Abstract Preterm birth (PTB) is the main condition related to perinatal morbimortality worldwide. The aim of this study was to identify gene-environment interactions associated with spontaneous PTB or its predictors. We carried out a retrospective case-control study including parental sociodemographic and obstetric data as well as newborn genetic variants of 69 preterm and 61 at term newborns born at a maternity hospital from Tucumán, Argentina, between 2005 and 2010. A data-driven Bayesian network including the main PTB predictors was created where we identified gene-environment interactions. We used logistic regressions to calculate the odds ratios and confidence intervals of the interactions. From the main PTB predictors (nine exposures and six genetic variants) we identified an interaction between low neighbourhood socioeconomic status and rs2074351 (PON1, genotype GG) variant that was associated with an increased risk of toxoplasmosis (odds ratio 12.51, confidence interval 95%: 1.71 - 91.36). The results of this exploratory study suggest that structural social disparities could influence the PTB risk by increasing the frequency of exposures that potentiate the risk associated with individual characteristics such as genetic traits. Future studies with larger sample sizes are necessary to confirm these findings.

Introduction. Low birth weight (LBW) is considered a general indicator of health because it is related to complications in the life of a newborn infant and is one of the leading causes of infant mortality. It is a multifactorial indicator, and its determinants include socioeconomic factors. Objective. To assess the impact of economic inequality on the prevalence of LBW by quantifying its differential effect by maternal age, level of maternal education, and level of care. Population and methods. Epidemiological, cross-sectional study that analyzed all births occurred in Argentina between 2001 and 2013 based on data provided by the National Registry of births, corresponding to the Health Statistics and Information Department. The temporal variation in the prevalence of LBW newborn infants (< 2500 grams) and its relation to demographic and socioeconomic indicators were studied. Its association was assessed using logistic regression models. Results. A total of 9 001 960births were included. The prevalence of LBW newborn infants during the 2001 economic crisis increased -6% in 2002 and 7% in 2003- The impact was heterogeneous and higher on public hospitals (|-1;PR|-3; = 1.03) and adolescent mothers (PR=1.07), but no impact was observed on a low level of maternal education (PR= 0.99). Conclusions. The impact of socioeconomic inequality on the prevalence of LBW was significant and heterogeneous, especially on public hospitals and mothers at the extremes of maternal age.

Introducción. El bajo peso al nacer (BPN) es considerado un indicador general de salud por su relación con complicaciones en la vida del recién nacido y por ser una de las primeras causas de mortalidad infantil. Es multifactorial y, entre sus determinantes, se incluyen los socioeconómicos. Objetivo. Evaluar el impacto de la desigualdad económica sobre la prevalencia del BPN, cuantificando el efecto diferencial según edad y educación materna y nivel de atención. Población y métodos. Estudio epidemiológico de diseño transversal, en el cual se analizaron los nacimientos ocurridos en Argentina desde 2001 a 2013 con datos obtenidos del Registro Nacional de los nacimientos, perteneciente a la Dirección de Estadísticas e Información en Salud (DEIS). Se estudió la variación temporal de la prevalencia de recién nacidos con BPN (< 2500 gramos) y su relación con indicadores demográficos y socioeconómicos. Se evaluó su asociación a través de modelos de regresión logística. Resultados. Se incluyeron 9 001 960 nacimientos. Se observó un incremento en la prevalencia de recién nacidos con BPN durante la crisis económica de 2001 -de un 6% en 2002 y un 7% en 2003-. Fue heterogéneo y tuvo mayor impacto en hospitales públicos (razón de prevalencia -RP-= 1,03) y madres adolescentes (RP= 1,07) y ningún impacto sobre la educación materna baja (RP= 0,99). Conclusiones. El impacto de la desigualdad socioeconómica sobre la prevalencia de bajo peso fue significativo y heterogéneo, más importante en hospitales públicos y madres en edades extremas.

ABSTRACT Objective To evaluate prevalence trends of hypospadias in South-America it is essential to perform multicenter and multinational studies with the same methodology. Herein we present systematic data as part of an international multicenter initiative evaluating congenital malformations in South America over a 24-year period. Materials and Methods A nested case-control study was conducted using the Latin American Collaborative Study of Congenital Malformations (ECLAMC), between January 1989 and December 2012. Cases were stratified as isolated (IH) and non-isolated hypospadias (NIH). Global prevalence was calculated and discriminated by country. Associations between birth weight and gestational age, and NIH distribution by associated abnormality and severity of hypospadias, were analyzed. Results A total of 159 hospitals from six countries participated, reporting surveillance on 4.020.384 newborns. A total of 4.537 hypospadias cases were detected, with a global prevalence of 11.3/10.000 newborns. Trend analyses showed in Chile, Brazil and Uruguay a statistically significant increase in prevalence. Analysis of severity and associated anomalies did not to find an association for distal cases, but did for proximal (RR=1.64 [95% CI=1.33-2.03]). Conclusion This is one of only a few Latin American multicenter studies reporting on the epidemiology of hypospadias in South America in the last two decades. Our data adds to evidence suggesting an increase in some countries in the region at different times. There were also variations in prevalence according to severity. This study adds to literature describing associated anomalies at a hospital-based level.

Introduction. Different studies have related familiar and regional adverse social conditions to perinatal outcome (neonatal mortality, low birth weight and prematurity); however, few studies have studied the effect of poverty on congenital anomalies. Objective. To assess the hazard ratio of 25 congenital anomalies and adverse social determinants as per the socioeconomic level of families and regions. Population and methods. Exploratory, case-control study using data from the Latin-American Collaborative Study of Congenital Malformations (Estudio Colaborativo Latinoamericano deMalformaciones Congenitas, ECLAMC). The sample consisted of 3786live newborninfantswitha singlemalformation and 13 344 controls selected among 546 129 births occurred in 39 hospitals from Argentina in the 19922001 period. Both direct and indirect (residence) risks (OR) were estimated, together with the interaction between the individual and residential socioeconomic levels for each of the 25 congenital anomalies. Results.Cleft lip with/without cleft palate (OR= 1.43) and ventricular septal defect (OR= 1.38) showed a significantly higher risk in the lower socioeconomic level. Low socioeconomic levels were significantly associated with a higher frequency of parental sibship (blood relationship); native descent; maternal age younger than 19 years old; more than four pregnancies; a low number of antenatal care visits; and residence in deprived regions. Conclusion. Cleft lip with/without cleft palate and ventricular septal defects were significantly associated with a lower socioeconomic level. Lack of family planning and antenatal care; and exposure to environmental or teratogenic agents may account for these findings.

Introducción. Diferentes trabajos han relacionando condiciones sociales adversas a nivel familiar y regional con resultados perinatales (mortalidad neonatal, bajo peso y prematuridad), sin embargo, pocos estudiaron el efecto de la pobreza sobre anomalías congénitas. Objetivo. Evaluar el riesgo de ocurrencia de 25 anomalías congénitas y determinantes sociales adversos según el nivel socioeconómico de la familia y de la región. Población y métodos. Estudio caso-control exploratorio, en el que se utilizaron datos del Estudio Colaborativo Latinoamericano de Malformaciones Congénitas (ECLAMC). La muestra consistió en 3786 recién nacidos vivos con una única malformación y 13 344 controles, seleccionados entre 546 129 nacimientos, ocurridos en 39 hospitales de Argentina durante el período 1992-2001. Se estimaron los riesgos (OR) directos, indirectos (a través de la región de residencia) y la interacción entre el nivel socioeconómico individual y residencial para cada uno de los 25 defectos congénitos. Resultados. Los defectos labio leporino con/sin paladar hendido (OR= 1,43) y comunicación interventricular (OR= 1,38) mostraron un riesgo significativamente mayor en el nivel socioeconómico más bajo. Los niveles socioeconómicos bajos se asociaron de manera significativa con una mayor frecuencia de consanguinidad parental, ancestros nativos, edad materna menor de 19 años, más de 4 embarazos, bajo número de visitas prenatales y residencia en regiones desfavorables. Conclusión. La fisura labial con o sin paladar hendido y los defectos del tabique interventricular estuvieron asociados significativamente con un nivel socioeconómico más bajo. La falta de planificación familiar, de control prenatal y la exposición a agentes ambientales o teratógenos pueden explicar estos hallazgos.

This is a guide for fieldwork in Population Medical Genetics research projects. Data collection, handling, and analysis from large pedigrees require the use of specific tools and methods not widely familiar to human geneticists, unfortunately leading to ineffective graphic pedigrees. Initially, the objective of the pedigree must be decided, and the available information sources need to be identified and validated. Data collection and recording by the tabulated method is advocated, and the involved techniques are presented. Genealogical and personal information are the two main components of pedigree data. While the latter is unique to each investigation project, the former is solely represented by gametic links between persons. The triad of a given pedigree member and its two parents constitutes the building unit of a genealogy. Likewise, three ID numbers representing those three elements of the triad is the record field required for any pedigree analysis. Pedigree construction, as well as pedigree and population data analysis, varies according to the pre-established objectives, the existing information, and the available resources.

OBJECTIVES: To determine the frequency of smoking and second-hand smoke exposure among pregnant women in Ecuador and to describe the sociodemographic profiles associated with these perinatal risk factors. METHODS: A cross-sectional descriptive study using a survey of women 18-46 years of age who were more than three months pregnant and attended follow-up consultations in seven maternity clinics in six cities in Ecuador between October 2004 and September 2005. Demographics and environmental exposure (independent variables) data and their relationship to cigarette smoking and secondhand-smoke exposure were analyzed. RESULTS: Of the 746 women studied, 53.3% had smoked occasionally, and 4.3%, regularly; of these, 75% had quit smoking before or during pregnancy. Of the respondents, 12.9% were frequently or always exposed to secondhand smoke indoors. Having more education (11 or more years), being in the middle or upper socioeconomic classes, being Caucasian, and it being considered acceptable for women in the community to smoke were significantly and directly associated with cigarette smoking (P < 0.001). Overall, 12.9% of women were being exposed to secondhand smoke and this was significantly associated with being single and cohabiting with smokers or employees connected to the tobacco industry (P < 0.001). CONCLUSIONS: Specific measures must be designed and implemented to not only encourage smoking cessation during pregnancy, but also to prevent women of reproductive age from taking up smoking and to limit smoking in the home environment.

OBJETIVOS: Determinar la frecuencia de tabaquismo y exposición ambiental al humo de tabaco en mujeres embarazadas de Ecuador y describir los perfiles sociodemográficos asociados con esos factores de riesgo perinatal. MÉTODOS: Estudio descriptivo transversal mediante una encuesta aplicada a mujeres de 18 a 46 años con más de 3 meses de embarazo que asistieron entre octubre de 2004 y septiembre de 2005 a sus consultas de seguimiento en siete servicios de maternidad de seis ciudades de Ecuador. Se analizaron los datos demográficos y de exposición medioambiental (variables independientes) y su relación con el hábito de fumar cigarrillos y la exposición ambiental al humo de tabaco. RESULTADOS: De las 746 mujeres analizadas, 53,3% había fumado ocasionalmente y 4,3% había fumado habitualmente; de estas, 75,0% había dejado de fumar antes o durante el embarazo. De las encuestadas, 12,9% estuvo expuesta con frecuencia o siempre al humo de tabaco en ambientes cerrados. Tener mayor educación (11 años o más) y un nivel socioeconómico medio o alto, ser caucásica y considerar aceptable que las mujeres de su comunidad fumen se asoció significativa y directamente con el hábito de fumar cigarrillos (P < 0,001). En general, 12,9% de las mujeres estuvo expuesta al humo de tabaco y esto se asoció significativamente con ser soltera y cohabitar con fumadores o trabajadores vinculados con la industria del tabaco (P < 0,001). CONCLUSIONES: Se deben diseñar e implementar medidas específicas dirigidas no solo a estimular el abandono de este hábito en las embarazadas, sino también a prevenir que las mujeres en edad reproductiva comiencen a fumar y controlar el entorno fumador en el hogar.