Influence of prenatal stress and postnatal maternal behaviour on child temperament and coping with stress

There is some evidence from both animal literature and human studies to suggest that maternal emotional well-being during pregnancy, as well as maternal behaviour during early childhood, can have important implications for the development of child temperament and children's distress reactivity and recovery (Albers, Riksen-Walraven, Sweep & de Weerth, 2008 Huizink, Mulder & Buitelaar, 2004 Leerkes, Blakson, and O'Brien, 2009). This thesis consists of two parts. The first part explored what measures of prenatal stress and anxiety are related to infant birth outcomes, temperament and cognition. The second part explored the role of maternal sensitivity and intrusiveness in child behavioural and endocrinological coping with stress across the first three years of life, concurrently and longitudinally. It was found that even relatively small fluctuations in prenatal stress and pregnancy- related anxiety in a normal sample of healthy women can still have an impact on infant birth outcomes and temperament in the first six months postnatally. In addition, maternal and amniotic fluid Cortisol levels during early pregnancy were positively associated, suggesting that increases in maternal Cortisol can influence Cortisol concentrations in the amniotic fluid and the foetus. In the studies on early postnatal maternal behaviour and child coping with stress, maternal sensitivity had different effects on child behavioural and Cortisol reactivity in response to stress across early childhood. For example, maternal behaviour had a direct influence on child behavioural and Cortisol reactivity to separation and novelty as well as recovery from distress however these effects were only observed children were two years old, and not when they were aged one or three years. Nevertheless, the results of the longitudinal study revealed that early maternal sensitivity can influence child behavioural and Cortisol distress reactivity when children are three years old. Children of more sensitive mothers were more reactive to separation and novelty. In addition, the longitudinal results revealed that maternal sensitivity and intrusiveness are not fixed and stable traits, but are behaviours that change over time and across different emotional states of the child during the course of early childhood. Collectively, the findings of this thesis demonstrate that small variations in prenatal stress and postnatal maternal behaviour in a normal low-risk sample can influence child temperament and coping with separation and novelty in early childhood. These findings indicate that a multi-method approach to studying maternal prenatal stress is necessary in order to obtain a better understanding of what aspects of prenatal stress are more important for child outcomes. In addition, the findings on the instability of maternal behaviour during early childhood highlight the importance of multiple assessments of sensitivity and intrusiveness in order to better capture maternal caregiving behaviour across time and its influence on child coping with stress

Influence of prenatal maternal stress, maternal plasma cortisol and cortisol in the amniotic fluid on birth outcomes and child temperament at 3 months

This prospective, longitudinal study aimed to investigate relationships between indicators of maternal prenatal stress, infant birth outcomes and early temperament. We examined the pattern of associations and postulated pathways between physiological (cortisol plasma concentrations) and self-report indices (stress, anxiety) of maternal prenatal stress, cortisol in the amniotic fluid, birth outcomes and infant temperament at 3 months. The sample consisted of 158 women undergoing amniocentesis in the 2nd trimester of pregnancy. Questionnaire measures of maternal stress and anxiety were found to be unrelated to cortisol in plasma or amniotic fluid. Maternal cortisol was related to amniotic cortisol, which in turn was associated with lower birth weight. Birth weight predicted infant fear and distress to limitation at 3 months old. We found trend-like indirect effects of amniotic fluid on infant distress to limitation and fear via birth weight. This is one of the few studies to simultaneously assess the role of maternal and amniotic fluid cortisol on birth outcomes and infant emotional development. The results suggest that foetal cortisol may be an important predictor of infant outcomes and shed light on the mechanisms through which prenatal maternal stress affects infant psychological health

Development of fear and guilt in young children: Stability over time and relations with psychopathology

Extremes in fearful temperament have long been associated with later psychopathology and risk pathways. Whereas fearful children are inhibited and anxious and avoid novel events, fearless individuals are disinhibited and more likely to engage in aggressive behavior. However, very few studies have examined fear in infants from a multimethod and prospective longitudinal perspective. This study had the following objectives: to examine behavioral, maternal reported, and physiological indices of fearful temperament in infancy, together with their relations and stability over time; and to establish whether early indices of fear predict fear later in toddlerhood. We also examined the association between behavioral and physiological measures of fear and guilt and whether fear in infancy predicts guilt in toddlers. Finally, we investigated infant risk factors for later psychopathology. We recorded skin conductance level (SCL) and heart rate (HR) and observed children's responses during a Laboratory Temperament Assessment Battery fear paradigm across the first 3 years of life and during a guilt induction procedure at age 3 (N = 70). The results indicate that different measures of infant fear were associated across time. Observed fearlessness in infancy predicted observed fearlessness and low levels of SCL arousal to fear and guilt in toddlers. Low levels of HR and SCL to fear in infancy predicted low levels of physiological arousal to the same situation and to guilt 2 years later. Fear and guilt were significantly associated across measures. Finally, toddlers with clinically significant internalizing problems at age 3 were already notably more fearful in Year 1 as reflected by their significantly higher HR levels. The results indicated that assessments of children in infancy are predictive of how these children react 2 years later and therefore lend support to the idea that the emotional thermostat is set in the first 3 years of life. They also showed, for the first time, that infant fear is a predictor of guilt, which is an emotion that develops later. The implications of these findings for our understanding of developmental psychopathology are discussed

Parental speech at 6 months predicts joint attention at 12 months

In a prospective longitudinal study of a representative community sample (N = 264), mothers' references to infants' mental states were coded during a topic-sharing task in the home at 6 months. Joint attention behaviour was assessed in the laboratory at 12 months. Individual joint attention skills (gaze following, gaze alternating, and declarative pointing) were significantly inter-correlated, with a single factor accounting for 68% of the variance. Mothers' references to infants' mental states at 6 months predicted infants' joint attention at 12 months. The association was not explained by sociodemographic characteristics of the family, the mother's mental state, or by the quantity or acoustic properties of her speech. However, variability in pitch of maternal speech was an independent predictor of the infants' later joint attention skills. Taken together, these findings suggest that mothers' infant-directed speech fosters infants' attentive participation in topic-sharing interactions, which in turn provide an important arena in which joint attention skills develop over the first year of life

Low skin conductance activity in infancy predicts aggression in toddlers 2 years later

Low autonomic nervous system activity is claimed to be a biomarker for aggressive and antisocial behavior. Although there is evidence that low skin conductance activity (SCA) accounts for variation in the severity of antisocial behavior and predicts the onset of aggression in children and adults, it is unknown whether SCA measured in infancy can predict the development of aggression. We measured SCA in 70 typically developing 1-year-old infants at baseline, during an orienting habituation paradigm, and during a fear challenge. We also observed the infants’ fear behavior, and each mother rated her infant’s temperament and her attachment to her child. At follow-up, mothers rated the children at 3 years old for aggressive and nonaggressive behavior problems. Low infant SCA predicted aggressive behavior, but there was no association between SCA and nonaggressive behavior problems. Mothers’ ratings of the infants’ temperament and their maternal attachment and the infants’ observed fearlessness did not predict later aggression. These results suggest that SCA is a specific biomarker for aggression in low-risk samples of infants

Influence of prenatal maternal stress, maternal plasma cortisol and cortisol in the amniotic fluid on birth outcomes and child temperament at 3 months

SummaryThis prospective, longitudinal study aimed to investigate relationships between indicators of maternal prenatal stress, infant birth outcomes and early temperament. We examined the pattern of associations and postulated pathways between physiological (cortisol plasma concentrations) and self-report indices (stress, anxiety) of maternal prenatal stress, cortisol in the amniotic fluid, birth outcomes and infant temperament at 3 months. The sample consisted of 158 women undergoing amniocentesis in the 2nd trimester of pregnancy. Questionnaire measures of maternal stress and anxiety were found to be unrelated to cortisol in plasma or amniotic fluid. Maternal cortisol was related to amniotic cortisol, which in turn was associated with lower birth weight. Birth weight predicted infant fear and distress to limitation at 3 months old. We found trend-like indirect effects of amniotic fluid on infant distress to limitation and fear via birth weight. This is one of the few studies to simultaneously assess the role of maternal and amniotic fluid cortisol on birth outcomes and infant emotional development. The results suggest that foetal cortisol may be an important predictor of infant outcomes and shed light on the mechanisms through which prenatal maternal stress affects infant psychological health