post-traumatic stress symptoms (PTSS) at 15-18 weeks of pregnancy. Participants provided saliva samples following the Trier Social Stress Test that were assayed for cortisol; the area under the curve with respect to ground (AUCg) was computed as a measure of cortisol reactivity. The interactive effects of IPV, depressive symptoms, and PTSS on AUCg were significant, but the main effects were not. At low levels of depressive symptoms, the association between IPV and AUCg was negative; at moderate levels of depressive symptoms, it was not significant, and at high levels, it was positive. At low and moderate levels of PTSS, the effects of IPV on cortisol AUCg were not significant, but at high levels, the association was positive. IPV during early pregnancy was associated with both hyperactive and blunted stress reactivity, depending on the type and severity of mental health symptoms. These patterns of dysregulation of the HPA axis may have differential effects both for women's functioning throughout pregnancy as well as for the offspring.

The role of stress in perinatal depression and anxiety - A systematic review

Perinatal depression (PND) and anxiety affect around 20% of women, but available pharmacotherapy is not sufficiently effective in 20-60% of them, indicating a need for better understanding of these diseases. Since stress is a significant risk factor for PND, the aim was to examine the role of biological, environmental and psychological stress in PND and anxiety through a systematic literature search. Overall 210 studies were included, among which numerous rodent studies showed that perinatal stress induced depressive-like and anxious behavior, which was associated with HPA-axis alterations and morphological brain changes. Human studies indicated that the relationship between cortisol and perinatal depression/anxiety was not as clear and with many contradictions, although social and psychological stress were clearly positively associated with PND. Finally, oxytocin, synthetic neuroactive steroid and n-3 PUFA diet have been identified as potentially beneficial in the therapy of PND and anxiety, worth to be investigated in the future.

Cortisol reactivity to a laboratory stressor predicts increases in depressive symptoms in perinatal and nulliparous women during population-level stress

BACKGROUND

Research suggests a link between stress and depression, especially in high-risk groups. The perinatal period is known as a time of increased risk for depression and pregnancy has been associated with alterations in cortisol levels; however, limited research has assessed cortisol reactivity during pregnancy. Finally, no studies have yet examined whether cortisol reactivity predicts later depressive symptoms during a population-level stressor, such as the COVID-19 pandemic.

METHODS

The current study examined whether cortisol reactivity in perinatal and nulliparous women a year before the onset of COVID-19 predicted increases in depressive symptoms during the initial stage of the pandemic. Participants were 68 women (33 pregnant, Mage = 30.6; 35 nulliparous, Mage = 28.4) who, approximately a year before COVID-19, responded to a depressive symptoms questionnaire and completed a psychosocial stress test, during which they provided salivary cortisol samples. Shortly after the onset of pandemic-related closures (April 2020; postpartum for previously pregnant participants), participants completed follow-up questionnaires assessing current depressive symptoms.

RESULTS

Analyses showed that cortisol reactivity at baseline predicted increases in depressive symptoms at follow-up. Perinatal and nulliparous women did not differ in this association.

LIMITATIONS

The present study was limited by a moderate sample size and heterogeneity in terms of gestational week, restricting inferences about specific stages of pregnancy.

CONCLUSIONS

Our findings suggest that cortisol reactivity to a laboratory stressor is a biomarker of risk for increased depressive symptoms during ecological stress in women. Biomarkers like these increase our understanding of depression risk and may help to identify individuals in need of interventions.

Physiological and affective responses to green space virtual reality among pregnant women

BACKGROUND

Benefits of green spaces on stress reduction have been shown in previous studies. Most existing studies to date have focused on the general population. However, there is a lack of understanding of physiological mechanisms underlying the beneficial effects of green space among special populations, such as pregnant women.

OBJECTIVES

To examine physiological and affective responses to green space on stress recovery among pregnant women, using simulated green space exposure through virtual reality (VR).

METHODS

We recruited 63 pregnant women between 8 and 14 weeks' gestational age for a laboratory experiment. Participants were randomly assigned to view one of three, 5-min, VR videos of an urban scene with different green space levels (i.e., non-green, moderate, and high) after a laboratory stressor, the Trier Social Stress Test. Physiological stress responses were measured via changes in blood pressure, heart rate, skin conductance level, salivary alpha-amylase, and salivary cortisol. Affective response was measured using the Positive and Negative Affect Scale.

RESULTS

We found that visual exposure to a green space environment in VR was associated with both physiological and affective stress reduction among pregnant women, including lower systolic blood pressure [-4.6 mmHg, 95% confidence interval (CI): -8.8, -0.4], reduced salivary alpha-amylase concentration (-1.2 ng/ml, 95% CI: -2.2, -0.2), improved overall positive affect (score: 6.6, 95% CI: 0.3, 13.0) and decreased negative affect of anxiety (score: -2.6, 95% CI: -5.19, -0.04) compared to non-green space environment. Exposure to high green space environment in park-like setting had the strongest impacts on stress recovery.

CONCLUSION

This study demonstrated that virtual green space exposure could effectively ease stress and improve mental health and well-being during pregnancy. Even a short immersion in VR-based green space environment may bring health benefits, which has significant implications for pregnant women when access to an actual nature may not be possible.

Relationship between psychological stress and ghrelin concentrations in pregnant women with overweight or obesity

Exposure to, perception of, and response to stress have all been shown to influence appetite and dietary behaviors in non-pregnancy human and animal studies, mediated in part by the appetite stimulating hormone ghrelin. Yet, the impact of prenatal stress on biological pathways associated with appetite in the context of pregnancy is not well understood. The objective of this study was to assess the relationship between these layered dimensions of stress with fasting and postprandial plasma ghrelin concentrations among Hispanic pregnant women with overweight or obesity, a population known to experience heightened levels of stress. Thirty-three non-diabetic Hispanic women with pre-pregnancy body mass index of 25.0-34.9 kg/m2 participated in a crossover study at 28-32 weeks' gestation. At each visit, participants provided fasting blood and saliva samples, consumed a standardized mixed-meal, and completed a 15-minute task: friendly conversation (control) or the Trier Social Stress Test (experimental stress exposure). Six timed blood and saliva samples were collected up to 2 h from baseline and assayed for ghrelin and cortisol, respectively, and area-under-the-curve (AUC) values were computed. Day-to-day stress levels were assessed by the Perceived Stress Scale. Physiological and psychological stress reactivity was determined by cortisol AUC and change in self-reported affect state, respectively, during the experimental stress visit. Maternal perceived stress was positively associated with ghrelin concentrations in the fasted (β = 0.06, p = 0.02) and postprandial state (β = 0.05, p = 0.02). Mean ghrelin AUC was not significantly different following acute stress versus control. Measures of acute stress reactivity were not associated with ghrelin AUC. Contrary to our hypothesis, among Hispanic pregnant women with overweight and obesity, exposure to an acute stress induction task did not alter postprandial ghrelin concentrations, and changes in individual psychological and physiological stress reactivity did not associate with postprandial ghrelin. However, our findings suggest that maternal report of general perceived stress over the last month is associated with higher fasting and postprandial ghrelin concentrations. Differences in the effects of short-term stress exposure versus day-to-day perception of stress on appetite and food intake in pregnancy deserves further investigation.

Prenatal stress assessment using heart rate variability and salivary cortisol: A machine learning-based approach

OBJECTIVE

To develop a machine learning algorithm utilizing heart rate variability (HRV) and salivary cortisol to detect the presence of acute stress among pregnant women that may be applied to future clinical research.

METHODS

ECG signals and salivary cortisol were analyzed from 29 pregnant women as part of a crossover study involving a standardized acute psychological stress exposure and a control non-stress condition. A filter-based features selection method was used to identify the importance of different features [heart rate (HR), time- and frequency-domain HRV parameters and salivary cortisol] for stress assessment and reduce the computational complexity. Five machine learning algorithms were implemented to assess the presence of stress with and without salivary cortisol values.

RESULTS

On graphical visualization, an obvious difference in heart rate (HR), HRV parameters and cortisol were evident among 17 participants between the two visits, which helped the stress assessment model to distinguish between stress and non-stress exposures with greater accuracy. Eight participants did not display a clear difference in HR and HRV parameters but displayed a large increase in cortisol following stress compared to the non-stress conditions. The remaining four participants did not demonstrate an obvious difference in any feature. Six out of nine features emerged from the feature selection method: cortisol, three time-domain HRV parameters, and two frequency-domain parameters. Cortisol was the strongest contributing feature, increasing the assessment accuracy by 10.3% on average across all five classifiers. The highest assessment accuracy achieved was 92.3%, and the highest average assessment accuracy was 76.5%.

CONCLUSION

Salivary cortisol contributed a significant increase in accuracy of the assessment model compared to using a range of HRV parameters alone. Our machine learning model demonstrates acceptable accuracy in detection of acute stress among pregnant women when combining salivary cortisol with HR and HRV parameters.

Peripartum depression: Does risk versus diagnostic status impact mother-infant bonding and perceived social support?

BACKGROUND

Peripartum depression (PND) impairs mother-infant boding and perceived social support, yet limited research has examined if women at-risk for PND (AR-PND) also experience impairment. We examined if pregnant women AR-PND, women with PND, and healthy comparison women (HCW) differed in their mother-infant bonding and social support. As PND is highly comorbid with anxiety, we also examined if peripartum anxiety impacted postpartum diagnosis of PND.

METHODS

A total of 144 pregnant women AR-PND or euthymic were assessed twice antepartum and twice postpartum. We utilized regression models to examine the impact of PND risk group status and diagnostic status on mother-infant bonding and perceived social support postpartum. We conducted a sensitivity analysis using a generalized estimating equations model to determine if anxiety (Hamilton Anxiety Rating Scale, HAM-A) across all four time points was associated with the postpartum diagnosis of PND.

RESULTS

Women AR-PND experienced significantly worse mother-infant bonding compared to HCW (p = .03). Women diagnosed with PND experienced significantly worse mother-infant bonding and social support compared to HCW (p = .001, p = .002, respectively) and to those who were at-risk for but did not develop PND (p = .02, p = .008, respectively). HAM-A severity at each visit was associated with PND diagnosis status, where each increase in HAM-A was associated with 15% increased odds of being diagnosed with PND postpartum.

CONCLUSIONS

Both women AR-PND and those with PND experience worse mother-infant bonding. Peripartum anxiety should also be assessed as it represents a marker for later PND.

Behavioral and physiological stress responses: Within-person concordance during pregnancy

During pregnancy, a woman's emotions can have longstanding implications for both her own and her child's health. Within-person emotional concordance refers to the simultaneous measurement of emotional responses across multiple levels of analysis. This method may provide insight into how pregnant women experience emotions in response to stress. We enrolled 162 pregnant women and assessed concordance through autonomic physiology (electrodermal activity [EDA], respiratory sinus arrhythmia [RSA]), and coded behavior (Prosocial, Flight, Displacement) during the Trier Social Stress Test-Speech. We used multilevel models to examine behavioral-physiological concordance and whether self-reported emotion dysregulation moderated these effects. Participants exhibited EDA-Prosocial concordance, suggesting that prosocial behavior may be a marker of stress. Emotion dysregulation did not moderate concordance. These findings provide novel information about behavioral coping to stress in pregnancy. Given the importance of observed behavior in the maintenance and treatment of psychopathology, these findings may provide a launchpad for future perinatal intervention research.

Perinatal depression: Heterogeneity of disease and in animal models

Perinatal depression (PND) can have either an antepartum or postpartum onset. Although the greatest risk factor for PND is previous depression history,de novoPND occurs with the majority of cases occurring in the postpartum. Timing of depression can impact etiology, prognosis, and response to treatment. Thus, it is crucial to study the impact of the heterogeneity of PND for better health outcomes. In this review, we outline the differences between antepartum and postpartum depression onset of PND. We discuss maternal physiological changes that differ between pregnancy and postpartum and how these may differentially impact depression susceptibility. We highlight changes in the maternal steroid and peptide hormone levels, immune signalling, serotonergic tone, metabolic factors, brain morphology, and the gut microbiome. Finally, we argue that studying the heterogeneity of PND in clinical and preclinical models can lead to improved knowledge of disease etiopathology and treatment outcomes.

Mothering revisited: A role for cortisol?

This selective review first describes the involvement of the maternal hypothalamic-pituitary-adrenal (HPA) axis during pregnancy and the postpartum period, and the relation between peripartum HPA axis function and maternal behavior, stress reactivity and emotional dysregulation in human mothers. To provide experimental background to this correlational work, where helpful, animal studies are also described. It then explores the association between HPA axis function in mothers and their infants, under ongoing non-stressful conditions and during stressful challenges, the moderating role of mothers' sensitivity and behavior in the mother-child co-regulation and the effects of more traumatic risk factors on these relations. The overarching theme being explored is that the HPA axis - albeit a system designed to function during periods of high stress and challenge - also functions to promote adaptation to more normative processes, shown in the new mother who experiences both high cortisol and enhanced attraction and attention to and recognition of, their infants and their cues. Hence the same HPA system shows positive relations with behavior at some time points and inverse ones at others. However, the literature is not uniform and results vary widely depending on the number, timing, place, and type of samplings and assessments, and, of course, the population being studied and, in the present context, the state, the stage, and the stress levels of mother and infant.

Pharmacotherapy of Postpartum Depression: Current Approaches and Novel Drug Development

Postpartum depression is one of the most common complications of childbirth. Untreated postpartum depression can have substantial adverse effects on the well-being of the mother and child, negatively impacting child cognitive, behavioral, and emotional development with lasting consequences. There are a number of therapeutic interventions for postpartum depression including pharmacotherapy, psychotherapy, neuromodulation, and hormonal therapy among others, most of which have been adapted from the treatment of major depressive disorder outside of the peripartum period. Current evidence of antidepressant treatment for postpartum depression is limited by the small number of randomized clinical trials, underpowered samples, and the lack of long-term follow-up. The peripartum period is characterized by rapid and significant physiological change in plasma levels of endocrine hormones, peptides, and neuroactive steroids. Evidence supporting the role of neuroactive steroids and γ-aminobutyric acid (GABA) in the pathophysiology of postpartum depression led to the investigation of synthetic neuroactive steroids and their analogs as potential treatment for postpartum depression. Brexanolone, a soluble proprietary intravenous preparation of synthetic allopregnanolone, has been developed. A recent series of open-label and placebo-controlled randomized clinical trials of brexanolone in postpartum depression demonstrated a rapid reduction in depressive symptoms, and has led to the submission for regulatory approval to the US Food and Drug Administration (decision due in March 2019). SAGE-217, an allopregnanolone analog, with oral bioavailability, was recently tested in a randomized, double-blind, placebo-controlled phase III study in severe postpartum depression, with reportedly positive results. Finally, a 3β-methylated synthetic analog of allopregnanolone, ganaxolone, is being tested in both intravenous and oral forms, in randomized, double-blind, placebo-controlled phase II studies in severe postpartum depression.

Ethnic differences in stress-induced cortisol responses:Increased risk for depression during pregnancy

Few studies have examined individual differences in stress reactivity during pregnancy. The current study examined whether cortisol responses to a laboratory stressor (Trier Social Stress Test; TSST) significantly differed within an ethnically diverse sample of 34 pregnant women (38% Latina, 29% African American) identified to be at low (n = 17; i.e., low depressive symptoms) versus high risk for depression (n = 17; i.e., past history of depression and/or high depressive symptoms). Women at high depression risk, particularly those with a past history of depression, showed greater cortisol responses to the TSST than women at low depression risk, controlling for gestational age, parity, and education (p = 0.03). Moreover, African American women, particularly those at high depression risk, showed blunted cortisol responses to the TSST compared to non-African American women (p = 0.02). Our results highlight risk factors for depression during pregnancy and have strong implications for reducing health disparities in this population.

The association between maternal cortisol and depression during pregnancy, a systematic review

Timing of cortisol collection during pregnancy is an important factor within studies reporting on the association between maternal cortisol and depression during pregnancy. Our objective was to further examine the extent to which reported associations differed across studies according to time of maternal cortisol collection during pregnancy. On December 15, 2016, records were identified using PubMed/MEDLINE (National Library of Medicine), EMBASE (Elsevier; 1974-), Cumulative Index to Nursing and Allied Health Literature (CINAHL, EBSCO), PsycINFO (EBSCO), and Web of Science Core Collection (Thomson Reuters). Unique abstracts were screened using the following inclusion criteria: (1) maternal cortisol assessed during pregnancy; (2) antepartum depression assessed during pregnancy using a screening instrument; (3) reports on the association between maternal cortisol and antepartum depression; (4) provides information on timing of cortisol assessment during pregnancy, including time of day and gestation; and (5) not a review article or a case study. One thousand three hundred seventy-five records were identified, resulting in 826 unique abstracts. Twenty-nine articles met all inclusion criteria. On balance, most studies reported no association between maternal cortisol and antepartum depression (N = 17), and saliva and blood were the most common reported matrices. Morning and second and third trimesters were the most common times of collection during pregnancy. Among studies reporting an association (N = 12), second-trimester and third-trimester cortisol assessments more consistently reported an association and elevated cortisol concentrations were observed in expected recovery periods. Our review adds to the existing literature on the topic, highlighting gaps and strategic next steps.