Child development following fetal adversities. From neural to interactive processes of socio-emotional vulnerability in Intrauterine Growth Restricted infants

Recent years have witnessed a proliferation of contributions on antenatal growth vulnerabilities and the long-term consequences on neurodevelopment and health outcomes. Knowing the pre- and perinatal factors exposing neurodevelopment and behavioral growth would benefit early clinical decision making and timely interventions. The present doctoral thesis organizes a series of studies within the field of clinical developmental psychology investigating a model of the fetal origin of neurodevelopment. Specifically, the study of Intrauterine Growth Restriction (IUGR) is the doorway and the keystone for exploring the role of antenatal adversity in founding developmental cascades of effects drifting biobehavioral trajectories towards at-risk outcomes. The IUGR describes a set of nutritional anomalies affecting fetal maturation and exposing to high risk the post-natal growth. Most of the approaches investigating such adversity address urgent medical questions on etiopathology, fetal management and long-term prediction of health and mental health outcomes. The downside of this displacement is that the focus on the postnatal experience of the social and relational world in infants and children with IUGR is largely left behind. This issue clouds the comprehension of the relationship between antenatal and postnatal influences and further, of the complexity necessary to properly describe IUGR developmental trajectories. In the attempt to bring this lens to the observation of neuro and behavioral development following IUGR and to connect antenatal growth with the postnatal experiences, we designed a series of studies aimed at expanding the comprehension of the putative neuro-behavioral mechanisms linking growth restriction to later outcomes. Besides, achieving this goal would lay the ground for further exploring the potential routes of reversing mechanisms, thus aspiring in being clinically informative. The studies presented in this thesis are embedded in an integrated theoretical framework and a multimethod approach where child development results from multiple and transactional processes involving the interdependency of biological and environmental influences. Specifically, Chapter 1 describes a meta-analytic study ascertaining the effect of growth restriction on cognitive outcome and intellectual risk across childhood. Our findings robustly reveal that across infancy, childhood and middle-childhood individuals with Intrauterine Growth Restriction have systematically lower cognitive scores, increased borderline intellectual functioning and intellectual risk, compared to appropriate for gestational age (AGA) peers. Consistent results are reported for IUGR samples with either antenatal diagnosis or at-birth identification, as well as for comparisons within the study of preterm and term-born groups. Chapter 2 presents a cohort study investigating grey matter volumes around the time of birth in very preterm (VTP) IUGR and AGA newborns. Findings prove extensive alterations in brain volumes characterizing IUGR perinatal brain development. Additionally, the study identifies IUGR VPT cognitive and motor performances in toddlerhood as significantly lower than the ones of AGA VPT peers. Interestingly, perinatal volumetric alterations did not exert a predictive role on such outcomes, opening at the presence of further processes involved in these developmental trajectories. In line with this hypothesis, Chapter 3 presents the rationale and methods of a longitudinal case-control study investigating social and emotion processing in IUGR term-born infants, as putative neural and behavioral mechanisms translating antenatal vulnerability into atypical developmental outcomes. Extracted from this study, Chapter 4 reports on behavioral differences in between IUGR and AGA term-born infants during mother-infant interactions and on later cognitive outcomes. Preliminary findings suggest IUGR peculiar patterns of mother and infant interactive behaviors, with significantly lower levels of maternal structuring at 4 months and reduced infant’s responsiveness at 9 months. Also, they confirm later IUGR cognitive and motor risk as evaluated at 12 months of age. Finally, considering such mother-infant interactive vulnerability, Chapter 5 proposes the application of a pediatric video-feedback intervention to support parents of a Small for Gestational Age (SGA; birth weight below the 10th centile) newborn. Findings for this family allow to observe that the intervention holds parental worries about infant’s physical growth and sustains their mentalization abilities to recognizing his communicative skills and progressively identifying the self- and emotional regulatory abilities. Overall, our findings point out that fetal adversity, as described by IUGR, is a significant risk factor interesting child neurodevelopment, early exposing the brain and behavioral growth and parent-infant relational experiences. The studies proposed show the significance of observing multilevel processes and mechanisms that compose the crucial steps of a developmental cascade of cognitive and behavioral risk in order to understand the complexity of IUGR development. Consequently, in order to ameliorate the developmental outcomes of these children, constant and synergic research efforts should be directed to integrate different perspectives of study, explore the neighboring biobehavioral processes and to develop empirically-driven interventions targeting the processes of highest plasticity in IUGR development.