Executive function is associated with social competence in preschool-aged children born preterm or full term

Background

Executive function (EF), defined as higher-order cognitive processes used in planning and organizing actions and emotions, is often impaired in children born preterm. Few studies have assessed social competence, the processes and resources required to meet social demands and achieve social goals, in children born preterm. The relations between EF and social competence in preterm and full term preschoolers have not been well characterized.

Aims

To characterize social competence and assess the relationship between EF and social competence in preschool-aged children born preterm or full term.

Study design

Cross-sectional study.

Subjects

Study subjects had a history of preterm birth (≤ 34 weeks of gestation) and birth weight < 2500 g (n = 70). Controls were born full term (≥ 37 weeks) (n = 79).

Outcome measures

Children completed a battery of EF tasks; a mean age-adjusted z-score for the battery was generated for each child. Parents rated child EF on one scale and child social competence on two standardized scales.

Results

Compared to full term children, preterm children showed a lower mean EF battery z-score, poorer parent-rated EF, and poorer scores on the two social competence scales. In hierarchical multiple regression models, EF battery z-score and parent-rated EF made independent contributions to both measures of social competence. Preterm birth explained additional variance for one measure of social competence.

Conclusions

Standard assessment of EF skills and social competence in young preschool children, including children born preterm, may identify at-risk children for long-term social difficulties and may also provide targets for intervention.     

Cognitive development in very vs. moderately to late preterm and full-term children: Can effortful control account for group differences in toddlerhood?

Background

Preterm birth is thought to have an adverse impact on cognitive development and self-regulation.

Aim

Examining the effect of very vs. moderately to late premature birth on cognitive development and effortful control, as well as evaluating whether effortful control explains the link between preterm birth and poorer cognitive development.

Subjects

Fifty-eight very preterm children (< 32 weeks gestation or < 1500 g birth weight), 88 moderately to late preterm children (≥ 32 weeks gestation and ≥ 1500 birth weight) and 86 full-term children (≥ 38 weeks gestation and ≥ 2500 g birth weight) were examined at the corrected age of 24 months.

Outcome measures

Observational and parent-report measures of effortful control as well as the Bayley Scales of Infant Development II (BSID II, Mental Scale) as a measurement of cognitive development were analyzed.

Results

Very preterm and moderately to late preterm children showed significantly lower cognitive performance compared to full-term children. Lower effortful control scores (on observational measures, but not on parent-reports) were merely found for very preterm children compared to full-term children. Observational measures of effortful control partially mediated the effects of very preterm birth on cognitive performance, but did not explain the effects of moderately to late preterm birth on cognitive performance.

Conclusion

Preterm birth in general is related to poorer cognitive performance in toddlerhood. In addition, effortful control mediates the effects of very preterm birth on cognitive development. Findings suggest that different mechanisms link moderately to late premature birth to poor cognitive development.     

Behavior problems of 9-16 year old preterm children: biological, sociodemographic, and intellectual contributions

Background

Preterm children are at risk for behavior problems. Studies examining contributions of intellectual and environmental factors to behavior outcomes in preterm children are mixed.

Aims

(1) To identify the nature of maladaptive behaviors in preterm children age 9 to 16 years born across the spectrum of gestational age and birth weight (BW). (2) To examine contributions of BW as a biological factor, socioeconomic status as an environmental factor, and intelligence quotient (IQ) as indicative of intellectual ability to behavior outcomes.

Method

Using the Child Behavior Checklist, parent reports of behavior for 63 preterm children (gestational age 24 to < 36 weeks) were compared to 29 full term children of similar age, gender and socioeconomic status. Multiple regression models evaluated effects of prematurity, socioeconomic status, and intellectual ability on behavioral symptom scores.

Results

Preterm children had higher total and internalizing problem scores compared to full term children. They also had lower IQ. BW was a significant predictor of total and internalizing behavior problems. Among the syndrome scales, anxious/depressed and attention problems were elevated. Socioeconomic status did not contribute to behavior scores. IQ contributed to total, but not to internalizing or externalizing, scores. IQ contributed to attention problems, but not to anxious/depressed scores.

Conclusion

Preterm children had increased behavior problems, especially symptoms of inattention and anxiety. Lower BW predicted more behavior problems. IQ acted as a mediator between BW and attention scores, but not anxiety scores. These findings alert health care providers to assess anxiety in all preterm children regardless of intellectual ability and additional study on the influence of intellectual ability on behavioral outcomes in preterm children is needed.     

Association of complex lipids containing gangliosides with cognitive development of 6-month-old infants

Background

Human breastmilk contains gangliosides which may play an important role in infant neurodevelopment.

Aim

A pilot study was conducted to assess the impact of infant formula supplemented with gangliosides from complex milk lipid on cognitive functions of normal healthy infants.

Study design

The study was a double-blind, randomized, controlled, parallel group clinical trial in which infants received the treatment or control product from 2 to 8 weeks of age until 24 weeks of age. The control group (n = 30) received standard infant formula and the treatment group (n = 29) received the same formula supplemented with complex milk lipid to increase the ganglioside content to approximately 11 to 12 μg/ml. A reference group (n = 32) consisted of normal healthy exclusively breast-fed infants.

Outcome measures

Cognitive development using the Griffith Scales and serum gangliosides was measured before (2–8 weeks of age) and after intervention (24 weeks of age).

Results

Ganglioside supplementation using complex milk lipids significantly increased ganglioside serum levels (control group vs treatment group, P = 0.002) and resulted in increased scores for Hand and Eye coordination IQ (P < 0.006), Performance IQ (P < 0.001) and General IQ (P = 0.041). Cognitive development scores and serum ganglioside levels for the treatment group did not differ from the reference group.

Conclusions

Supplementation of infant formula with complex milk lipid to enhance ganglioside content appears to have beneficial effects on cognitive development in healthy infants aged 0–6 months, which may be related to increased serum ganglioside levels.     

Prevalence and predictors of idiopathic asymmetry in infants born preterm

Background

An idiopathic asymmetry in posture of the head is recognized as a risk factor to develop a deformational plagiocephaly (DP). In our neonatal follow-up clinic, an IA is often observed in infants born preterm at term-equivalent age (TEA).

Aims

To explore (1) the prevalence of an idiopathic asymmetry in 192 infants (gestational age ≤ 32.0 weeks) at TEA and 6 months corrected age (CA), (2) whether demographical, perinatal, and medical factors were predictors of the asymmetry, and (3) differences in motor maturation between infants with and without asymmetry.

Methods

In a retrospective study, frequencies of idiopathic asymmetry and DP, putative predictors, and Alberta Infant Motor Scale scores at 6 months CA were abstracted and analyzed with Chi², Mann–Whitney, logistic regression and T-test.

Results

The prevalence rate of a positional preference of the head at TEA was 44.8% (n = 86), 10.4% (20/192) had a DP at TEA and 13% (25/192) at 6 months CA. Positional preference, multiple birth and male gender predicted the presence of DP (p < .05, odds ratio 3.0, 3.2, and 3.1 respectively). Gross motor maturity at 6 months CA was less developed in infants with a positional preference at TEA compared to preterm norms (p = 0.01).

Conclusions

The high prevalence of a positional preference in infants born preterm at term equivalent age requires extra alertness to prevent the development of a deformational plagiocephaly, especially in boys and twins. Although, considering the lower prevalence of plagiocephaly at 6 months CA, therapists should be aware of over treating these infants.     

Change in cognitive abilities over time during preschool age in low risk preterm children

Background

More information is needed on ‘low-risk’ preterm infants' neurological outcome so that they can be included in follow-up programs at least until school age.

Objective

To examine the neuropsychological outcome in a group of low-risk low birth weight (LBW) children without neurological impairment followed from birth to 5 years of age.

Patients

26 intellectually normal children born preterm (30–34 weeks gestation) without major neurological disabilities and 23 control children born at term and matched for age, sex, and parental educational and occupational status.

Methods

Subjects already evaluated at 3 years of age underwent assessment again at 5 years using as neuropsychological outcome measures a wide range of tests including perceptual and visual–motor function, language comprehension and expression, and attention skills.

Results

When tested at 5 years, children born preterm still obtained significantly lower mean scores than controls on visual motor integration test (57 vs 64, p = 0.01), visual perception test (41 vs 43, p = 0.002) and a trend toward a lower score in the picture vocabulary test (81 vs 85.5, p = 0.07). The group of premature infants and controls improved their performance over time in the neuropsychological abilities investigated and, in some skills such as visual perception. Children born preterm took longer than those born at term to reach similar performance levels, 5 versus 3 years.

Conclusion

Ex low-risk children born preterm achieve lower scores over time in visual–motor and perceptual ability scales and in some language tests than children born at term. Like high-risk premature infants even those at low risk deserve regular follow-up with long-term programs.     

Oral and nonoral sensorimotor interventions facilitate suck-swallow-respiration functions and their coordination in preterm infants

Background

Preterm infants are at high risk of encountering oral feeding difficulties. Early sensorimotor interventions may improve oral feeding skills in preterm infants.

Aim

To further explore the effects of an oral (O), tactile/kinesthetic (T/K), and combined (O + T/K) sensorimotor intervention on preterm infants' nutritive sucking, swallowing and their coordination with respiration.

Study design

Seventy-five infants (29 [0.3, standard error of mean, SEM] weeks gestation, 49 males/26 females) were randomly assigned to an O group involving sensorimotor input to the oral structures; a T/K group involving sensorimotor input to the trunk and limbs; a combined (O + T/K) group; and a control group.

Outcome measures

Stage of sucking, suction and expression amplitudes (mm Hg), suck–swallow ratio, stability of suck–swallow interval, and swallow–respiration patterns.

Results

The O group had significantly more advanced sucking stages, and greater suction and expression amplitudes than controls [p ≤ 0.035, effect size (ES) > 0.6]. The suck–swallow ratio and stability of suck–swallow intervals did not significantly differ among groups (p ≥ 0.181, ES ≤ 0.3). The three interventions led to fewer swallows bracketed by prolonged respiratory pauses compared to controls (pause–swallow–pause, p ≤ 0.044, ES ≥ 0.7). The T/K and combined (O + T/K) groups had greater occurrence of swallows bracketed by expiration than the control and O groups (expiration–swallow–expiration, p ≤ 0.039, ES ≥ 0.3).

Conclusion

The O intervention enhanced specific components of nutritive sucking. All three interventions resulted in improved swallow–respiration coordination. Sensorimotor interventions have distributed beneficial effects that go beyond the specific target of input.     

Entorhinal cortical thinning affects perceptual and cognitive functions in adolescents born preterm with very low birth weight (VLBW)

Background

The entorhinal cortex serves as an important gateway between the cerebral cortex and the hippocampus by receiving afferent information from limbic, modality sensory-specific, and multimodal association fibers from all the brain lobes.

Aim

To investigate whether thinning of entorhinal cortex is associated with reduced perceptual, cognitive and executive skills in very low birth weight (VLBW) adolescents.

Study design

Prospective, geographically based follow-up study of three year cohorts of preterm born VLBW children.

Subjects

Forty-nine VLBW (birth weight ≤ 1500 g) and 58 term-born control adolescents were examined at the age of 14–15 years.

Outcome measures

Perceptual and cognitive functions were assessed with Visual motor integration test, Grooved Pegboard test, Wechsler Intelligence Scale for Children-III and different executive function tests (Wisconsin card sorting test, Trail Making test, Knox cube test). An automated MRI technique at 1.5 T for morphometric analyses of cortical thickness was performed. Areas with cortical thinning in left and right entorhinal cortex in the VLBW group were chosen as regions of interest to look for associations between cortical thickness and clinical findings.

Results

Thinning of the entorhinal cortex was correlated with low performance on perceptual and cognitive scores in the VLBW adolescents, but not in controls. In addition, thinning of the entorhinal cortices correlated with reduced performance on several executive tests, including perceptual speed and aspects of working memory.

Conclusions

Entorhinal cortical thinning is related with low IQ and reduced perceptual and executive functions in VLBW adolescents.     

The use of oxygen for delivery room resuscitation of newborn infants in non-Western countries

Background

Using pure oxygen (PO) in neonatal resuscitation increases oxidative stress and mortality in full-term hypoxic infants. International neonatal resuscitation guidelines recommend air or blended oxygen for resuscitation regardless of gestational age but this requires education and equipment that may not be globally available.

Objective

To determine current neonatal resuscitation practices and availability of oxygen blending equipment in non-Western hospitals.

Design

196 email addresses were obtained through perinatal societies representing 45 hospitals in 14 countries in Asia, Africa and the Middle East.

Results

68 (34.6%) responses were received from all 14 countries. The majority (90%, n = 61) of respondents were aware of recent guideline changes but continued to resuscitate with PO because of the lack of equipment and uncertainty about international guidelines (61%, n = 41 for term, 44%, n = 30 for preterm). Most (81%, n = 55) believed that PO caused adverse effects in term neonates. The availability of oxygen blending equipment correlated significantly with the country's gross domestic product.

Conclusion

The majority of the practitioners we surveyed in non-Western countries are aware of the most recent recommendations regarding oxygen use in neonatal resuscitation. However, lack of oxygen blending equipment remains a hindrance to the use of blended gas at resuscitation in low resource, non-western countries. Global guidelines from developed countries must take into account the resource limitations and implementation difficulties faced by countries with restricted resources, where the majority of the high-risk infants are born.     

Maternal consumption of a DHA-containing functional food benefits infant sleep patterning: an early neurodevelopmental measure

Background

Docosahexaenoic acid (DHA; 22:6n − 3) is highly important during pregnancy for optimal development and functioning of fetal neural tissue. Infant ability to organize sleep and wake states following parturition is highly associated with later developmental outcomes. The impact of maternal DHA intake on sleep organization has not been previously investigated.

Aims

To examine the effect of a DHA-containing functional food consumed during pregnancy on early neurobehavioral development as assessed by infant sleep patterning in the first 48 postnatal hours.

Study design

A longitudinal, randomized, double-blinded, placebo-controlled design was used.

Subjects

Women (18–35 y) with no pregnancy complications consumed a cereal-based functional food (92 kcal) containing 300 mg DHA an average of 5 d/week or placebo bars (n = 27 DHA, n = 21 Placebo). The intervention began at 24 weeks gestation and continued until delivery (38–40 weeks).

Outcome measures

Infant sleep/wake states were measured on postnatal days 1 (D1) and 2 (D2) using a pressure sensitive mattress recording respiration and body movements.

Results

Using ANCOVA and controlling for ethnic variation, there were significant group differences in arousals in quiet sleep on D1 (P = 0.006) and D2 (P = 0.011) with fewer arousals in the DHA intervention group compared to the placebo group. Similarly, arousals in active sleep on D1 were significantly lower in the DHA-intervention group (P = 0.012) compared to the placebo group.

Conclusions

We conclude that increased prenatal supply of dietary DHA has a beneficial impact on infant sleep organization.     

Emotional and effortful control abilities in 42-month-old very preterm and full-term children

Background

Very preterm (VP) infants are at greater risk for cognitive difficulties that may persist during school-age, adolescence and adulthood. Behavioral assessments report either effortful control (part of executive functions) or emotional reactivity/regulation impairments.

Aims

The aim of this study is to examine whether emotional recognition, reactivity, and regulation, as well as effortful control abilities are impaired in very preterm children at 42 months of age, compared with their full-term peers, and to what extent emotional and effortful control difficulties are linked.

Study design

Children born very preterm (VP; < 29 weeks gestational age, n = 41) and full-term (FT) aged-matched children (n = 47) participated in a series of specific neuropsychological tests assessing their level of emotional understanding, reactivity and regulation, as well as their attentional and effortful control abilities.

Results

VP children exhibited higher scores of frustration and fear, and were less accurate in naming facial expressions of emotions than their aged-matched peers. However, VP children and FT children equally performed when asked to choose emotional facial expression in social context, and when we assessed their selective attention skills. VP performed significantly lower than full terms on two tasks of inhibition when correcting for verbal skills. Moreover, significant correlations between cognitive capacities (effortful control) and emotional abilities were evidenced.

Conclusions

Compared to their FT peers, 42 month-olds who were born very preterm are at higher risk of exhibiting specific emotional and effortful control difficulties. The results suggest that these difficulties are linked. Ongoing behavioral and emotional impairments starting at an early age in preterms highlight the need for early interventions based on a better understanding of the relationship between emotional and cognitive difficulties.     

Cerebral palsy in children: Movements and postures during early infancy, dependent on preterm vs. full term birth

Background

A deviant motor behaviour at age 3 to 5 months is predictive of cerebral palsy (CP). Particular features of the early motor repertoire even proved predictive of the degree of functional limitations as classified on the Gross Motor Function Classification System (GMFCS) in children with CP, born preterm.

Aims

We aimed to determine whether an association between the early motor repertoire and the GMFCS also holds true for children born at term.

Study design

Longitudinal study.

Subjects

79 infants (60 boys and 19 girls; 47 infants born at term; video recorded for the assessment of movements and posture at age 9 to 20 weeks postterm age) who developed CP.

Outcome measures

The GMFCS was applied at age 2 to 5 years.

Results

Motor optimality at age 3 to 5 months showed a significant correlation with functional mobility and activity limitation as classified on the GMFCS at age 2 to 5 years in both children born at term (Spearman rho = − 0.66, p < 0.001) and born preterm (rho = − 0.37, p < 0.05). Infants born preterm were more likely to show normal movement patterns than infants born at term. A normal posture and an abnormal, jerky (yet not monotonous) movement character resulted in better levels of function and mobility. With the exception of one, none of the infants showed fidgety movements. A cramped-synchronised movement character, repetitive opening and closing of the mouth, and abnormal finger postures characterised children who would show a poor self-mobility later.

Conclusions

Assessing the quality of motor performance at 9 to 20 weeks postterm age (irrespective of the gestational age) improves our ability to predict later functional limitations in children with CP.     

Basic numerical processes in very preterm children: A critical transition from preschool to school age

Background

Serious difficulties in formal mathematical skills have been identified in preterm children. By contrast, basic-level numerical skills like magnitude judgments have not yet been tested in these children.

Aims

The aim of the present research was to investigate whether preterm birth also affects these basic numerical abilities, with particular attention to the transition from preschool to formal education.

Method

One hundred-forty very preterm children and 60 age-matched controls were recruited in a cross-sectional study at 6 and 8 years of age. Magnitude comparison tasks with non-symbolic dot displays or symbolic Arabic-number stimuli, measuring accuracy and reaction time, were administered to participants. We also investigated explicit number knowledge, as well as general cognitive developmental levels, to gain a broader picture of preterm abilities.

Results

Despite no general cognitive delay, the more simple approximate non-symbolic representation of numerical magnitude was affected by preterm birth, with slower reaction times at both ages compared to controls. Additionally, clear difficulties in the construction of the symbolic representation of numerical magnitude and in explicit number knowledge emerged in the 6-year-old preterm children, with a recovery from this serious delay finally by 8 years.

Conclusions

The serious delays identified here in basic numerical abilities in preterm children, despite normal IQ, point to the need for further studies in order to elucidate the relationship between basic numerical abilities and subsequent difficulties in formal mathematic achievement at school.     

Cord blood 8-isoprostane in the preterm infant

Background

Cord blood 8-isoprostane (8-IP) is a marker of lipid peroxidation in the peripartum period. The independent association with degree of prematurity is not well-described.

Objective

To identify patterns of lipid peroxidation among early, moderate and late preterm infants, and to understand how cord blood 8-IP varies with gestational age (GA) and related covariates.

Study design

Mother–infant pairs from 237 preterm births were studied as part of a longitudinal birth cohort study. GA subgroups were defined as extremely (≤ 28w), moderately (29–33w), and late (34–36w) preterm. Cord blood 8-IP was measured using EIA. Elevated 8-IP (4th quartile) was the primary outcome for multivariate logistic regression models, which were adjusted for maternal age/race, multiple gestation and infant gender, as well as other relevant covariates.

Results

Elevated 8-IP was associated with extremely preterm birth (OR = 4.31; 95% CI = 1.90, 9.76), and was inversely associated with increasing GA (OR = 0.88; 95% CI = 0.80, 0.97). Elevated 8-IP was also associated with decreasing birth weight (BW), clinical chorioamnionitis, fetal inflammatory response of the placenta (FIR), and signs of perinatal depression. The GA on 8-IP association appeared to be modified by several maternal disease and fetal–infant factors. Lastly, the indirect associations between log-transformed 8-IP, GA and BW appeared to be most prominent for GA < 30w and for BW < 2000 g.

Conclusion

Lipid peroxidation in preterm birth, and the relative influence of accompanying peripartum factors, varies according to degree of prematurity. These findings have important implications for the developmental regulation of antioxidant defense and its impact on neonatal outcomes.     

Outcomes of extremely low birth weight infants with bronchopulmonary dysplasia: impact of the physiologic definition

Aims

We compared neurodevelopmental outcomes of extremely low birth weight (ELBW) infants with and without bronchopulmonary dysplasia (BPD), using the physiologic definition.

Study design

ELBW (birth weights < 1000 g) infants admitted to the Neonatal Research Network centers and hospitalized at 36 weeks postmenstrual age (n = 1189) were classified using the physiologic definition of BPD. Infants underwent Bayley III assessment at 18–22 months corrected age. Multivariable logistic regression was used to determine the association between physiologic BPD and cognitive impairment (score < 70).

Results

BPD by the physiologic definition was diagnosed in 603 (52%) infants, 537 of whom were mechanically ventilated or on FiO₂ > 30% and 66 who failed the room air challenge. Infants on room air (n = 505) and those who passed the room air challenge (n = 51) were classified as “no BPD” (n = 556). At follow up, infants with BPD had significantly lower mean weight and head circumference. Moderate to severe cerebral palsy (7 vs. 2.1%) and spastic diplegia (7.8 vs. 4.1%) and quadriplegia (3.9 vs. 0.9%) phenotypes as well as cognitive (12.8 vs. 4.6%) and language scores < 70 (24.2 vs. 12.3%) were significantly more frequent in those with BPD compared to those without BPD. BPD was independently associated (adjusted OR 2.4; 95% CI 1.40–4.13) with cognitive impairment.

Conclusions

Rates of adverse neurodevelopmental outcomes in early childhood were significantly higher in those with BPD. BPD by the physiologic definition was independently associated with cognitive impairment using Bayley Scales III. These findings have implications for targeted post-discharge surveillance and early intervention.     

Differential associations between maternal scaffolding and toddler emotion regulation in toddlers born preterm and full term

Background

Parental “scaffolding” behavior has been associated with developmental outcomes in at-risk children.

Aims

Because there are limited empirical data regarding how scaffolding is associated with emotion-based developmental skills, the purpose of this study was to compare associations between maternal verbal scaffolding and toddler emotion regulation, including fewer displays of negative affect and increased contentment and enjoyment during play, in toddlers born preterm and full term.

Study design

This study was a cross-sectional cohort design. Maternal and toddler behavior was assessed during 5 min of videotaped free play with standardized toys.

Subjects

131 toddlers (18–22 months) and their mothers were included (77 born preterm; 54 born full term).

Outcome measures

Toddler emotion regulation, negative affect, and dyadic mutual enjoyment were coded from videotaped play.

Results

The association between maternal scaffolding and emotion regulation was different for dyads with a toddler born preterm versus full term, wherein the association was positive for toddlers born preterm and non-significant for toddlers born full term. Similarly, the association between maternal scaffolding and negative affect was different for the two groups: negative for toddlers born preterm and non-significant for toddlers born full term. Finally, the association between maternal scaffolding and mutual enjoyment was positive for toddlers born preterm and non-significant for toddlers born full term.

Conclusions

Our findings highlight early differences in mother-child interactive style correlates of children born preterm compared to those born full term. Maternal scaffolding behavior may be uniquely associated with emotion regulation and a positive dyadic encounter for toddlers born preterm.     

Bullying of extremely low birth weight children: Associated risk factors during adolescence

Background

Preterm children have many risk factors which may increase their susceptibility to being bullied.

Aims

To examine the prevalence of bullying among extremely low birth weight (ELBW, < 1 kg) and normal birth weight (NBW) adolescents and the associated sociodemographic, physical, and psychosocial risk factors and correlates among the ELBW children.

Methods

Cohort study of self-reports of bullying among 172 ELBW adolescents born 1992–1995 compared to 115 NBW adolescents of similar age, sex and sociodemographic status. Reports of being bullied were documented using the KIDSCREEN-52 Questionnaire which includes three Likert type questions concerning social acceptance and bullying. Multiple linear regression analyses adjusting for sociodemographic factors were used to examine the correlates of bullying among the ELBW children.

Results

Group differences revealed a non-significant trend of higher mean bullying scores among ELBW vs. NBW children (1.56 vs. 1.16, p = 0.057). ELBW boys had significantly higher bullying scores than NBW boys (1.94 vs. 0.91, p < 0.01), whereas ELBW and NBW girls did not differ (1.34 vs. 1.30, p = 0.58). Bullying of ELBW children was significantly associated with subnormal IQ, functional limitations, anxiety and ADHD, poor school connectedness, less peer connectedness, less satisfaction with health and comfort, and less risk avoidance.

Conclusion

ELBW boys, but not girls, are more likely to be victims of bullying than NBW boys. School and health professionals need to be aware of the risk of bullying among ELBW male adolescents.     

Thermal detection thresholds in 5-year-old preterm born children; IQ does matter

Background

Experiencing pain at newborn age may have consequences on one's somatosensory perception later in life. Children's perception for cold and warm stimuli may be determined with the Thermal Sensory Analyzer (TSA) device by two different methods.

Aim

This pilot study in 5-year-old children born preterm aimed at establishing whether the TSA method of limits, which is dependent of reaction time, and the method of levels, which is independent of reaction time, would yield different cold and warm detection thresholds. The second aim was to establish possible associations between intellectual ability and the detection thresholds obtained with either method.

Study design

A convenience sample was drawn from the participants in an ongoing 5-year follow-up study of a randomized controlled trial on effects of morphine during mechanical ventilation.

Methods

Thresholds were assessed using both methods and statistically compared. Possible associations between the child's intelligence quotient (IQ) and threshold levels were analyzed.

Results

The method of levels yielded more sensitive thresholds than did the method of limits, i.e. mean (SD) cold detection thresholds: 30.3 (1.4) versus 28.4 (1.7) (Cohen's d = 1.2, P = 0.001) and warm detection thresholds; 33.9 (1.9) versus 35.6 (2.1) (Cohen's d = 0.8, P = 0.04). IQ was statistically significantly associated only with the detection thresholds obtained with the method of limits (cold: r = 0.64, warm: r = − 0.52).

Discussion

The TSA method of levels, is to be preferred over the method of limits in 5-year-old preterm born children, as it establishes more sensitive detection thresholds and is independent of IQ.     

Fetal habituation in assisted conception

Background

Neurodevelopment outcomes of children conceived by Assisted Reproductive Technology (ART)have been the subject of much recent attention. To date there are no reports of neurodevelopmental performance before birth in this group.

Aims

To compare habituation (a measure of brain function) in fetuses conceived by assisted reproduction techniques (ART) with naturally conceived (NC) fetuses.

Study design

Case control study.

Subjects

Women with singleton pregnancies matched for maternal age, parity and smoking were recruited in 2 groups: ART (n = 20) and NC (n = 20).

Outcome measures

Sound stimuli (250 Hz, 110 dB) at 10 second intervals lasting 2 s were administered to the fetus. The end point was habituation (cessation of movement for five consecutive stimuli) or a maximum of 30 stimuli. Responses of the fetus were observed with ultrasound at 28, 32 and 36 weeks' gestation, video-recorded and anonymised for analysis.

Results

At 28 weeks' gestation significantly more ART fetuses responded to sound of 250 Hz, 110 dB (p = 0.02) but this difference did not persist at 32 and 36 weeks'. There was a significant increase in nonresponders as gestation advanced in the ART group. There was no difference in habituation or mean number of trials to habituate at all three gestations.

Conclusions

ART fetuses demonstrated no differences in habituation suggesting that there is no neurodevelopment delay. However, a decrease in response to sound as gestation advances might be a harbinger for poor perinatal outcomes and needs exploration.     

Fetal myocardial tissue Doppler indices before birth physiologically change in proportion to body size adjusted for gestational age in low-risk term pregnancies

Background

Few studies have investigated the relationship between myocardial tissue Doppler parameters and fetal size adjusted for gestational age and its trend has been controversial.

Aims

To investigate fetal cardiac function before birth using tissue Doppler imaging (TDI: indicated by the prime symbol (′)) in low-risk term pregnancies by comparing the TDI parameters with gestational age-specific birth weight percentiles and z scores.Study design and measurementsInterventricular septum, left and right ventricular myocardial peak early diastolic (E′), late diastolic (A′) and systolic (S′) velocities, E′/A′ ratios, myocardial performance index (MPI′) and umbilical artery pulsatility index were measured within three days before birth in 76 low-risk term pregnancies, including appropriate for gestational age (AGA, n = 50), small for gestational age (SGA, n = 10), and large for gestational age (LGA, n = 16) subjects.

Results

Myocardial peak velocities showed higher in the LGA and lower in the SGA compared with the AGA group, and All S′ positively correlated with birth weight (r = 0.51–0.57). All z scores of S′ demonstrated a positive correlation with birth weight z score (Spearman r = 0.45–0.53). MPI′ was significantly higher in the SGA and lower in the LGA compared with the AGA group. All MPI′ negatively correlated with birth weight (r = − 0.55 to − 0.65). All z scores of MPI′ showed a negative correlation with birth weight z score (Spearman r = − 0.40 to − 0.56).

Conclusions

Fetal myocardial peak velocities and MPI′ physiologically changed in proportion to body size adjusted for gestational age in low-risk term pregnancies.