A soft baby carrier intervention enhances amygdala responses to infant crying in fathers: A randomized controlled trial

Neural processing of cry sounds in the transition to fatherhood: Effects of a prenatal intervention program and associations with paternal caregiving

This study examined whether neural processing of infant cry sounds changes across the transition to fatherhood (i.e., from the prenatal to postnatal period), and examined whether an interaction-based prenatal intervention modulated these changes. Furthermore, we explored whether postnatal activation in brain regions showing transition or intervention effects was associated with sensitive care and involvement. In a randomized controlled trial, 73 first-time expectant fathers were enrolled, of whom 59 had at least 1 available fMRI scan. Intervention and transition effects on cry processing were analyzed in the amygdala and superior frontal gyrus (SFG) using linear mixed effect models with all available data and with intent-to-treat analyses. Further, exploratory whole-brain analyses were performed. ROI analyses suggest that the transition to fatherhood is characterized by decreasing activation in response to cry vs control sounds in the amygdala but not SFG. Exploratory whole-brain analyses also show a decrease in activation over the transition to fatherhood in the sensorimotor cortex, superior lateral occipital cortex, hippocampus, and regions of the default mode network. In the putamen and insula, larger decreases were found in fathers with more adverse childhood caregiving experiences. In regions showing transitional changes, higher postnatal activation was associated with more concurrent parenting sensitivity. No effects of the intervention were found. The decrease in activation from the pre- to postnatal period may reflect fathers' habituation to cry sounds over repeated exposures. The positive association between postnatal neural activation and paternal sensitive care suggest that continued sensitivity to cry sounds may be conducive to parenting quality.

Infant carrying: Associations with parental reflective functioning, parental bonding and parental responses to infant crying

Infant carrying may have beneficial effects on the parent-infant relationship but only limited research has been conducted in this area. Therefore, the main aim of the current study was to investigate whether infant carrying is associated with parental reflective functioning, parental bonding, and parental (emotional) and behavioral responses to infant crying, key elements within the parent-infant relationship, promoting infant development. Parents reporting high levels (N = 389) of infant carrying (six times a week or daily) and parents reporting low levels (N = 128) of infant carrying (less than once a week or not at all) who participated in an online survey about the developing parent-infant relationship in Germany were included in the present study. Standardized questionnaires were used to assess parental reflective functioning, parental bonding impairments, and emotional responses to infant crying. Further insensitive (non-responsive and hostile) behaviors in response to infant crying were assessed. Parents with high levels of infant carrying showed better parental reflective functioning, lower parental bonding problems, less negative emotions, and less insensitive behaviors in response to infant crying.

Babywearing Reduces Urges to Use Substances in the Postpartum Period Among Mothers With OUDs

OBJECTIVES

While pregnancy presents a strong motivation to seek and comply with Opioid Use Disorder (OUD) treatment, the risk for relapse during the postpartum period is high. The purpose of the present study was to examine the impact of babywearing while admitted to the NICU on urges to use substances within 9 months of childbirth.

METHODS

Mothers with a history of OUD (N = 47, Mage = 28.91, SD = 5.14; 48.9% White, 19.1% Latinx) and their newborns were randomly assigned to the intervention (babywearing) or control (infant rocker) condition while admitted to a NICU. Interviews occurred every 3-months. Participants reported their strong desire or urge to use substances since the last interview. Approximately 68.1% had urges within 9 months. At 3 months, participants were categorized as: never babywore (0 h, N = 18), some babywearing (1-44 h, N = 13), consistent babywearing (45+ hours, i.e., minimum of 3.5 h per week, N = 16).

RESULTS

Condition X2(2, N = 47)=12.55, p < 0.001, Phi = 0.52 and babywearing category, X2(2, N = 47)=6.75, p = 0.034, Phi = 0.38 significantly predicted urges to use. Mothers in the intervention condition were more likely to report no urges to use: 56.5% had no urges (43.5% had urges) compared to 8.3% of control mothers (91.7% had urges). Mothers who consistently babywore had significantly fewer urges to use (43.8% had urges) compared to mothers who never babywore (83.3% had urges).

CONCLUSIONS FOR PRACTICE

There is a critical window to capitalize on mothers' desire to abstain from substance use. Babywearing, and specifically babywearing at least 30 min a day, reduced urges to use substances post-partum, a factor associated with relapse.

Randomized controlled trial to prevent postpartum depressive symptomatology: An infant carrier intervention

BACKGROUND

There is a need for effective interventions to reduce symptomatology of postpartum depression. The objective of this study was to test whether providing an ergonomic infant carrier would reduce postpartum depression symptomatology.

METHODS

A randomized two-arm, parallel-group trial with 100 participants was conducted between February 2018 and June 2019 in a low-income community. At 30-weeks' gestation, 50 participants were randomly assigned to receive an ergonomic infant carrier and instructions on proper use (intervention group), and 50 participants were assigned to a waitlist (control group). Participants tracked the extent of their infant carrier use and completed the Edinburgh Postpartum Depression Scale (EPDS) to assess postpartum depression symptomatology at 6-weeks postpartum.

RESULTS

Participants in the intervention group reported using an infant carrier significantly more often than the control group (β = 2.69, SE = 0.347, p < .001, 95 % CI = 2.08-3.41). The intervention group reported fewer depressive symptoms at 6-weeks postpartum than the control group (β = -0.541, p = .042).

LIMITATIONS

The sample size was relatively small and thus our results may not be generalizable to the general population.

CONCLUSION

Infant carrying may be a cost-effective intervention to reduce postpartum depression symptomatology. Large-scale studies are warranted to further examine the efficacy and cost-effectiveness of providing carriers as an intervention to reduce postpartum depression symptomatology.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov id: NCT04376021. Data Sharing Statement: Deidentified individual participant data will not be made available because we did not obtain permission to share individual data.

CLINICAL TRIAL REGISTRATION NUMBER

NCT0437602; https://beta.

CLINICALTRIALS

gov/study/NCT04376021.

Interventions from pregnancy to two years after birth for parents experiencing complex post-traumatic stress disorder and/or with childhood experience of maltreatment

BACKGROUND

Acceptable, effective and feasible support strategies (interventions) for parents experiencing complex post-traumatic stress disorder (CPTSD) symptoms or with a history of childhood maltreatment may offer an opportunity to support parental recovery, reduce the risk of intergenerational transmission of trauma and improve life-course trajectories for children and future generations. However, evidence relating to the effect of interventions has not been synthesised to provide a comprehensive review of available support strategies. This evidence synthesis is critical to inform further research, practice and policy approaches in this emerging area.

OBJECTIVES

To assess the effects of interventions provided to support parents who were experiencing CPTSD symptoms or who had experienced childhood maltreatment (or both), on parenting capacity and parental psychological or socio-emotional wellbeing.

SEARCH METHODS

In October 2021 we searched CENTRAL, MEDLINE, Embase, six other databases and two trials registers, together with checking references and contacting experts to identify additional studies.

SELECTION CRITERIA

All variants of randomised controlled trials (RCTs) comparing any intervention delivered in the perinatal period designed to support parents experiencing CPTSD symptoms or with a history of childhood maltreatment (or both), to any active or inactive control. Primary outcomes were parental psychological or socio-emotional wellbeing and parenting capacity between pregnancy and up to two years postpartum.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility of trials for inclusion, extracted data using a pre-designed data extraction form, and assessed risk of bias and certainty of evidence. We contacted study authors for additional information as required. We analysed continuous data using mean difference (MD) for outcomes using a single measure, and standardised mean difference (SMD) for outcomes using multiple measures, and risk ratios (RR) for dichotomous data. All data are presented with 95% confidence intervals (CIs). We undertook meta-analyses using random-effects models.

MAIN RESULTS

We included evidence from 1925 participants in 15 RCTs that investigated the effect of 17 interventions. All included studies were published after 2005. Interventions included seven parenting interventions, eight psychological interventions and two service system approaches. The studies were funded by major research councils, government departments and philanthropic/charitable organisations. All evidence was of low or very low certainty. Parenting interventions Evidence was very uncertain from a study (33 participants) assessing the effects of a parenting intervention compared to attention control on trauma-related symptoms, and psychological wellbeing symptoms (postpartum depression), in mothers who had experienced childhood maltreatment and were experiencing current parenting risk factors. Evidence suggested that parenting interventions may improve parent-child relationships slightly compared to usual service provision (SMD 0.45, 95% CI -0.06 to 0.96; I2 = 60%; 2 studies, 153 participants; low-certainty evidence). There may be little or no difference between parenting interventions and usual perinatal service in parenting skills including nurturance, supportive presence and reciprocity (SMD 0.25, 95% CI -0.07 to 0.58; I2 = 0%; 4 studies, 149 participants; low-certainty evidence). No studies assessed the effects of parenting interventions on parents' substance use, relationship quality or self-harm. Psychological interventions Psychological interventions may result in little or no difference in trauma-related symptoms compared to usual care (SMD -0.05, 95% CI -0.40 to 0.31; I2 = 39%; 4 studies, 247 participants; low-certainty evidence). Psychological interventions may make little or no difference compared to usual care to depression symptom severity (8 studies, 507 participants, low-certainty evidence, SMD -0.34, 95% CI -0.66 to -0.03; I2 = 63%). An interpersonally focused cognitive behavioural analysis system of psychotherapy may slightly increase the number of pregnant women who quit smoking compared to usual smoking cessation therapy and prenatal care (189 participants, low-certainty evidence). A psychological intervention may slightly improve parents' relationship quality compared to usual care (1 study, 67 participants, low-certainty evidence). Benefits for parent-child relationships were very uncertain (26 participants, very low-certainty evidence), while there may be a slight improvement in parenting skills compared to usual care (66 participants, low-certainty evidence). No studies assessed the effects of psychological interventions on parents' self-harm. Service system approaches One service system approach assessed the effect of a financial empowerment education programme, with and without trauma-informed peer support, compared to usual care for parents with low incomes. The interventions increased depression slightly (52 participants, low-certainty evidence). No studies assessed the effects of service system interventions on parents' trauma-related symptoms, substance use, relationship quality, self-harm, parent-child relationships or parenting skills.

AUTHORS' CONCLUSIONS

There is currently a lack of high-quality evidence regarding the effectiveness of interventions to improve parenting capacity or parental psychological or socio-emotional wellbeing in parents experiencing CPTSD symptoms or who have experienced childhood maltreatment (or both). This lack of methodological rigour and high risk of bias made it difficult to interpret the findings of this review. Overall, results suggest that parenting interventions may slightly improve parent-child relationships but have a small, unimportant effect on parenting skills. Psychological interventions may help some women stop smoking in pregnancy, and may have small benefits on parents' relationships and parenting skills. A financial empowerment programme may slightly worsen depression symptoms. While potential beneficial effects were small, the importance of a positive effect in a small number of parents must be considered when making treatment and care decisions. There is a need for further high-quality research into effective strategies for this population.

Sensitive responsiveness in expectant and new fathers

Fathers have an increasingly important role in the family and contribute through their sensitive responsiveness to positive child development. Research on parenting more often included fathers as caregivers in the past two decades. We present a neurobiological model of sensitive responsive parenting with a role for fathers' hormonal levels and neural connectivity and processing of infant signals. We tested this model in a research program ("Father Trials") with correlational and randomized experimental studies, and we review the results of these studies. So far, interaction-focused behavioral interventions seem most promising in supporting fathers' sensitive responsiveness, even though the mechanisms are still uncharted.

Scoping Review of Biological and Behavioral Effects of Babywearing on Mothers and Infants

OBJECTIVE

To synthesize the evidence on the biological and behavioral effects of babywearing on mothers and infants.

DATA SOURCES

We searched PubMed, CINAHL, Embase, PsycINFO, Sociological Abstracts, SCOPUS, and Google Scholar for peer-reviewed, full-text research articles published in English in which researchers reported on the biological or behavioral effects of babywearing on mothers or infants.

STUDY SELECTION

We reviewed the titles and abstracts of 200 records and abstracted 80 for full-text review. Of these, 29 studies met the eligibility criteria and were included in the review.

DATA EXTRACTION

We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) and extracted the following data from the included articles: author(s), year of publication, setting, aim/purpose, design, description, sample, results/outcomes, and implications to practice.

DATA SYNTHESIS

We synthesized data from the included studies into the following eight themes: Increased Contact, Responsiveness, and Secure Attachment; Physiologic Effects; Biomechanics and Positioning; Facilitating and Empowering; Comfort; Maternal Benefits; Speech, Vocalizations, and Tempo; and Beliefs and Perceptions About Babywearing.

CONCLUSION

Babywearing may have a range of beneficial biological and behavioral effects on mothers and infants. The evidence, however, is insufficient to inform practice recommendations, and additional research is warranted.

Parental protection in fathers with negative caregiving experiences: Heightened amygdala reactivity to infant threatening situations

Parental protection is an important, yet understudied, aspect of parenting behavior. Predictors of the quality of protection and potential underlying neural mechanisms are still unknown. In this study, we examined whether negative caregiving experiences in fathers' own childhood are related to protective behavior and neural reactivity to infant threatening situations. Paternal protective behavior was measured with self- and partner-reported protective behavior and behavioral observations in an experimental set-up (auditory startling task) in 121 first-time fathers (mean age child = 19.35 weeks, SD = 11.27). Neural activation during exposure to videos of infant-threatening (vs. neutral) situations was measured with functional magnetic resonance imaging (fMRI). We found a significant and positive association between negative caregiving experiences and amygdala reactivity to infant-threatening situations. A history of negative caregiving experiences was not significantly related to reported or observed paternal protective behavior. Our findings suggest that fathers with negative caregiving experiences show emotional hyperreactivity to cues of infant threat.

Convergent and divergent neural circuit architectures that support acoustic communication

Vocal communication is used across extant vertebrates, is evolutionarily ancient, and been maintained, in many lineages. Here I review the neural circuit architectures that support intraspecific acoustic signaling in representative anuran, mammalian and avian species as well as two invertebrates, fruit flies and Hawaiian crickets. I focus on hindbrain motor control motifs and their ties to respiratory circuits, expression of receptors for gonadal steroids in motor, sensory, and limbic neurons as well as divergent modalities that evoke vocal responses. Hindbrain and limbic participants in acoustic communication are highly conserved, while forebrain participants have diverged between anurans and mammals, as well as songbirds and rodents. I discuss the roles of natural and sexual selection in driving speciation, as well as exaptation of circuit elements with ancestral roles in respiration, for producing sounds and driving rhythmic vocal features. Recent technical advances in whole brain fMRI across species will enable real time imaging of acoustic signaling partners, tying auditory perception to vocal production.

Is paternal oxytocin an oxymoron? Oxytocin, vasopressin, testosterone, oestradiol and cortisol in emerging fatherhood

How do hormonal levels in men change from pregnancy to after the birth of their firstborn child, and what is the role of oxytocin, alone or in interplay with other hormones, in explaining variance in their parenting quality? We explored in 73 first-time fathers the development of five hormones that have been suggested to play a role in parenting: oxytocin (OT), vasopressin (AVP), testosterone (T), oestradiol (E2) and cortisol (Cort). In an extended group of fathers (N = 152) we examined associations with fathers' behaviour with their 2-month-old infants. OT and E2 showed stability from the prenatal to the postnatal assessments, whereas AVP and T decreased significantly, and Cort decreased marginally. OT on its own or in interplay with other hormones was not related to paternal sensitivity. Using an exploratory approach, the interaction between T and E2 emerged as relevant for fathers' sensitive parenting. Among fathers with high E2, high T was associated with lower sensitivity. Although we did not find evidence for the importance of OT as stand-alone hormone or in interplay with other hormones in this important phase in men's lives, the interaction between T and E2 in explaining variation in paternal behaviour is a promising hypothesis for further research. This article is part of the theme issue 'Interplays between oxytocin and other neuromodulators in shaping complex social behaviours'.

The effects of oxytocin and vasopressin administration on fathers' neural responses to infant crying: A randomized controlled within-subject study

In a randomized double-blind within-subject control study we investigated the effects of oxytocin and vasopressin administration on neural reactivity to infant cry sounds in 70 first-time fathers in the first year of fatherhood. Additionally, we examined whether effects of oxytocin and vasopressin administration on neural reactivity were moderated by fathers' early childhood experiences. Neural reactivity to infant cry sounds (versus control sounds) was measured using functional magnetic resonance imaging (fMRI). Furthermore, participants reported on their childhood experiences of parental harsh discipline and parental love withdrawal. Whole brain analyses revealed no significant effect of vasopressin or oxytocin administration on neural activation in response to infant cry sounds. Region of interest analyses showed decreased amygdala activation in both the oxytocin condition and the vasopressin condition as compared to placebo. We found no moderating effects of fathers' early childhood experiences. Our findings suggest that oxytocin administration may decrease feelings of anxiety or aversion to a crying infant. Whether decreased amygdala activation after vasopressin administration might be explained by contextual factors (e.g., absence of high levels of threat, unfamiliarity of the infant) or represents an affiliative response to infant distress warrants further investigation. Findings of the present study showed that oxytocin and vasopressin are important hormones implicated in neural models of infant cry perception in fatherhood.

Exploring the role of endocrine factors in sensitive parenting in men

Parental sensitivity has been studied extensively in parenting research. Recently, there has been increasing attention to endocrine factors that may be related to parental sensitivity, such as oxytocin, vasopressin, testosterone, and cortisol. Although hormones do not act in isolation, few studies integrated multiple hormones and examined their combined associations with parental sensitivity. The current study aimed to explore the hormonal correlates of paternal sensitivity by examining in 79 first-time fathers of young infants (2-4 months old) (1) the separate and combined associations of basal oxytocin, vasopressin, testosterone, and cortisol levels with sensitivity, and (2) the associations between paternal sensitivity and oxytocin, vasopressin, testosterone, and cortisol reactivity following father-infant interactions. We additionally explored whether interactions between the various basal hormone levels could predict paternal sensitivity. Saliva for the quantification of fathers' hormone levels was sampled before and after an interaction with their infant to determine basal levels and reactivity. Results revealed no significant associations between sensitivity and basal hormone levels or reactivity. However, results indicated that cortisol and testosterone interacted in their effects on paternal sensitive parenting. Namely, fathers with low basal cortisol levels showed more sensitivity with increasing T levels, but fathers with high cortisol levels were less sensitive with increasing T levels. However, it should be noted that the latter slope was not significantly different from zero. These findings suggest that variations in parental sensitivity might be better explained by interactions between hormones than by single hormone levels.

The Neural Basis of Human Fatherhood: A Unique Biocultural Perspective on Plasticity of Brain and Behavior

With the growing involvement of fathers in childrearing and the application of neuroscientific tools to research on parenting, there is a need to understand how a father's brain and neurohormonal systems accommodate the transition to parenthood and how such neurobiological changes impact children's mental health, sociality, and family functioning. In this paper, we present a theoretical model on the human father's brain and the neural adaptations that take place when fathers assume an involved role. The neurobiology of fatherhood shows great variability across individuals, societies, and cultures and is shaped to a great extent by bottom-up caregiving experiences and the amount of childrearing responsibilities. Mechanisms of mother-father coparental brain coordination and hormonal correlates of paternal behavior are detailed. Adaptations in the father's brain during pregnancy and across the postpartum year carry long-term implications for children's emotion regulation, stress management, and symptom formation. We propose a new conceptual model of HEALthy Father Brain that describes how a father's brain serves as a source of resilience in the context of family adversity and its capacity to "heal", protect, and foster social brain maturation and functionality in family members via paternal sensitivity, attunement, and support, which, in turn, promote child development and healthy family functioning. Father's brain provides a unique model on neural plasticity as sustained by committed acts of caregiving, thereby affording a novel perspective on the brain basis of human affiliation.