Prenatal intimate partner violence exposure predicts infant biobehavioral regulation: Moderation by the brain-derived neurotrophic factor ( BDNF ) gene

Prenatal Exposure to Intimate Partner Violence and Child Developmental Outcomes: A Scoping Review Study

Pregnant women face an increased risk of intimate partner violence (IPV). In addition to the risk of violence faced by women, there is a dual concern for risk of harm to the fetus. Expanding knowledge on childbirth outcomes, other domains of children's development have been examined in recent literature. Yet, there is limited comprehensive knowledge in the area. This scoping review study, informed by ecobiodevelopmental theory, mapped evidence associating prenatal IPV exposure and children's development. We searched eight databases, including PubMed, CINAHL, and ERIC. Thirty-one empirical studies published in English that associated prenatal IPV exposure and children's development were eligible for our review. Included studies were published between 2006 and 2022, with 39% published in the most recent 5 years. Eighteen studies had sample sizes smaller than 500, and 21 were atheoretical; six failed to consider covariates. Reviewed studies showed adverse effects of prenatal IPV exposure on psychological, behavioral, physical health, and physiological outcomes, either directly or indirectly via mechanisms such as maternal behavioral health. Due to inconsistency in results and a lack of empirical evidence, however, social and cognitive outcomes were identified as needing further research to enhance our understanding of the global and domain-specific effects of prenatal IPV exposure. Prospective longitudinal studies, driven by theories of causal mechanisms, which adjust for empirically qualified confounders, will be critical to inform practice and policy to promote healthy development of prenatally IPV-exposed children. Incorporating strengths/asset-focused outcomes and examining contextual factors and sex/gender specific effects may advance the knowledge in this area.

The impact of prenatal maternal stress due to potentially traumatic events on child temperament: A systematic review

The objective of the current study was to complete a systematic review of the relationship between prenatal maternal stress due to potentially traumatic events (PTEs) and child temperament. Eligible studies through June 2020 were identified utilizing a search strategy in PubMed and PsycInfo. Included studies examined associations between prenatal maternal stress due to PTE and child temperament. Two independent coders extracted study characteristics and three coders assessed study quality. Of the 1969 identified studies, 20 met full inclusion criteria. Studies were classified on two dimensions: (1) disaster-related stress and (2) intimate partner violence during pregnancy. For disaster-related prenatal maternal stress, 75% (nine out of 12) of published reports found associations with increased child negative affectivity, 50% (five out of 10) also noted associations with lower effortful control/regulation, and 38% (three out of eight) found associations with lower positive affectivity. When considering prenatal intimate partner violence stress, 80% (four out of five) of published reports found associations with higher child negative affectivity, 67% (four out of six) found associations with lower effortful control/regulation, and 33% (one out of three) found associations with lower positive affectivity. Prenatal maternal stress due to PTEs may impact the offspring's temperament, especially negative affectivity. Mitigating the effects of maternal stress in pregnancy is needed in order to prevent adverse outcomes on the infant's socioemotional development.

Disentangling Associations Among Maternal Lifetime and Prenatal Stress, Psychological Functioning During Pregnancy, Maternal Race/Ethnicity, and Infant Negative Affectivity at Age 6 Months: A Mixtures Approach

Purpose: Maternal stress and psychological dysfunction in pregnancy are independently linked with fetal neurodevelopment. Stress encompasses environmental stressors and psychological and physiological responses. Stressors and psychopathology co-occur with patterns differing by race/ethnicity. We aimed to extend environmental mixtures methodology to elucidate prenatal stress associations with infant negative affectivity (NA) in a racially/ethnically mixed cohort. Methods: Participants were mother/infant dyads (n=445) in a prospective pregnancy cohort study in two urban US settings in 2011-2018. During pregnancy, women completed the Life Stressor Checklist-Revised, Crisis in Family Systems-Revised, Edinburgh Postnatal Depression Scale, and post-traumatic stress disorder (PTSD) Checklist-Civilian version; the Infant Behavior Questionnaire-Revised assessed NA in 6-month olds. Using weighted quantile sum (WQS) regression, we developed a weighted maternal stress index encompassing lifetime and current life events and symptoms of depression and PTSD. Stress-by-race/ethnicity interactions allowed differential contributions of individual stress domains by maternal race/ethnicity. Results: Mothers were majority black (44%) or Hispanic (37%). Stress questionnaire and infant NA scores were similar by race/ethnicity. The WQS prenatal stress score was positively associated with infant NA (β: 0.40 [95% confidence interval 0.16-0.64]). PTSD was the strongest contributor to the WQS score in Hispanic women (59%), whereas in black women, lifetime stress and depressive symptoms accounted for 38% and 35%, respectively, of the association with NA. Conclusions: Extending environmental mixtures methodology to stress research may disentangle complex associations among lifetime and current stressful life events and psychological symptomatology and their contributions to early childhood neurobehavioral outcomes. Consideration of effect modification by race/ethnicity may inform understanding of differing vulnerability across racial/ethnic groups.

Salivary cortisol reactivity to psychological stressors in infancy: A meta-analysis

Measurement of salivary cortisol is a practical and non-invasive tool for studying stress reactivity to various types of stressors even in young infants. Whereas studies using physical stressors during the first months of life have found robust cortisol responses to painful stimuli, research with older infants using psychological stressors (e.g., parental separation) has produced mixed findings, limiting our understanding of potential developmental changes in cortisol reactivity across infancy. In the present study, we used meta-analysis to systematically investigate whether psychological stressor paradigms are associated with measurable cortisol responses in infants under 18 months of age and whether the magnitude of the responses is moderated by the type of psychological stressor (i.e., separation, frustration, novelty, or disruption of parental interaction), infant age, and other potential moderators. Across 47 studies (N = 4095, age range: 3-18 months), we found that commonly used psychological stressor paradigms are associated with a small (Hedges' g = .11) increase in salivary cortisol levels in typically developing infants. Stressor type moderated the effect sizes, and when effect sizes in each category were analyzed separately, only the separation studies were associated with a consistent increase in cortisol following the stressor. Age did not moderate the effect sizes either in the full set of studies or within the separate stressor types. These meta-analytic results indicate that the normative cortisol response to psychological stressors across infancy is small and emphasize the need for standardized stressor paradigms to assess cortisol responses systematically across infancy.

Role of neurotrophins in pregnancy, delivery and postpartum

Neurotrophins (NTs) are a family of polypeptides whose functions have been extensively studied in the past two decades. In particular, Nerve Growth Factor (NGF) and Brain-Derived Neurotrophic Factor (BDNF) play a major role in the development, nutrition and growth of the central and peripheral nervous system and in the pathogenesis of neurodegenerative, cardiometabolic and (auto)immune diseases. However, NGF and BDNF have subtle functions for follicular development, implantation, and placentation. This short narrative review summarizes the existing evidence, published between 2000 and 2019, about the role of NTs in many different conditions that might affect women during and after pregnancy such as preeclampsia, gestational diabetes, obesity, depression, anxiety, smoking and alcohol abuse. Literature suggests that the dysregulation of synthesis and release of NTs may lead to decisive effects on both maternal and fetal health. Some piece of evidences was found about a possible association between NGF/BDNF and breastfeeding. Additional studies on human models are necessary to further characterize the role of NTs in life-changing experiences like labor and delivery.