Maternal health in pregnancy and intellectual disability in the offspring: a population-based study

PURPOSE: The aim of the study is to investigate the relationship between common maternal conditions and intellectual disability (ID) of unknown cause in the offspring. METHODS: Information about the maternal health of children with and without ID was obtained by using record linkage. For mothers with specific medical conditions, proportions of children with mild to moderate ID, severe ID, and autism spectrum disorder (ASD) with ID were compared with those who did not have ID. RESULTS: There was an increased risk for mild to moderate ID in children of mothers with asthma (odds ratio [OR], 1.52; confidence interval [CI], 1.26-1.83]), diabetes (OR, 1.69; CI, 1.26-2.27), a renal or urinary condition (OR, 2.09; CI, 1.39-3.14), and epilepsy (OR, 3.53; CI, 2.56-4.84). ASD risk was increased for children of women with diabetes (OR, 2.89; CI, 1.28-6.51) and epilepsy (OR, 4.57; CI, 1.69-12.31). For anemia (n = 1101), there was an increased risk for severe ID (OR, 5.26; CI, 2.16-12.80). CONCLUSIONS: The increased risk for ID in offspring of mothers with such conditions as asthma and diabetes is particularly important for disadvantaged or ethnic populations, for whom these conditions are more prevalent and may be less well managed.     

Co-occurrence of birth defects and intellectual disability

This study used population-based databases to ascertain birth defects and intellectual disability (ID), defined as full IQ < 70, in children born in Western Australia during 1980-99. Of the children surviving to 1 year (n = 474 285), 4.9% had birth defects and 1.3% ID. ID was identified in 7.9% of children with birth defects. After adjusting for sex, mother's age, race, parity, plurality, birthweight and gestational age the prevalence ratio (PR) [95% confidence interval (CI)] for ID in children with birth defects compared with those with no birth defects was 7.6 [7.2, 8.0]. Those with chromosomal anomalies comprised 3.2% of the group with birth defects. The percentage ID (and PR [95% CI]) in specific categories were: Down's syndrome 97% (84.5 [79.4, 90.0]), sex chromosome anomalies 30.3% (31.0 [23.8, 40.3]), other chromosomal anomalies 64.2% (54.2 [47.2, 62.3]). Birth defects were categorised according to system in the 96.8% of children with non-chromosomal anomalies. The percentage with ID (and PR [95% CI]) for birth defects in each system were: spina bifida 18.8 (16.7 [12.2, 23.0]); nervous (except spina bifida) 38.6 (33.4 [30.3, 36.9]); cardiovascular 4.2 (4.1 [3.5, 4.8]); gastro-intestinal 2.2 (2.0 [1.5, 2.7]); urogenital 2.6 (2.4 [2.0, 2.8]; musculo-skeletal 3.6 (4.0 [3.5, 4.6]); other non-chromosomal 7.0 (7.3 [6.5, 8.3]); and multiple systems 12.3 (10.2 [8.6, 12.2]). Birth defects were present in 30.2% of children with ID (27.7% of children with mild/moderate ID (IQ 40-69) and 54% of children with severe ID (IQ < 40)). Adjusted PRs for birth defects in children with any ID, mild/moderate ID and severe ID compared with children with normal intellectual function were 6.0 [5.8, 6.3], 5.5 [5.3, 5.8] and 10.5 [9.7, 11.4] respectively. The data are useful for those providing services for children with developmental disabilities especially for predicting family support and respite and accommodation requirements for children and adults with severe ID.     

Relation between intrauterine growth and subsequent intellectual disability in a ten-year population cohort of children in Western Australia

The authors investigated the association between intrauterine growth and intellectual disability (ID). The appropriateness of intrauterine growth was assessed using percentage of optimal birth weight, a measure that accounts for gestational age, maternal height, parity, and infant sex. Using population-based record linkage, singleton Caucasian and Aboriginal children born in Western Australia in 1983-1992 and alive in 2002 with ID of unknown cause (n = 2,625) were compared with children without ID (n = 217,252). The odds of ID increased with less-than-optimal intrauterine growth. In Caucasian children, after adjustment for sociodemographic factors, severe growth restriction was associated with development of mild-moderate ID among preterm births (<37 weeks) (odds ratio (OR) = 1.71, 95% confidence interval (CI): 1.06, 2.77) and term births (> or =37 weeks) (OR = 2.42, 95% CI: 1.88, 3.12) and with severe ID (OR = 4.79, 95% CI: 2.59, 8.83) among term births. Effects were similar among Aboriginal children. Severe growth restriction (OR = 3.2, 95% CI: 1.3, 7.9) and poor head growth (OR = 3.6, 95% CI: 1.4, 9.0) were independently associated with severe ID. Infants with excess intrauterine growth were more likely to be diagnosed with ID associated with autism spectrum disorder (OR = 2.36, 95% CI: 0.93, 6.03). These findings suggest that inappropriate intrauterine growth, less than or greater than optimal birth weight, is associated with development of ID.     

Disparities in the prevalence of cognitive delay: how early do they appear?

Cognitively delayed children are at risk for poor mental and physical health throughout their lives. The economically disadvantaged and some race/ethnic groups are more likely to experience cognitive delay, but the age at which delays first emerge and the underlying mechanisms responsible for disparities are not well understood. The objective of this study was to determine when sociodemographic disparities in cognitive functioning emerge, and identify predictors of low cognitive functioning in early childhood. Data were from 7308 singleton and 1463 multiple births in the Early Childhood Longitudinal Study‐Birth Cohort (ECLS‐B), a nationally representative cohort of children born in the USA in 2001. Multiple logistic regression analyses examined associations between sociodemographic characteristics and low cognitive functioning at 9 and 24 months, and tested whether gestational and birth‐related factors mediate these associations. Sociodemographic characteristics were statistically significant predictors of low cognitive functioning among singletons at 24 months, including the three lowest quintiles of socio‐economic status [lowest quintile, odds ratio (OR) = 2.7, 95% confidence interval [CI][1.7, 4.1]], non‐white race/ethnicity (African American OR = 1.8 [95% CI 1.3, 2.5], Hispanic OR = 2.3 [95% CI 1.6, 3.2]), and gender (male OR = 2.1, [95% CI 1.7, 2.5]). Gestational and birth characteristics associated with low cognitive function at 9 months included very low and moderately low birthweight (OR = 55.0 [95% CI 28.3, 107.9] and OR = 3.6 [95% CI 2.6, 5.1]), respectively, and very preterm and moderately preterm delivery (OR = 3.6 [95% CI 2.0, 6.7] and OR = 2.4 [95% CI 1.7, 3.5]), respectively, but they had weaker effects by 24 months (ORs for birthweight: 3.7 [95% CI 2.3, 5.9] and 1.8 [95% CI 1.4, 2.3]; ORs for preterm: 1.8 [95% CI 1.1, 2.9] and 0.9 [95% CI 0.7, 1.3]). Results for multiple births were similar. Sociodemographic disparities in poor cognitive functioning emerged by 24 months of age, but were not mediated by gestational or birth characteristics. Further investigation of processes whereby social disadvantage adversely affects development prior to 24 months is needed.     

Maternal diet and the risk of hypospadias and cryptorchidism in the offspring

Male genital tract birth defects have been associated in previous studies with several prenatal exposures to environmental and dietary risk factors. The purpose of this study was to explore the association between hypospadias and cryptorchidism, and the dietary habits of an agricultural population in Italy. A population-based case-control study was conducted in the Sicilian Province of Ragusa. Cases (n = 90) and controls (n = 202) included births for the period 1998-2002. Data on dietary habits of the mothers, as well as health-related social, occupational and environmental exposures prior to and during the index birth, were collected through interviews. Adjusted odds ratios (OR) were calculated by logistic regression after adjustment for confounding variables. Increased ORs were observed for mothers of children with hypospadias who, during pregnancy, frequently consumed fish (OR = 2.33 [95% confidence interval (CI) 1.03, 5.31]) and market-purchased fruit (OR = 5.10 [95% CI 1.31, 19.82]). For cryptorchidism, increased risk was observed in mothers consuming liver (OR = 5.21 [95% CI 1.26, 21.50]), and smoked products (OR = 2.46 [95% CI 1.15, 5.29]). For the two malformations pooled together, increased risk was associated with maternal consumption of liver (OR = 4.38 [95% CI 1.34, 14.26]) and with frequent consumption of wine (OR = 1.98 [95% CI 1.01, 3.86]). This study suggests that some maternal dietary factors may play a role in the development of congenital defects of the male reproductive tract. In particular, our data indicate that further research may be warranted on the endocrine-disrupting effects resulting from the bioaccumulation of contaminants (fish, liver), pesticides (marketed fruit, wine) and/or potentially toxic food components (smoked products, wine, liver).     

Active and passive smoking during pregnancy and risk of central nervous system tumours in children

The effects of maternal active and passive smoking during pregnancy on childhood central nervous system (CNS) tumours were assessed in a population-based case-control study. The mothers of 244 children aged 0-15 years with CNS tumours and 502 control mothers were interviewed about their smoking habits. All families were resident in the region of Lombardy, Italy. Risk estimates were calculated by unconditional logistic regression, adjusted for age, sex and area of residence. Active smoking by the parents before pregnancy was not associated with increased risk of CNS tumours in the children. Active smoking by the mother during early pregnancy (approximately the first 5 weeks) was associated with a slightly increased risk of the child developing a CNS tumour (odds ratio [OR] 1.5 [95% CI 1.0, 2.3]). An increased risk of CNS tumours was found in the children of non-smoking mothers exposed regularly to tobacco smoke both in early pregnancy (OR 1.8 [95% CI 1.2, 2.6]) and in late pregnancy (OR 1.7 [95% CI 1.2, 2.5]). Although this study was retrospective, the results confirm our previous findings and suggest an association between the risk of developing CNS tumours in children and regular passive smoking by the mother during pregnancy.     

Moderate neonatal hypoglycemia and adverse neurological development at 2–6 years of age

To determine whether moderate neonatal hypoglycemia in otherwise healthy infants is associated with adverse neurodevelopmental outcome in pre-school children. Population-based cohort study with prospectively collected register data from Sweden. All singletons born July 1st 2008 through December 31st 2012 (n?=?101,060) in the region were included. Infants with congenital malformations, infants treated in neonatal intensive care unit, infants with inborn errors of metabolism and infants to mothers with diabetes were excluded. Infants were followed-up until 2014, at 2–6 years of age. Exposure was neonatal moderate hypoglycemia. Main outcomes were a compiled neurological or neurodevelopmental outcome; any developmental delay; motor developmental delay; and cognitive developmental delay. In adjusted regression analyses, the odds ratio (OR) of any neurological or neurodevelopmental outcome was 1.48 (95% confidence interval: 1.17–1.88) in hypoglycemic compared to normoglycemic infants. The adjusted risk of any developmental delay was more than doubled (OR 2.53 [1.71–3.73]), the adjusted risk of motor developmental delay was almost doubled (OR: 1.91 [1.06–3.44]) and the adjusted risk of cognitive developmental delay was almost tripled (OR 2.85 [1.70–4.76]). Infants with early neonatal hypoglycemia (<?6 h) had a double risk (OR 1.94 [1.30–2.89]) of any neurological or neurodevelopmental outcome and a tripled risk of cognitive developmental delay (OR 3.17 [1.35–7.43]), compared to normoglycemic infants. In the first population-based study on this topic, we show that moderate neonatal hypoglycemia is associated with increased risks of impaired neurodevelopment. Current treatment routines for uncomplicated hypoglycemia should be followed.     

Maternal Dietary Intake of Folate and Vitamins B6 and B12 During Pregnancy and Risk of Childhood Brain Tumors

Childhood brain tumors (CBT) are the second most common childhood cancers, yet their etiology is largely unknown. We investigated whether maternal gestational intake of folate and vitamins B6 and B12 was associated with CBT risk in a nationwide case-control study conducted 2005–2010. Case children 0–14 years were recruited from all 10 Australian pediatric oncology centers. Control children were recruited by national random digit dialing, frequency matched to cases on age, sex, and state of residence. Dietary intake was ascertained using food frequency questionnaires and adjusted for total energy intake. Data from 293 case and 726 control mothers were analyzed using unconditional logistic regression. The odds ratio (OR) for the highest versus lowest tertile of folate intake was 0.70 [95% confidence interval (CI): 0.48, 1.02]. The ORs appeared lower in mothers who drank alcohol during pregnancy (OR = 0.45, 95% CI: 0.22, 0.93), mothers who took folic acid (OR = 0.67, 95% CI: 0.42, 1.06) or B6/B12 supplements (OR = 0.51, 95% CI: 0.25, 1.06) and in children younger than 5 years (OR = 0.50, 95% CI: 0.27, 0.93). These findings are consistent with folate's crucial role in maintenance of genomic integrity and DNA methylation. Dietary intake of B6 and B12 was not associated with risk of CBT.     

Predominant breast-feeding from birth to six months is associated with fewer gastrointestinal infections and increased risk for iron deficiency among infants

Iron deficiency (ID) is prevalent among infants world-wide and may be more likely among infants born to women living in disadvantaged environments. A strategy to address ID in this context is to feed iron-fortified formula, but this may create risk for gastrointestinal (GI) infection. Our objective was to investigate the relationship between infant feeding practices, iron status, and likelihood of a GI infection in the first 6 mo of life. We conducted a prospective study at a public hospital in Guadalajara, Mexico. Healthy women who gave birth to a healthy term infant were eligible to participate. Each month, mothers (n = 154) provided information on infant feeding methods and symptoms of GI infection. At 6 mo of age, infants' iron status was assessed [hemoglobin (Hb) and serum ferritin concentration]. When compared with nonpredominantly breast-fed [partially breast-feeding (PBF) and formula feeding (FF) combined], predominantly breast-fed (PRBF) infants to 6 mo had a lower incidence of GI infection from 0-6 mo [18 vs. 33%; P = 0.04; adjusted odds ratio (OR) = 0.4; 95% CI = 0.2, 1.0] but a higher risk for ID (serum ferritin < 12 microg/L) at 6 mo (22 vs. 4%; P = 0.001; adjusted OR = 9.2; 95% CI = 2.3, 37.0). Anemia (Hb < 110 g/L) prevalence did not differ among feeding groups (13% for PRBF, 19% for PBF, and 4% for FF; P = 0.09). In this low-income population, our results suggest that PRBF should be promoted and the risk for ID managed using public health and nutrition strategies.     

Wilms' tumour: a systematic review of risk factors and meta‐analysis

Chu A, Heck JE, Ribeiro KB, Brennan P, Boffetta P, Buffler P, Hung RJ. Wilms' tumour: a systematic review of risk factors and meta‐analysis. Paediatric and Perinatal Epidemiology 2010. Wilms' tumour comprises 95% of all renal cancers among children less than 15 years of age. The purpose of this review is to examine the existing literature on perinatal and environmental risk factors for Wilms' tumour. A search for epidemiological studies that examined risk factors for Wilms' tumour was undertaken in Medline, LILACS, ISI Web of Science and Dissertation Abstracts. A total of 37 studies, including 14 cohort, 21 case–control and 2 case–cohort studies, were identified that examined environmental and perinatal risk factors. Most studies were from Western Europe and North America, and among case–control studies, 16 used randomly selected population‐based controls. We observed a significantly increased risk of Wilms' tumour with maternal exposure to pesticides prior to the child's birth (OR = 1.37 [95% CI 1.09, 1.73]), high birthweight (OR = 1.36 [95% CI 1.12, 1.64]) and preterm birth (OR = 1.44 [95% CI 1.14, 1.81]), although the results regarding pesticide exposure may be subject to publication bias (Egger's test, P = 0.09). Further analyses to adjust for the heterogeneity in the results for high birthweight and preterm birth did not statistically change the significance of the results. Additionally, an increased though not statistically significant risk of Wilms' tumour was associated with maternal hypertension (OR = 1.30 [95% CI 0.99, 1.72]), and, compared with the first born, being a second or later birth was associated with a significantly decreased risk (OR = 0.82 [95% CI 0.71, 0.95]). This review suggests a role for several perinatal and environmental risk factors in the aetiology of Wilms' tumour.     

Determinants of Small for Gestational Age Birth at Term

Background: Being born small for gestational age (SGA) is an indicator of intrauterine growth restriction (IUGR) and later health risks. This study investigated determinants of severe and moderate SGA (respectively, birthweight <3rd percentile and 3rd to <10th percentile for gestational age and sex). Methods: A total of 2195 term pregnancies from a prospective cohort were studied. Prenatal data arose from maternal interview at 10–22 weeks of gestation and perinatal data were collected from hospital charts. Severe and moderate SGA were classified by Canadian population standards. Risk factors for SGA were identified from fitting multivariable logistic regression models. Results: Multivariable associations with severe SGA were: maternal age ≥ 35 [odds ratio (OR) 3.2 [95% confidence interval (CI) 1.4, 6.9]], maternal smoking during pregnancy (OR 5.3 [95% CI 2.4, 11.7]), preeclampsia (OR 4.6 [95% CI 1.6, 13.2]) and threatened preterm labour (OR 3.9 [95% CI 1.3, 11.4]). Primiparity was associated with both severe and moderate SGA with OR 2.4 [95% CI 1.1, 5.1] and OR 1.9 [95% CI 1.3, 2.9] respectively. Underweight pre‐pregnancy body mass index was associated with moderate SGA (OR 2.4 [95% CI 1.2, 5.0]). Inclusion of placental weight, in the final model attenuated the associations. Conclusions: This study demonstrated different determinants for severe and moderate SGA. We speculate that the majority of severe SGA infants are IUGR while moderate SGA infants may be a mixture of IUGR and constitutionally small newborns. This study has also contributed evidence linking preterm labour and SGA as two, potentially related, outcomes of overlapping causal mechanisms reflective of ischaemic placental disease.     

Inadequate prenatal care and elevated blood lead levels among children born in Providence, Rhode Island: a population-based study

OBJECTIVE: This study was conducted to determine whether children born to mothers receiving inadequate prenatal care are at an increased risk for having an elevated blood lead level during early childhood. METHODS: The authors conducted a population-based study of children born in Providence, Rhode Island, from 1997 to 2001 whose mothers had received adequate, intermediate, or inadequate prenatal care. The children's blood lead levels were compared between groups using bivariate and logistic regression. To understand the regulatory implications and public health impact of changing the definition of an elevated blood lead level, "elevated" was defined as 5 microg/dL, 10 microg/dL, and 15 microg/dL. RESULTS: Children born to mothers who received inadequate prenatal care were at an elevated risk for having an elevated blood lead level later in life. This relationship remained statistically significant for each definition of elevated blood lead level and after controlling for other socio-economic status measures and birthweight (at 5 microg/dL, odds ratio [OR] = 1.36, 95% confidence interval [CI] 1.09, 1.68, p = 0.006; at 10 microg/dL, OR = 1.68, 95% CI 1.26, 2.24, p < 0.0004; at 15 microg/dL, OR = 1.83, 95% CI 1.10, 3.04, p = 0.019) represent an opportune moment to identify expectant mothers living in lead-contaminated environments. CONCLUSIONS: Results suggest that conducting lead screening as a regular part of prenatal care provision could help identify women possibly experiencing ongoing lead exposure and help reduce or prevent exposures to their offspring.     

Determinants of developmental delay in infants aged 12 months

The aim of this study was to determine which demographic, maternal, obstetric and postnatal variables were associated with achievement of developmental milestones at the age of 12 months in term infants. Mothers and babies were enrolled in the Auckland Birthweight Collaborative Study shortly after birth. All infants were full term (gestation >or= 37 weeks). Approximately half of the sample were small for gestational age (SGA = birthweight 10th percentile). A maternal interview was conducted soon after birth. Phase 2 of the study occurred 12 months later when mothers were sent a postal questionnaire requesting information about the child's health and development during the first year of life using the Denver Prescreening Developmental Questionnaire. Seven hundred and forty-four (85.4%) European mothers returned the postal questionnaire. SGA children were not at increased risk of developmental delay at 12 months of age. In a sample representative of New Zealand European children, after adjustment for the effects of potential confounders, maternal smoking during pregnancy (OR = 2.1 [95% CI 1.1, 4.0]), maternal smoking during the first year of life (OR = 1.9 [95% CI 1.0, 3.8]) and low levels of satisfaction with parenting (OR = 2.4 [95% CI 1.1, 5.2]) were associated with significantly increased risk of developmental delay. In the subgroup of SGA children, maternal smoking during pregnancy (OR = 2.9 [95% CI 1.4, 6.2]), high levels of stress associated with parenting (OR = 2.2 [95% CI 1.2, 4.0]), and low levels of satisfaction with parenting (OR = 4.3 [95% CI 1.3, 13.5]) were significantly associated with developmental delay after adjustment for the effects of potential confounders. In conclusion, maternal and postnatal factors were better predictors of developmental delay than demographic variables.     

Maternal and gestational risk factors for hypospadias

BACKGROUND: An increase in the prevalence of hypospadias has been reported, but the environmental causes remain virtually unknown. OBJECTIVES: Our goal was to assess the association between risk of hypospadias and indicators of placental function and endogenous hormone levels, exposure to exogenous hormones, maternal diet during pregnancy, and other environmental factors. METHODS: We conducted a case-control study in Sweden and Denmark from 2000 through 2005 using self-administered questionnaires completed by mothers of hypospadias cases and matched controls. The response rate was 88% and 81% among mothers of cases and controls, respectively. The analyses included 292 cases and 427 controls. RESULTS: A diet during pregnancy lacking both fish and meat was associated with a more than 4-fold increased risk of hypospadias [odds ratio (OR) = 4.6; 95% confidence interval (CI), 1.6-13.3]. Boys born to obese [body mass index (BMI) > or = 30] women had a more than 2-fold increased risk of hypospadias (OR = 2.6; 95% CI, 1.2-5.7) compared with boys born to mothers with a normal weight (BMI = 20-24). Maternal hypertension during pregnancy and absence of maternal nausea increased a boy's risk of hypospadias 2.0-fold (95% CI, 1.1-3.7) and 1.8-fold (95% CI, 1.2-2.8), respectively. Nausea in late pregnancy also appeared to be positively associated with hypospadias risk (OR = 7.6; 95% CI, 1.1-53). CONCLUSIONS: A pregnancy diet lacking meat and fish appears to increase the risk of hypospadias in the offspring. Other risk associations were compatible with a role for placental insufficiency in the etiology of hypospadias.     

Socioeconomic factors and risk of hospitalization with infectious diseases in 0- to 2-year-old Danish children

Although the association between low socioeconomic status and illness in childhood is well known, the impact of socioeconomic factors on risk and frequency of hospitalizations for infectious diseases, the most frequent disease category, during the first 2 years of life has scarcely been studied. Through linkage of records drawn from public administrative and health registries, we conducted a population-based cohort study of 5024 Danish children born in 1997 to examine the frequency of hospitalization for infectious diseases in very young children. The main exposure variables, adjusted for potential confounding factors, were mother’s education level, household income, and cohabitation status. The outcome was number of hospital admissions (0, 1–2, or 3+) for infectious diseases. A total of 737 children (14.7%) were admitted to hospital 1–2 times, and 83 (1.6%) were admitted 3–10 times. The risk of hospitalization was increased in children of mothers with a low level of education compared with vocational education (1–2 admissions: adjusted odds ratio (OR) 1.3 (95% confidence interval [CI]: 1.1–1.6). Children from low-income families had an increased risk of 3 or more admissions (low cf middle income: adjusted OR 2.0 [95% CI: 0.6–6.0]). Children of single mothers had an increased risk of hospitalization (1–2 admissions: adjusted OR 1.7 [95% CI: 1.1–2.6]. We found the highest risk of hospitalization for infectious diseases in children of mothers with only basic schooling, and particularly among those coming from single parent homes with a low income.     

Caesarean route of delivery and hyaline membrane disease: a hospital-based case-control study in Greater Beirut

A hospital-based case-control study was conducted to examine the relationship between hyaline membrane disease (HMD) and caesarean route of delivery, in light of sociodemographic, obstetric and perinatal confounders and risk modifying factors. The study population consisted of 78 HMD cases and a control group of 803 infants delivered at 25-36 weeks' gestation and admitted over a 16-month period to nine hospitals in Greater Beirut, Lebanon. The likelihood of delivery by caesarean section was nearly twice as high among newborn infants diagnosed with HMD as compared with the non-HMD control group (OR = 2.02, [95% CI 1.04, 3.92], after adjusting for fetal growth ratio, one-minute Apgar score, maternal age, antenatal steroid administration and pregnancy-related complications. The impact of caesarean section on HMD was considerably more important in infants delivered < or = 32 weeks' gestation (OR = 2.10, [95% CI 0.79, 5.52]) as compared with those delivered afterwards (OR = 1.13, [95% CI 0.40, 3.21]).     

One- and two-year predictors of decline in physical activity among inner-city schoolchildren

BACKGROUND: Alarming secular declines in physical activity (PA) have been observed among youth over the last decade. A better understanding of the predictors of these declines is crucial to identifying those children most at risk and to developing interventions that target youth before the onset of decline. This report identifies 1- and 2-year predictors of decline in PA among fourth- and fifth-grade students from inner-city neighborhoods in Montreal, Canada. METHODS: Data for this study were collected in classroom questionnaires each May/June from 1993 to 1997. Analyses for this paper were completed in 2001. The cohort included active (at least one PA per day) children with baseline and 1-year (n =1873) or 2-year (n =509) follow-up data. RESULTS: In boys, 1-year predictors of decline to an inactive status identified in generalized estimating equations analysis included moderate (vs high) baseline PA (odds ratio [OR]=1.66, 95% confidence interval [CI]=0.91-3.05); low PA self-efficacy (OR=1.67, 95% CI=1.03-2.71); born outside Canada (OR=2.13; 95% CI=1.31-3.46); Asian origin (OR=1.81; 95% CI=1.03-3.16) and no participation in school teams (OR=1.81, 95% CI=0.93-3.55). In girls, these 1-year predictors included moderate PA (OR=1.91, 95% CI=1.10-3.32); low PA self-efficacy (OR=1.70, 95% CI=1.15-2.49); watching four or more TV programs per day (OR=1.40, 95% CI=0.97-2.02); mother unemployed (OR=1.54, 95% CI=1.07-2.23); and grade five (vs grade four) (OR=1.35, 95% CI=0.94-1.93). Two-year predictors in boys included moderate baseline PA (OR=2.52, 95% CI=0.84-7.50), and born outside Canada (OR=1.96, 95% CI=0.91-4.20). In girls, these 2-year predictors included moderate baseline PA (OR=2.75, 95% CI=1.01-7.49); no participation in school teams (OR=2.14, 95% CI=0.92-5.00); watching four or more TV programs per day (OR=1.93, 95% CI=0.99-3.74); and born outside Canada (OR=1.85, 95% CI=0.96-3.55). CONCLUSIONS: Reduced TV viewing among girls and increased participation in school sports teams in boys and girls may prevent declines in PA among pre-adolescents from inner-city neighborhoods.     

Breastfeeding practices and associated factors among children under 24 months of age in Timor-Leste

OBJECTIVE: To describe breastfeeding practices and to assess the sociodemographic factors associated with selected breastfeeding indicators. DESIGN AND SETTING: The 2003 Demographic and Health Survey was a multi-stage cluster sample survey of 4320 households from four different geographic areas in Timor-Leste. SUBJECTS: A total of 2162 children aged 0-23 months. RESULTS: A high proportion (97.6%) of infants had been ever breastfed, but only 46.1% had initiated breastfeeding within the first hour of birth. Seventy-eight percent of children <24 months were currently breastfed, 30.7% of infants <6 months were exclusively breastfed and 12.5% of infants <12 months were bottle-fed. A high proportion of infants of 6-9 months (82.0%) were receiving complementary food in addition to breast milk. Multivariate analysis revealed that exclusive breastfeeding was significantly lower in the rural west region (odds ratio (OR)=3.15) compared to the urban region, and among those from richest households (OR=1.90) compared to poorest. Mothers with primary education were significantly more likely to exclusively breastfeed than mothers with no education (OR=0.62). Increasing age of the infant was associated with significantly less current (OR=1.23) and exclusive (OR=1.35) breastfeeding. Continuation of breastfeeding at the end of the first year was significantly lower in non-working mothers (OR=1.58) compared to working mothers, and among infants born in health-care facilities (OR=2.16) than those born at home. CONCLUSIONS: Breastfeeding practices in Timor-Leste were satisfactory, except the exclusive breastfeeding at 6 months. However, more socioeconomically privileged groups demonstrated a poorer breastfeeding performance than disadvantaged groups. Further breastfeeding promotion programmes are needed across all population groups, and should include health-care providers and maternity institutions.     

Association of birth outcomes and maternal, school, and neighborhood characteristics with subsequent numeracy achievement

This study investigated the relation between birth characteristics and numeracy attainment at age 8 years. Using a multilevel approach, the authors analyzed all non-Aboriginal singletons born in Western Australia who attended government schools and participated in a Western Australia-wide numeracy test in grade 3 between 1999 and 2005. Appropriateness of intrauterine growth was expressed as the proportion of optimal growth parameters for gestational duration, infant sex, and maternal height and parity, which was derived from a total population of births without risk factors for growth restriction. After the authors controlled for sociodemographic factors, term birth and proportion of optimal head circumference at birth were associated with higher numeracy scores. Increasing proportion of optimal birth length and being firstborn were associated with relatively higher numeracy scores among children born to mothers residing in the most educationally deprived area. The relative advantage of being born first was also higher for children born to single mothers. In contrast, higher Apgar scores and greater proportion of optimal birth weight were associated with a lower relative advantage for children born to single mothers. In summary, term birth and increased growth in head circumference and length are key birth characteristics associated with higher numeracy scores, especially among disadvantaged children.