Objective: To examine the relationship between maternal intelligence-mental health and neuropsychological development at age 14 months in a normal population, taking into account maternal occupational social class and education. Methods: We prospectively studied a population-based birth cohort, which forms part of the INMA (Environment and Childhood) Project. Cognitive and psychomotor development was assessed at 14 months using Bayley Scales of Infant Development. Maternal intelligence and mental health were assessed by the Cattell and Cattell test and the General Health Questionnaire-12 respectively. Results: We observed a crude association between maternal intelligence and cognitive development in children at 14 months but this association disappeared when maternal education was included. The associations were stratified by maternal education and occupational social class. Within the manual maternal occupational social class, there was a significant difference in cognitive development between children whose mothers scored in the highest tertile of maternal IQ and those whose mothers scored in the lowest tertile. In contrast, no differences were observed among children whose mothers were in the non-manual occupational social class. Conclusions: The association between maternal intelligence and child cognitive development differed by occupational social class. While this association was not confounded by education or other variables in manual occupational social classes, maternal education explained this association among advantaged occupational social classes.

Objetivos: Este estudio exploró la relación entre inteligencia y salud mental materna y desarrollo neuropsicológico infantil a los 14 meses de edad en población normal, teniendo en cuenta la clase social basada en la ocupación y el nivel educativo maternos. Métodos: Estudio prospectivo de cohortes de nacimiento englobado dentro del proyecto INMA (Infancia y Medio Ambiente). El desarrollo cognitivo y psicomotor fue evaluado mediante la escala Bayley de desarrollo infantil. La inteligencia y la salud mental maternas se evaluaron usando el Test de Cattell y Cattell, y el Cuestionario de Salud General de 12 ítems, respectivamente. Resultados: Se observó una asociación cruda entre inteligencia materna y desarrollo cognitivo infantil a los 14 meses de edad. Sin embargo, esta asociación desaparecía cuando la educación materna era incluida. Las asociaciones fueron estratificadas por educación y clase social basada en la ocupación materna. En el estrato de clase social manual materna se observó una diferencia significativa en la escala mental de la escala Bayley entre esos niños cuyas madres puntuaron en el tercil más alto de inteligencia materna, comparado con el tercil más bajo. No obstante, no se observaron diferencias entre aquellos niños de clase social no manual materna. Conclusiones: Existe un patrón diferente en la asociación entre inteligencia materna y desarrollo cognitivo infantil según la clase social materna. Mientras la asociación no es confundida por la educación ni por otras variables en las clases sociales manuales, el nivel educativo materno explica esta asociación en las clases sociales no manuales.

Objective: To examine the relationship between maternal intelligence-mental health and neuropsychological development at age 14 months in a normal population, taking into account maternal occupational social class and education. Methods: We prospectively studied a population-based birth cohort, which forms part of the INMA (Environment and Childhood) Project. Cognitive and psychomotor development was assessed at 14 months using Bayley Scales of Infant Development. Maternal intelligence and mental health were assessed by the Cattell and Cattell test and the General Health Questionnaire-12 respectively. Results: We observed a crude association between maternal intelligence and cognitive development in children at 14 months but this association disappeared when maternal education was included. The associations were stratified by maternal education and occupational social class. Within the manual maternal occupational social class, there was a significant difference in cognitive development between children whose mothers scored in the highest tertile of maternal IQ and those whose mothers scored in the lowest tertile. In contrast, no differences were observed among children whose mothers were in the non-manual occupational social class. Conclusions: The association between maternal intelligence and child cognitive development differed by occupational social class. While this association was not confounded by education or other variables in manual occupational social classes, maternal education explained this association among advantaged occupational social classes.

Objetivos: Este estudio exploró la relación entre inteligencia y salud mental materna y desarrollo neuropsicológico infantil a los 14 meses de edad en población normal, teniendo en cuenta la clase social basada en la ocupación y el nivel educativo maternos. Métodos: Estudio prospectivo de cohortes de nacimiento englobado dentro del proyecto INMA (Infancia y Medio Ambiente). El desarrollo cognitivo y psicomotor fue evaluado mediante la escala Bayley de desarrollo infantil. La inteligencia y la salud mental maternas se evaluaron usando el Test de Cattell y Cattell, y el Cuestionario de Salud General de 12 ítems, respectivamente. Resultados: Se observó una asociación cruda entre inteligencia materna y desarrollo cognitivo infantil a los 14 meses de edad. Sin embargo, esta asociación desaparecía cuando la educación materna era incluida. Las asociaciones fueron estratificadas por educación y clase social basada en la ocupación materna. En el estrato de clase social manual materna se observó una diferencia significativa en la escala mental de la escala Bayley entre esos niños cuyas madres puntuaron en el tercil más alto de inteligencia materna, comparado con el tercil más bajo. No obstante, no se observaron diferencias entre aquellos niños de clase social no manual materna. Conclusiones: Existe un patrón diferente en la asociación entre inteligencia materna y desarrollo cognitivo infantil según la clase social materna. Mientras la asociación no es confundida por la educación ni por otras variables en las clases sociales manuales, el nivel educativo materno explica esta asociación en las clases sociales no manuales.

O objetivo deste estudo é revisar evidências epidemiológicas da associação entre a exposição a subprodutos da desinfecção com cloro (DBPs) e anomalias congênitas. Todos os estudos epidemiológicos que avaliaram a relação entre o índice de exposição a DBPs e o risco de anomalias congênitas foram analisados. Para todas as anomalias congênitas combinadas, a meta-análise resultou em um risco de excesso estatisticamente significante para alta versus baixa exposição à cloração da água ou ao TTHM (17%; 95% CI, 3-34) baseado em um pequeno número de estudos. A meta-análise também sugere um excesso de risco estatisticamente significante para defeitos septais ventriculares (58%; 95% CI, 21-107), porém com base em apenas três estudos, nos quais se encontrou pouca evidência na relação exposição-resposta. Não foram observadas relações estatisticamente significantes em outras meta-análises e pouca evidência para uma tendência de publicação, com exceção de defeitos no trato urinário e fissura labiopalatal. Apesar de alguns estudos individuais sugerirem uma associação entre subprodutos da desinfecção com cloro e anomalias congênitas, as meta-análises de todos os estudos disponíveis atualmente demonstraram pouca evidência de tal associação.

This study aims to review epidemiologic evidence of the association between exposure to chlorination disinfection by-products (DBPs) and congenital anomalies. All epidemiologic studies that evaluated a relationship between an index of DBP exposure and risk of congenital anomalies were analyzed. For all congenital anomalies combined, the meta-analysis gave a statistically significant excess risk for high versus low exposure to water chlorination or TTHM (17%; 95% CI, 3-34) based on a small number of studies. The meta-analysis also suggested a statistically significant excess risk for ventricular septal defects (58%; 95% CI, 21-107), but based on only three studies, and there was little evidence of an exposure-response relationship. It was observed no statistically significant relationships in the other meta-analyses and little evidence for publication bias, except for urinary tract defects and cleft lip and palate. Although some individual studies have suggested an association between chlorination disinfection by-products and congenital anomalies, meta-analyses of all currently available studies demonstrate little evidence of such association.

O objetivo deste estudo é revisar evidências epidemiológicas da associação entre a exposição a subprodutos da desinfecção com cloro (DBPs) e anomalias congênitas. Todos os estudos epidemiológicos que avaliaram a relação entre o índice de exposição a DBPs e o risco de anomalias congênitas foram analisados. Para todas as anomalias congênitas combinadas, a meta-análise resultou em um risco de excesso estatisticamente significante para alta versus baixa exposição à cloração da água ou ao TTHM (17%; 95% CI, 3-34) baseado em um pequeno número de estudos. A meta-análise também sugere um excesso de risco estatisticamente significante para defeitos septais ventriculares (58%; 95% CI, 21-107), porém com base em apenas três estudos, nos quais se encontrou pouca evidência na relação exposição-resposta. Não foram observadas relações estatisticamente significantes em outras meta-análises e pouca evidência para uma tendência de publicação, com exceção de defeitos no trato urinário e fissura labiopalatal. Apesar de alguns estudos individuais sugerirem uma associação entre subprodutos da desinfecção com cloro e anomalias congênitas, as meta-análises de todos os estudos disponíveis atualmente demonstraram pouca evidência de tal associação.

This study aims to review epidemiologic evidence of the association between exposure to chlorination disinfection by-products (DBPs) and congenital anomalies. All epidemiologic studies that evaluated a relationship between an index of DBP exposure and risk of congenital anomalies were analyzed. For all congenital anomalies combined, the meta-analysis gave a statistically significant excess risk for high versus low exposure to water chlorination or TTHM (17%; 95% CI, 3-34) based on a small number of studies. The meta-analysis also suggested a statistically significant excess risk for ventricular septal defects (58%; 95% CI, 21-107), but based on only three studies, and there was little evidence of an exposure-response relationship. It was observed no statistically significant relationships in the other meta-analyses and little evidence for publication bias, except for urinary tract defects and cleft lip and palate. Although some individual studies have suggested an association between chlorination disinfection by-products and congenital anomalies, meta-analyses of all currently available studies demonstrate little evidence of such association.