Low Birth Weight Boys Research Articles

Impact of low birth weight on academic attainment during adolescence: A comprehensive retrospective cohort study using linked data

BackgroundThis study addresses a critical knowledge gap by exploring the intricate relationship between low birth weight (LBW) and the heightened risk of suboptimal academic achievement during adolescence through a comprehensive retrospective cohort design. MethodsIn this registry-based cohort study, meticulously linked health and curriculum-based test data for individuals born in New South Wales (NSW), Australia, between 2003 and 2005 were employed. Birth weight data were carefully sourced from the NSW perinatal data collection (PDC). The educational performance of offspring was thoroughly evaluated using the National Assessment Program for Literacy and Numeracy (NAPLAN) during grade 9, approximately at 14 years of age. ResultsAfter rigorous adjustments for potential confounders, findings revealed a compelling narrative: LBW adolescents demonstrated an elevated susceptibility to not meeting national minimum standards across all domains, encompassing spelling [OR, 1.59 (95%CI 1.48–1.69)], writing [OR, 1.51 (95%CI 1.41–1.61)], reading [OR, 1.38 (95%CI 1.29–1.48)], and numeracy [OR, 1.52 (95%CI 1.40–1.63)]. Notably, LBW boys exhibited a more pronounced inclination towards diminished academic performance compared to their female counterparts. ConclusionsThis comprehensive retrospective cohort study, based on linked data, unequivocally establishes LBW as significantly associated with an increased vulnerability to substandard educational achievement during adolescence. Particularly robust effects were observed in females across all outcomes. Aimed at investigating whether LBW serves as a predictive factor for later academic difficulties, this study underscores the imperative for the adoption and fortification of preventative and early intervention strategies to curtail the prevalence of LBW-associated academic underachievement in later adolescence.

Longitudinal Sex Steroid Data in Relation to Birth Weight in Preterm Boys.

There is a lack of knowledge on longitudinal sex steroid patterns during infancy, especially for boys born preterm or with low birth weight (LBW). To find out whether LBW boys have a disturbed sex steroid profile during infancy. Population-based longitudinal study performed at Sahlgrenska University Hospital, Gothenburg, Sweden. Ninety-eight singleton boys (47 LBW) born at gestational age 32.0 to 36.9 weeks were included. Because of dropout, 83 of the boys were still in the study at 10 months' corrected age. Serum androgen and estrogen concentrations were analyzed by gas chromatography-tandem mass spectrometry and IGF-I was determined with radioimmunoassay in umbilical cord and at 0, 2, 5, and 10 months' corrected age. Serum levels of androstenedione, estrone, and estradiol declined gradually from birth to 10 months corrected age. In both LBW boys and their counterparts, a surge was seen at 2 months' corrected age (3 months' chronological age) for testosterone, median (range) 6.5 (2.0-18.9) nmol/L, and in dihydrotestosterone 1.2 (0.4-4.3) nmol/L. At birth, LBW boys had higher median testosterone (0.7 vs 0.4 nmol/L, P = 0.019), and at 0 months' corrected age, both had higher testosterone (5.7 vs 3.5 nmol/L, P = 0.003) and dihydrotestosterone (1.2 vs 0.9 nmol/L, P = 0.006) than their counterparts. At 10 months' corrected age, catch-up in weight SD score from birth correlated with testosterone (rho = 0.27, P = 0.044) and androstenedione (rho = 0.29, P = 0.027). Moderately to late preterm LBW boys showed a disturbed sex hormone profile, with elevated concentrations of androgens in early infancy.

Rapid Protective Effects of Early BCG on Neonatal Mortality Among Low Birth Weight Boys: Observations From Randomized Trials.

Three randomized trials (RCTs) in low-weight (<2.5 kg) infants have shown that Bacille Calmette-Guérin (BCG) vaccine nonspecifically reduces all-cause mortality in the neonatal period. Using data from 3 RCTs of early BCG (n = 6583) we examined potential sex differences in the timing of the mortality reduction in the neonatal period, presenting metaestimates of the main outcome mortality rate ratios (MRR) for BCG-vaccinated and controls. Among controls, boys had a particularly high mortality during the first week after randomization: male-female MRR 2.71 (95% CI, 1.70-4.50). During the first week, BCG had a marked beneficial effect for boys, reducing mortality 3-fold (MRR [BCG/no BCG] = 0.36 [0.20-0.67]). In weeks 2-4 the effect waned for boys (MRR = 0.91 [0.51-1.69]). In girls, the pattern was opposite with a limited effect in the first week (MRR = 0.85 [0.46-1.54]), but a significant reduction in weeks 2-4 (MRR = 0.56 [0.31-1.00]). This was consistent in all 3 trials. Verbal autopsies linked early benefit to fewer sepsis-related deaths among BCG-vaccinated boys. The marked reduction in mortality in the days after BCG vaccination in boys emphasizes the importance of providing BCG soon after birth. ClinicalTrials.gov (NCT00146302) and ClinicalTrials.gov (NCT00625482).

Shorter anogenital distance correlates with undescended testis: a detailed genital anthropometric analysis in human newborns

Are the anogenital distance (AGD) and stretched penile length (SPL) shorter in human newborn males with cryptorchidism? AGD is significantly shorter in boys with undescended testis (UDT) and this correlation may indicate that both have a common antecedent early in gestation. Animal studies have reported a critical time period during early gestation termed the male programming window (MPW) where androgen deficiency results in reduced AGD and penile length, as well as cryptorchidism and hypospadias. Two pilot human studies have explored this association but these studies were small and heterogeneous with regard to age, race and had selection bias. A prospective descriptive study involving measurement of AGD and SPL at birth in a racially homogenous sample of 1154 consecutive newborns was performed over a period of 6 months. All measurements were taken by a single trained observer (V.J.). All consecutively born male infants at a community hospital were classified as having descended and or UDT. Testicular position in the undescended group was graded as high scrotal, inguinal or non-palpable. AGD (from the centre of anus to the junction of the smooth and rugated skin of scrotum) and SPL were measured. The AGD index (AGDi) was calculated by dividing AGD by cube root of birthweight. Of the 1154 infants examined, 624 were males and 71 had UDT. AGD was significantly shorter in infants with UDT when compared with infants with descended testis (mean ± SD; 2.21 ± 0.36 versus 2.56 ± 0.31 cm; P < 0.001). AGDi was also significantly shorter in infants with UDT (mean ± SD; 1.68 ± 0.27 versus 1.81 ± 0.20 cm/kg⁻³; P < 0.001). Significance was maintained even when preterm (P < 0.001) and low birthweight boys (LBW) (P < 0.001) were excluded. SPL was also significantly shorter in infants with UDT (Mean ± SD; 3.08 ± 0.52 versus 3.31 ± 0.38 cm; P < 0.001) but the significance was not maintained when preterm (P = 0.119) and LBW boys (P = 0.666) were excluded. Birthweight, gestational age and length adjusted regression models showed significantly shorter AGD in infants with UDT, but SPL was not different. Infants with higher position of testis appeared to have a shorter AGD and SPL but the correlation did not reach statistical significance. No difference in AGD or SPL was noted between boys with unilateral and bilateral UDT. The present study did not include data pertaining to maternal or newborn health status. Also parental drug exposure or occupational exposures to endocrine-disrupting chemicals was not studied. These may possibly affect genital anthropometric measurements. The study strengthens the hypothesis of existence of MPW in humans. Shorter AGD in cryptorchid infants may reflect the effect of androgen disruption or deficiency during MPW. AGD may be a more reliable non-invasive marker of androgen action during MPW than SPL to predict reproductive outcomes in humans.

Does parent education moderate relations between low birth weight and child cognitive development outcomes?

Using baseline and 3-year data from The Fragile Families and Child Wellbeing Study, we examined the potential for mothers' and fathers' education to buffer at-risk and low birth weight (LBW) children from poor cognitive development outcomes at age 3. Findings suggest that mothers' and fathers' education may both buffer at-risk children from poor cognitive development outcomes, although in different ways. Whereas fathers' education was associated with better cognitive development among LBW boys, mothers' education was associated with better cognitive development among normal birth weight children, regardless of child gender. We further examined whether parent involvement mediated the relation between parent education and child cognitive development. After controlling for demographic variables and our variables of interest we found no significant associations between parent involvement and child cognitive development. Results suggest that other pathways, such as the development of financial and material cap...

A comparative study of sanitary napkins and absorbent nappy pads for urine output measurement in neonates

To compare sanitary napkins and absorbent nappy pads (ANP) for urine output (UO) measurement. Phase 1: Freshly passed neonatal urine (5, 10 and 15 mL) was poured onto preweighed sanitary napkins or ANP, which were juxtaposed to the genital area of manikins placed in incubators/warmers and weighed at (1/2), 1, 2, 4, 5 and 6 hr. Outcome was percentage weight change from baseline. Phase 2: Five very low birth weight boys in incubators had UO measurement by test tubes. A sanitary napkin or ANP was co-applied with the test tube for 4 h each. Urine collected in the test tube was measured and poured on the device, which was reapplied. Weight and wetness were checked. Phase 1: Mean urine loss was 8.35, 13.8, 20.1, 25.2, 33.1, 38.7 and 42.6% at (1/2), 1, 2, 3, 4, 5 and 6 h, respectively (repeated measures ANOVA [RM-ANOVA], p < 0.001). Loss was higher with ANP than sanitary napkins (32.1% vs. 13.4%, two-way RM-ANOVA, p = 0.001). There was less loss in incubators versus radiant warmers at 6 h (p = 0.09). Phase 2: There was 12.1 and 26% deficit with sanitary napkin and ANP, respectively. Wetness was felt in one and four cases, respectively. Urinary losses are less from sanitary napkins than ANPs.

Weight Concerns in Male Low Birth Weight Adolescents: Relation to Body Mass Index, Self-Esteem, and Depression

To compare weight concerns and self-reported body mass index (BMI) of low birth weight (LBW) adolescent boys to those of a normative sample and examine relationships among BMI, weight concerns, self-esteem, and depression in the LBW cohort. LBW boys (n = 260; mean age, 16.0) belong to the Neonatal Brain Hemorrhage Study birth cohort. Normative boys (n = 305; mean age, 16.5) belong to the National Health and Nutrition Examination Survey. Both samples were assessed in 2001-2004 with self-report questionnaires. BMI was calculated from self-reported height and weight. Weight perception and weight dissatisfaction were assessed with the Eating Symptoms Inventory. In LBW boys, self-esteem was measured with the Rosenberg Self-Esteem Scale and depression with the Beck Depression Inventory. Based on self-reported height and weight, LBW boys were more likely to be healthy weight or underweight and less likely to be overweight than normative boys. Despite having healthier self-reported BMIs, LBW boys reported more weight concerns than the normative sample. A total of 46.9% of LBW boys perceived their weight as abnormal, and 76.5% desired weight change. Weight concerns in LBW boys mostly reflected a perception of being underweight (31.2% of the cohort) and a desire to gain weight (47.5% of the cohort), although only 6.5% were clinically underweight. Weight concerns, but not BMI, were related to clinical depression and lower self-esteem. LBW adolescent boys are at high risk of experiencing weight concerns. Weight concerns rather than BMI are associated with emotional problems in LBW boys.

Birth Weight and Gestational Age Characteristics of Children With Autism, Including a Comparison With Other Developmental Disabilities

The objectives of this study were to compare the birth weight and gestational age distributions and prevalence rates of autism with those of other developmental disabilities and to estimate the birth weight-and gestational age-specific risks for autism. For the first objective, a retrospective cohort of children born in Atlanta, Georgia, in 1981-1993 who survived to 3 years of age was identified through vital records. Children in the cohort who had developmental disabilities (autism, mental retardation, cerebral palsy, hearing loss, or vision impairment) and were still residing in metropolitan Atlanta at 3 to 10 years of age were identified through the Metropolitan Atlanta Developmental Disabilities Surveillance Program. A nested case-control sample from the cohort was used for the second objective; all cohort children identified with autism were case participants, and control participants were cohort children who were not identified as having developmental disabilities or receiving special education services. The prevalence of autism in low birth weight or preterm children was markedly lower than those of other developmental disabilities. In multivariate analyses, birth weight of <2500 g and preterm birth at <33 weeks' gestation were associated with an approximately twofold increased risk for autism, although the magnitude of risk from these factors varied according to gender (higher in girls) and autism subgroup (higher for autism accompanied by other developmental disabilities). For example, a significant fourfold increased risk was observed in low birth weight girls for autism accompanied by mental retardation, whereas there was no significantly increased risk observed in low birth weight boys for autism alone. Gender and autism subgroup differences in birth weight and gestational age, resulting in lower gender ratios with declining birth weight or gestational age across all autism subgroups, might be markers for etiologic heterogeneity in autism.

Emotional, Behavioral, Social, and Academic Outcomes in Adolescents Born With Very Low Birth Weight

Very low birth weight survivors are at increased risk of developing emotional and behavioral problems and low social and academic competencies. Information on such problems in very low birth weight adolescents is still sparse. Our purpose for this work was to study gender-specific emotional and behavioral problems and social and academic competencies in a cohort of very low birth weight adolescents in north Norway. Families with very low birth weight adolescents aged 13 to 18 years, born between 1978 and 1989 (n = 162) were addressed by mail and asked to complete the Child Behavior Check List and the Youth Self-Report. Data were compared with 2 normative adolescent populations (Child Behavior Check List, n = 540; Youth Self-Report, n = 2522). Scores given by very low birth weight adolescents and their parents on identical items in Child Behavior Check List and Youth Self-Report (cross-informant syndrome constructs) were compared in pairs. To explore predictive effects, demographic and early medical characteristics were entered into a hierarchical multiple regression analysis. There were 156 eligible families, and 99 (63.5%) responded. All completed the Child Behavior Check List, and 82 (52.6%) completed the Youth Self-Report. Very low birth weight boys reported less externalizing and internalizing behaviors and thought and attention problems and higher activity score, whereas very low birth weight girls reported less externalizing behavior and less social, thought, and attention problems and higher activity score compared with normative adolescents. Very low birth weight parents, however, reported more social and attention problems and less social and school competence in boys and more internalizing behavior and social and attention problems and less school competence in girls compared with normative parents. They scored high proportions of both genders within the borderline/clinical range on all of the scales, except for externalizing behavior and social problems in girls. Female very low birth weight adolescents, in contrast to males, reported more problems than parents when compared in pairs, and externalizing problems in particular were not recognized by parents. From parents' point of view, significant proportions of very low birth weight adolescents experience more emotional and behavioral problems and less competence than normative adolescents. In contrast, very low birth weight adolescents state less problems and similar or higher competence than normative adolescents. Very low birth weight adolescent girls report more emotional and behavioral problems compared with their parents than very low birth weight adolescent boys do. Externalizing problems in very low birth weight adolescent girls are often not recognized by parents. To better understand these seemingly paradoxical findings and to develop adequate intervention programs, there is a need for prospective longitudinal studies.

Aspects of inattention in low birth weight children

The objective of this study was to explore the nature of impaired attention in low birth weight children. A population-based sample (n = 129) of 11-year-old low birth weight children was compared with a randomized group of normal birth weight children (n = 128). Continuous Performance Test, a Cue-Target Task, and a Stroop Color-Word test were used to assess the following dimensions of attentional function: inattention, impulsivity, vigilance, selected attention, and alternating attention. The attention subscale from the Child Behavior Check List questionnaire was included to assess maternal report of inattention. Low birth weight children had generally slower reaction time than normal birth weight children and manifested impaired vigilance, but this could be attributed to group differences in confounding parental factors. Impairment was not a function of birth weight within the low birth weight group, but low birth weight boys manifested impaired vigilance compared with normal birth weight boys. Every fourth low birth weight child was reported with inattention, but small differences were found between the inattentive and attentive low birth weight children. No specific attentional dysfunction was observed in the low birth weight study group. The nature of reported impaired attention among low birth weight children is still uncertain.

Low birth weight as a vulnerability marker for early drug use.

Using prospective data from a community-based sample, the authors tested (a) whether low birth weight (LBW) was a vulnerability marker for children's early drug use and (b) whether the antecedents and sequelae of LBW may act as mediators or confounders in the pathway to early drug use. A total of 823 children and their mothers--473 LBW (<2,500 g) and 350 normal birth weight (NBW)--were assessed when the children were 6 years old and again when they were 11 years old. The incidence of drug use was higher in LBW versus NBW boys (relative odds = 2.0, 95% confidence interval = 1.2-2.6), but there was no difference in incidence for girls. The increased risk for LBW boys remained after adjustment for IQ, externalizing problems, attention-deficit/hyperactivity disorder, and maternal smoking. These findings suggest that LBW is a useful vulnerability marker for early drug use among boys, independent of the antecedents and sequelae of LBW.

Increased risk of learning disabilities in low birth weight boys at age 11 years

Background: Few studies have examined learning disabilities among low birth weight (≤2500 g) children, and those that have, have focused on very low birth weight children (<1500 g). We tested the hypothesis that low birth weight increases the risk of reading and math disabilities, examined possible sex differences in the effect of low birth weight, and assessed risk across the entire range of low birth weight. Methods: Low birth weight and normal birth weight children were randomly selected from the 1983–1985 newborn lists of an urban and a suburban hospital in southeast Michigan. Children with neurological impairments were excluded. Children were evaluated at age 6 years and at age 11 years. Of the 823 children in the initial assessment, 717 (87.1%) participated in the second assessment. The Wechsler Intelligence Scale for Children—Revised and the Woodcock-Johnson Psycho-Educational Battery—Revised were used to identify children with learning disabilities. Learning disabilities were estimated in 574 children with IQs of ≥85. Results: Low birth weight was associated with increased risk for reading and math disability in male children (odds ratio = 3.3 and odds ratio = 6.5, respectively) but not in female children. The increased risk of learning disabilities among male children applied to the entire range of low birth weight and was observed in both the urban and suburban communities. Conclusions: The effect of low birth weight on learning disabilities appears to be specific to male children. Although this sex-specific effect is consistent with previous findings of a greater vulnerability of male children to pregnancy and birth complications, it remains to be replicated and clarified.

Very Low Birthweight Boys at the Age of 19

Centre for Epidemiology, National Board of Health, Stockholm, and Tornblad Institute, University of Lund, Lund, Sweden Arch Dis Child Fetal Neonatal Ed 1998;78:F171-F174

Very low birthweight boys at the age of 19

Using linked data from the Swedish Medical Birth Registry and the National Service Enrolment Register, long term follow up (to 18–19 years age) was made of 260 surviving singleton boys...

Low birthweight and neuromotor development: a population based, controlled study.

The aims of the study were to investigate: (a) the relationship between low birthweight (LBW) and pre-school neuromotor development; and (b) the predictive value of various pre-, peri-, and neonatal factors for neuromotor development in LBW pre-school children. A population based sample of 144 5-year-old LBW children (birthweight < 2000 g) with no major handicaps was compared with a random sample of 163 normal birthweight term controls. Using the Peabody Developmental Motor Scales, impaired performance on the balance scale was seen more often in LBW boys than in controls (odds ratio 5.5, 95% CI 1.5-20.3), while performance on the eye-hand coordination and locomotor scales was comparable for the two groups. LBW girls were comparable to controls on all these scales. On neurological examination, an increased frequency of minor neurological signs was found in LBW boys, while increased ankle tone and/or leg hyperreflexia was more common in LBW girls compared to controls. Small head circumference at birth was associated with an increased frequency of minor neurological signs in LBW boys, and lack of breastmilk in the neonatal period with impaired balance in LBW boys. None of the other pre-, peri- or neonatal factors were predictive of neuromotor development. We conclude that motor functions essential for daily activities are intact in most LBW preschoolers.

Five-year-follow-up of very low birthweight infants: neurological and psychological outcome.

All surviving infants with birthweight < or = 1500 g born in 1982 and 1983 at St. James's University Hospital, Leeds, were followed up for 5 years. There were 88 survivors (including 5 in utero transfers) from the original cohort of 126 infants. In their fifth year the following assessments were made: neurological, audiological, intellectual, behavioural, growth and general health. A comparison group of full-term male infants was also studied with respect to intellectual status, social and emotional behaviour and general health. Principal neurological impairments found were: cerebral palsy 9 (10.2%), hydrocephalus 1 (1.1%), epilepsy 2 (2.3%) and sensorineural deafness 2 (2.3%). One third of the VLBW children required the services of the child development centre. Seventy-nine of the 88 VLBW children were tested with the WPPSI. Seven (8.8%) scored below 70. The VLBW boys had mean IQ scores of 90.6 while the mean for the girls was 100.2. The very low birthweight boys were significantly intellectually impaired compared with their peers. Socially and emotionally they were largely comparable with their full-term peers. The findings suggest that there has been no increase in severe disability following a policy of active neonatal intensive care. However, the quality of survival of VLBW children born in the 1980s, despite improvements in perinatal care, remains a major concern.

Prognosis of the very low birthweight baby in relation to gender.

The effects of gender on mortality and morbidity of all neonates weighing less than 1500 g admitted to King's College Hospital Neonatal Intensive Care Unit during 1980-82 (n = 271) were examined. Very low birthweight boys had a significantly higher mortality and more postnatal complications than girls. The higher incidence of respiratory distress syndrome and pulmonary interstitial emphysema in boys was associated with increased mortality in the first year. Surviving boys had significantly more problems, including lower Apgar scores at five minutes, more frequent apnoeic attacks and bradycardic episodes, transient tachypnoea, neonatal anaemia, and lower blood calcium and phosphate concentrations. Surviving children were followed up at 1 and 2 years of age. Development of boys at 1 year was significantly delayed compared with girls in all fields save locomotor. Although at 2 years some of the differences had diminished, those in language and personal social skills were more pronounced. More than twice as many boys as girls had major neurodevelopmental disorders.