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

Pinpointing the timing of prenatal stress associated with infant biobehavioral reactivity

Prenatal stress has a well-established link to negative biobehavioral outcomes in young children, particularly for girls, but the specific timing during gestation of these associations remains unknown. In the current study, we examined differential effects of timing of prenatal stress on two infant biobehavioral outcomes [i.e., hypothalamic-pituitary-adrenal (HPA) axis reactivity and difficult temperament] that are early-life precursors to the development of psychopathology. We obtained the most granular assessment of prenatal stress to date involving weekly stress ratings from 396 pregnant women between 15 and 41 weeks gestation. At 6 months postpartum, infant salivary cortisol was collected (n = 173) before and after a stressful laboratory task and mothers reported on infant temperament (n = 244). Machine learning explored both between- and within-person regression effects of prenatal stress on the two infant biobehavioral outcomes. For HPA axis reactivity, we found a sensitive period during mid-gestation (weeks 20 and 29) for girls, but during late gestation (week 37) for boys. For difficult temperament, we found a between-persons effect of mean stress level as well as sensitive periods in mid (weeks 20, 21, 25) and late gestation (week 37) for girls, but across mid to late gestation (weeks 25, 27, 30, 34, 40) for boys. This study is the first to use a weekly assessment across gestation to demonstrate specific windows of sensitivity for infant biobehavioral precursors of child psychopathology. The findings highlight that biological sex critically influences specific timing of these prenatal stress associations with infant outcomes, thus informing our understanding of sex differences in early biobehavioral markers of psychopathology.

Stress and mental health symptoms in early pregnancy are associated with the oral microbiome

BACKGROUND

Research has revealed associations between microbes of the gastrointestinal tract and stress, anxiety and depression in pregnant or postpartum women. While these studies suggest a gut-brain-behaviour axis, no studies have examined microbes of the oral cavity in relation to maternal mental health.

OBJECTIVE

To explore a potential oral-brain-behaviour axis related to maternal mental health.

METHODS

Microbes were measured in saliva obtained from 224 second-trimester (mean±SD = 17±2 weeks) women oversampled for stress. Oralome data were associated with women's recent or cumulative pregnancy stress, trait and state anxiety, depression symptoms and post-traumatic stress disorder (PTSD) symptoms. Covariates explored included age, income, alcohol and tobacco use, dental issues and physical health problems.

RESULTS

Pregnant women in the high trait anxiety or depression symptom groups had higher oral alpha diversity, indicating higher richness of species within samples. Groups with high and low PTSD symptoms differed in beta diversity, reflecting differences in community composition. Linear discriminant analysis showed differently abundant microbes in women with high stress versus low life stress, anxiety, depression, and PTSD, with the affected microbes mostly differing by symptom. Notably, members of phylum Proteobacteria were more abundant in women with high recent life stress and Spirochaetes was more abundant in women with high depression symptoms. Members of phylum Firmicutes were more abundant in the high trait anxiety and high depression groups. Genus Dialister (previously found to be lower in the gut of depressed non-pregnant people) was higher in women experiencing either high trait or state anxiety, or experiencing high depression symptoms, while genus Eikenella was elevated with high trait anxiety, depression or PTSD.

CONCLUSIONS

The oral microbiome is associated with stress and mental health in pregnant women, in ways different from the gut microbiome or what has been found in non-pregnant people.

CLINICAL IMPLICATIONS

Understanding oral microbiome-mental health relations may reveal future microbial targets to improve maternal psychological well-being.

Economic Hardship Predicts Intimate Partner Violence Victimization During Pregnancy

Objective

Intimate partner violence (IPV) during pregnancy is associated with negative physical and mental health consequences for both mothers and infants. Economic hardship is often exacerbated during pregnancy and is associated with increased rates of IPV in non-pregnant samples. However, temporal associations between economic hardship and IPV victimization have not been well characterized during pregnancy. The present study used data collected at the weekly level to examine the interindividual and intraindividual effects of economic hardship on IPV victimization during pregnancy and determine whether longitudinal changes in IPV across pregnancy vary based on level of economic hardship.

Method

Two hundred ninety-four women reported on weekly experiences of IPV and economic hardship (i.e., food insecurity and other money problems) during weeks 17-40 of pregnancy. Participants were oversampled for low income and IPV exposure. Binary logistic multilevel models were used to test study hypotheses.

Results

Greater economic hardship on average during pregnancy predicted increased odds of IPV victimization. Within-person increases in economic hardship also predicted increased odds of IPV victimization in the same week. Although IPV victimization tended to decrease on average over the course of pregnancy, there was a significant time by economic hardship interaction such that IPV decreased more gradually for women reporting high levels of economic hardship.

Conclusions

The present study examined weekly patterns of IPV victimization across pregnancy in a low-income community sample. Results suggest that policies aimed at increasing families' economic security during the perinatal period may reduce the individual and societal burden of IPV.

CBD enhances the cognitive score of adolescent rats prenatally exposed to THC and fine-tunes relevant effectors of hippocampal plasticity

Introduction: An altered neurodevelopmental trajectory associated with prenatal exposure to ∆-9-tetrahydrocannabinol (THC) leads to aberrant cognitive processing through a perturbation in the effectors of hippocampal plasticity in the juvenile offspring. As adolescence presents a unique window of opportunity for "brain reprogramming", we aimed at assessing the role of the non-psychoactive phytocannabinoid cannabidiol (CBD) as a rescue strategy to temper prenatal THC-induced harm. Methods: To this aim, Wistar rats prenatally exposed to THC (2 mg/kg s.c.) or vehicle (gestational days 5-20) were tested for specific indexes of spatial and configural memory in the reinforcement-motivated Can test and in the aversion-driven Barnes maze test during adolescence. Markers of hippocampal excitatory plasticity and endocannabinoid signaling-NMDAR subunits NR1 and 2A-, mGluR5-, and their respective scaffold proteins PSD95- and Homer 1-; CB1R- and the neuromodulatory protein HINT1 mRNA levels were evaluated. CBD (40 mg/kg i.p.) was administered to the adolescent offspring before the cognitive tasks. Results: The present results show that prenatal THC impairs hippocampal memory functions and the underlying synaptic plasticity; CBD is able to mitigate cognitive impairment in both reinforcement- and aversion-related tasks and the neuroadaptation of hippocampal excitatory synapses and CB1R-related signaling. Discussion: While this research shows CBD potential in dampening prenatal THC-induced consequences, we point out the urgency to curb cannabis use during pregnancy in order to avoid detrimental bio-behavioral outcomes in the offspring.

Conducting Virtual Assessments in Developmental Research: COVID-19 Restrictions as a Case Example

Developmental researchers face considerable challenges regarding maximizing data collection and reducing participant attrition. In this article, we use our experiences implementing our study on the effects of timing of prenatal stress on maternal and infant outcomes during the COVID-19 pandemic as a framework to discuss the difficulties and solutions for these challenges, including the development of two types of virtual assessments. Specific information regarding use of virtual platforms, confidentiality, engaging children during video conferencing, and modifying the major assessments of our research are discussed. Feasibility data are presented, and data analytic challenges regarding statistical inference are outlined. Finally, we conclude with some of the unintended positive consequences for our research that resulted from making these modifications to our original methods.