Infant morbidity and mortality attributable to prenatal smoking in Chile.

OBJECTIVE: To estimate annual infant morbidity and mortality attributable to prenatal smoking in Chile during 2008-2012. METHODS: Population-attributable fractions (PAFs) for several infant outcomes were calculated based on previous study estimates of prenatal smoking prevalence and odds ratios associated with exposure (prenatal smoking relative to non-prenatal smoking). Prenatal smoking-attributable infant morbidity and mortality cases were calculated by multiplying the average annual number of morbidity and mortality cases registered in Chile during 2008-2012 by the corresponding PAF. RESULTS: PAFs for 1) births ≤ 27 weeks; 2) births at 28-33 weeks; 3) births at 34-36 weeks; and 4) full-term low-birth-weight infants were 12.3%, 10.6%, 5.5%, and 27.4% respectively. PAFs for deaths caused by preterm-related causes and deaths caused by sudden infant death syndrome were 11.9% and 40.0% respectively. Annually, 2 054 cases of preterm-birth and full-term low-birth-weight (1 in 9 cases), 68 deaths caused by preterm-related causes (1 in 8 cases), and 26 deaths caused by sudden infant death syndrome (1 in 3 cases) were attributable to prenatal smoking. CONCLUSIONS: In Chile, infant morbidity and mortality attributable to prenatal smoking are unacceptably high. Comprehensive individual and population-based interventions for tobacco control should be a public health priority in the country, particularly among female adolescents and young women who will be the mothers of future generations.

Oxytocin for preventing postpartum haemorrhage (PPH) in non-facility birth settings.

BACKGROUND: Postpartum haemorrhage (PPH) is the single leading cause of maternal mortality worldwide. Most of the deaths associated with PPH occur in resource-poor settings where effective methods of prevention and treatment - such as oxytocin - are not accessible because many births still occur at home, or in community settings, far from a health facility. Likewise, most of the evidence supporting oxytocin effectiveness comes from hospital settings in high-income countries, mainly because of the need of well-organised care for its administration and monitoring. Easier methods for oxytocin administration have been developed for use in resource-poor settings, but as far as we know, its effectiveness has not been assessed in a systematic review. OBJECTIVES: To assess the effectiveness and safety of oxytocin provided in non-facility birth settings by any way in the third stage of labour to prevent PPH. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register, the WHO International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov (12 November 2015), and reference lists of retrieved reports. SELECTION CRITERIA: All published, unpublished or ongoing randomised or quasi-randomised controlled trials comparing the administration of oxytocin with no intervention, or usual/standard care for the management of the third stage of labour in non-facility birth settings were considered for inclusion.Quasi-randomised controlled trials and randomised controlled trials published in abstract form only were eligible for inclusion but none were identified. Cross-over trials were not eligible for inclusion in this review. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for eligibility, assessed risk of bias and extracted the data using an agreed data extraction form. Data were checked for accuracy. MAIN RESULTS: We included one cluster-randomised trial conducted in four rural districts in Ghana that randomised 28 community health officers (CHOs) (serving 2404 potentially eligible pregnant women) to the intervention group and 26 CHOs (serving 3515 potentially eligible pregnant women) to the control group. Overall, the trial had a high risk of bias. CHOs delivered the intervention in the experimental group (injection of 10 IU (international units) of oxytocin in the thigh one minute following birth using a prefilled, auto-disposable syringe). In the control group, CHOs did not provide this prophylactic injection to the women they observed. CHOs had no midwifery skills and did not in any way manage the birth. All other CHO activities (outcome measurement, data collection, and early treatment and referral when necessary) were identical across the control and oxytocin CHOs.Although only one of the nine cases of severe PPH (blood loss greater or equal to 1000 mL) occurred in the oxytocin group, the effect estimate for this outcome was very imprecise and it is uncertain whether the intervention prevents severe PPH (risk ratio (RR) 0.16, 95% confidence interval (CI) 0.02 to 1.30; 1570 women (very low-quality evidence)). Similarly, because of the lack of cases of severe maternal morbidity (e.g. uterine rupture) and maternal deaths, it was not possible to obtain effect estimates for those outcomes (both very low-quality evidence).Oxytocin compared with the control group decreased the incidence of PPH (> 500 mL) in both our unadjusted (RR 0.48, 95% CI 0.28 to 0.81; 1569 women) and adjusted (RR 0.49, 95% CI 0.27 to 0.90; 1174 women (both low-quality evidence)) analyses. There was little or no difference between the oxytocin and control groups on the rates of transfer or referral of the mother to a healthcare facility (RR 0.72, 95% CI 0.34 to 1.56; 1586 women (low-quality evidence)), stillbirths (RR 1.27, 95% CI 0.67 to 2.40; 2006 infants (low-quality evidence)); andearly infant deaths (0 to three days) (RR 1.03, 95% CI 0.35 to 3.07; 1969 infants (low-quality evidence)). There were no cases of needle-stick injury or any other maternal major or minor adverse event or unanticipated harmful event. There were no cases of oxytocin use during labour.There were no data reported for some of this review's secondary outcomes: manual removal of placenta, maternal anaemia, neonatal death within 28 days, neonatal transfer to health facility for advanced care, breastfeeding rates. Similarly, the women's or the provider's satisfaction with the intervention was not reported. AUTHORS' CONCLUSIONS: It is uncertain if oxytocin administered by CHO in non-facility settings compared with a control group reduces the incidence of severe PPH (>1000 mL), severe maternal morbidity or maternal deaths. However, the intervention probably decreases the incidence of PPH (> 500 mL).The quality of the one trial included in this review was limited because of the risk of attrition and recruitment biases related to limitations in the follow-up of pregnant women in both arms of the trials and some baseline imbalance on the size of babies at birth. Additionally, there was serious imprecision of the effect estimates for most of the primary outcomes mainly because of the size of the trial, very few or no events and CIs around both relative and absolute estimates of effect that include both appreciable benefit and appreciable harm.Although the trial presented data both for primary and secondary outcomes, it seemed to be underpowered to detect differences in the primary outcomes that are the ones more relevant for making judgments about the potential applicability of the intervention in other settings (especially severe PPH).Therefore, taking into account the extreme setting where the intervention was implemented, the limited role of the CHO in the trial and the lack of power for detecting effects on primary (relevant) outcomes, the applicability of the evidence found seems to be rather limited.Further well-executed and adequately-powered randomised controlled trials assessing the effects of using oxytocin in pre-filled injection devices or other new delivery systems (spray-dried ultrafine formulation of oxytocin) on severe PPH are urgently needed. Likewise, other important outcomes like possible adverse events and acceptability of the intervention by mothers and other community stakeholders should also be assessed.

[Rising infant mortality in down syndrome in Chile from 1997 to 2013]. / Aumento de la mortalidad infantil en niños con síndrome de Down: Chile 1997-2013.

BACKGROUND: Down syndrome (DS) is associated with higher child mortality especially due to cardiac malformations. AIM: To describe the trend in Chilean infant mortality in DS in the period 1997-2013 as compared to the general population without DS. MATERIAL AND METHODS: Raw data on infant deaths were extracted from the yearbooks of vital statistics of the National Institute of Statistics. The mortality risk associated to DS, relative to population without DS was estimated. RESULTS: There were 456 deaths in infants with DS during the study period (59 early neonatal deaths, 70 late neonatal deaths and 327 post-neonatal deaths). The trend in infant mortality rate in DS was ascending (r: 0.53, p = 0.03), with an average annual percentage change of 4.6% (95% confidence interval (CI) 0.4-9.0%; p < 0.01). Compared to the population without DS, the risk of early neonatal death was lower in DS (Odds ratio (OR) 0.14, 95% CI 0.11-0.19; p < 0.01) whereas the risk of post-neonatal death was higher (OR 4.74, 95% CI 3.85-5.85; p < 0.01). CONCLUSIONS: Infant mortality in Down syndrome has an increasing trend. We postulate that these children are not accessing timely cardiac surgery, the main therapeutic tool to reduce the death risk in the first year of life.

Preventive letter: doubling the return rate after gestational diabetes mellitus.

To measure the impact of a "Preventive Letter" designed to encourage the return of gestational diabetes mellitus (GDM) mothers to follow up visit after delivery, in the context of a worldwide concern about low return rates after delivery of these patients. Mothers with GDM require medical evaluation and an oral glucose tolerance test (OGTT) 6 weeks after delivery, in order to: [a] confirm remission of GDM and [b] provide advice on the prevention of type 2 diabetes. In the year 2003 we developed a "Preventive Letter", containing three aspects: [a] current treatment, [b] suggested management during labor, and [c] a stapled laboratory order for OGTT to be performed 6 weeks after delivery. The return rate after delivery was assessed in two groups of GDM mothers: [a] "Without Preventive Letter" (n = 253), and "With Preventive Letter" (n = 215). Both groups, similar with respect to age (33.0 ± 5.4 and 32.3 ± 4.9 years respectively, p = 0.166) and education time (14.9 ± 1.8 and 15.0 ± 1.8 years respectively, p = 0.494), showed a significant difference in the 1-year return rate after delivery, as assessed by the Kaplan-Meier test: 32.0 % for the group "Without Preventive Letter", and 76.0 % for the group "With Preventive Letter" (p < 0.001). The 1-year return rate after delivery of GDM mothers was 2.4 times higher in the group "With Preventive Letter" than in the group without it. We believe that this low-cost approach could be useful in other institutions caring for pregnant women with diabetes.

[Women age as a risk factor for maternal, fetal, neonatal and infant mortality]. / La edad de la mujer como factor de riesgo de mortalidad materna, fetal, neonatal e infantil.

BACKGROUND: Adolescent pregnancy and advanced maternal age are associated with increased risk for maternal, perinatal and infant death. However, the maternal age with the lowest reproductive risk has not been established. AIM: To determine the range of maternal age with the lowest reproductive risk. MATERIAL AND METHODS: A population-based study (2005-2010) was performed analyzing raw data from vital statistics yearbooks of the National Institute of Statistics of Chile. The association of maternal, fetal, neonatal and infant mortality with maternal age was analyzed. The latter was stratified in quinquenniums, between ages 10 and 54 years. Maternal, fetal, neonatal and infant mortality rates were calculated for each quinquennium. The lowest rate was selected as a control group for risk analysis, which was estimated according to Odds Ratio with 95% confidence intervals. RESULTS: Women of 20-29, 25-34 and under 30 years, had the lowest rate of fetal, neonatal/infant and maternal death, respectively. Women aged 45-49 years had the higher rate of maternal, fetal, neonatal and infant mortality. The risk of fetal, neonatal and infant mortality doubled from 40-44 years onwards, and maternal mortality from the age of 30-34 years. CONCLUSIONS: Our results suggest that the maternal age range with the lesser general reproductive risk is between 20-29 years. This finding should be considered in future studies of reproductive risk and for an appropriate counseling about conception.

A population-based cohort study of breastfeeding according to gestational age at term delivery.

OBJECTIVE: Because breastfeeding is the optimal form of infant feeding, this study was conducted to determine the effect of gestational age on breastfeeding in term infants. STUDY DESIGN: A retrospective population-based cohort study of singleton/twin hospital births was conducted in Ontario, Canada between April 1, 2009, and March 31, 2010. Multivariate logistic regression was used to determine the adjusted effect of gestational age on breastfeeding. RESULTS: Our study population comprised 92,364 infants, of whom 80,297 (86.9%) were exclusively or partially breastfed at the time of hospital discharge. Multivariate logistic regression analyses demonstrated that early-term infants had lower odds of being breastfed compared with infants born at 41 weeks gestation (40 weeks: aOR, 0.93; 95% CI, 0.86-0.99; 39 weeks: aOR, 0.87; 95% CI, 0.81-0.93; 38 weeks: aOR, 0.81; 95% CI, 0.75-0.88; 37 weeks: aOR, 0.74; 95% CI, 0.67-0.82). CONCLUSION: Using a population-based approach, we found that infants born at 40, 39, 38, and 37 weeks gestation had increasingly lower odds of being breastfed compared with infants born at 41 weeks. Clinicians need to be made aware of the differences in outcomes of infants delivered at early and late term, so that appropriate breastfeeding support can be provided to women at risk for not breastfeeding.

[Odds ratio: theoretical and practical issues]. / Odds ratio: aspectos teóricos y prácticos.

Odds Ratio (OR) is an effect measure frequently used to communicate results of health research. Mathematically, OR is the quotient between two odds, being odds an alternative way to express possibility of occurrence of an outcome or presence of an exposition. From a methodological perspective, OR can be calculated from prospective, retrospective and cross-sectional designs, and under certain conditions it can replace the Relative Risk. Based on a series of questions and examples, this article explains theoretical and methodological grounds underlying the concept of OR, in order to facilitate its interpretation for clinicians and researchers.

Maternal and perinatal outcomes of a venous thromboembolism high-risk cohort using a multidisciplinary treatment approach.

OBJECTIVE: To evaluate the maternal and perinatal outcomes in a cohort of pregnant women at high risk of venous thromboembolism (VTE). METHODS: Women at high risk of VTE were evaluated in a multidisciplinary program using a complete diagnostic workup, and specific prophylactic or therapeutic treatment. RESULTS: Women were considered at high risk of VTE in 57% (85/148) because of prior (75) or current (10) thromboembolism, and in 27% (40/148) of the cases due to adverse obstetric history. Thrombophilia was diagnosed in 57% of the cases (85/148), either in patients with previous thromboembolism (48%, 41/85) or without a history of thrombosis (70%, 44/63). The most common thrombophilia was antiphospholipid syndrome in 34% (29/85) of the cases. Under respective prophylactic or therapeutic treatment, there were no VTE during pregnancy (0%, 0/148), whereas four events occurred during the puerperium (3%, 4/148). An adverse obstetric outcome was present in 5% (7/148) of all pregnancies, with four early spontaneous abortions (3%, 4/148) and three late miscarriages (2%, 3/148). CONCLUSION: Pregnant women at high risk of VTE can be effectively managed using a risk-adapted treatment. Our results support prospective enrollment and a multidisciplinary assessment of VTE in high-risk pregnant women.

Non-Destructive Assessment of the Dynamic Elasticity Modulus of Eucalyptus nitens Timber Boards.

Eucalyptus nitens is a fast-growing wood species with a relevant presence in countries like Australia and Chile. The sustainable construction goals have driven the search of structural applications for Eucalyptus nitens; however, this process has been complicated due to the defects usually presented in these timber boards. This study aims to evaluate the dynamic elasticity modulus (Exd) of Eucalyptus nitens timber boards through non-destructive vibration-based tests. Thirty-six timber boards with different levels of knots and cracks were instrumented and tested in a simply supported condition by measuring longitudinal and transverse vibrations. In the first stage, the Exd was calculated globally through simplified normative formulas. Then, in a second stage, the local variability of the Exd was estimated using operational modal analysis (OMA), finite element numerical simulations (FEM), and regional sensitivity analysis (RSA). The positive correlation found between the global static modulus of elasticity and Exd suggests that non-destructive techniques could be used as a reliable and fast alternative for the assessment of bending stiffness. Finally, the proposed method to estimate the local variability of Exdt based on the combination of OMA, FEM, and RSA techniques was useful to improve the structural selection process of timber boards for lightweight social housing floors.

Non-hormonal interventions for hot flushes in women with a history of breast cancer.

BACKGROUND: Hot flushes are common in women with a history of breast cancer. Hormonal therapies are known to reduce these symptoms but are not recommended in women with a history of breast cancer due to their potential adverse effects. The efficacy of non-hormonal therapies is still uncertain. OBJECTIVES: To assess the efficacy of non-hormonal therapies in reducing hot flushes in women with a history of breast cancer. SEARCH STRATEGY: We searched the Cochrane Breast Cancer Group Specialised Register, CENTRAL (The Cochrane Library), MEDLINE, EMBASE, LILACS, CINAHL, PsycINFO (August 2008) and WHO ICTRP Search Portal. We handsearched reference lists of reviews and included articles, reviewed conference proceedings and contacted experts. SELECTION CRITERIA: Randomized controlled trials (RCTs) comparing non-hormonal therapies with placebo or no therapy for reducing hot flushes in women with a history of breast cancer. DATA COLLECTION AND ANALYSIS: Two authors independently selected potentially relevant studies, decided upon their inclusion and extracted data on participant characteristics, interventions, outcomes and the risk of bias of included studies. MAIN RESULTS: Sixteen RCTs met our inclusion criteria. We included six studies on selective serotonin (SSRI) and serotonin-norepinephrine (SNRI) reuptake inhibitors, two on clonidine, one on gabapentin, two each on relaxation therapy and homeopathy, and one each on vitamin E, magnetic devices and acupuncture. The risk of bias of most studies was rated as low or moderate. Data on continuous outcomes were presented inconsistently among studies, which precluded the possibility of pooling the results. Three pharmacological treatments (SSRIs and SNRIs, clonidine and gabapentin) reduced the number and severity of hot flushes. One study assessing vitamin E did not show any beneficial effect. One of two studies on relaxation therapy showed a significant benefit. None of the other non-pharmacological therapies had a significant benefit. Side-effects were inconsistently reported. AUTHORS' CONCLUSIONS: Clonidine, SSRIs and SNRIs, gabapentin and relaxation therapy showed a mild to moderate effect on reducing hot flushes in women with a history of breast cancer.

Is ursodeoxycholic acid effective for intrahepatic cholestasis of pregnancy?

Intrahepatic cholestasis of pregnancy is a condition associated with fetal morbidity and mortality. Ursodeoxycholic acid has been proposed as a treatment alternative, but its use remains controversial. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified three systematic reviews including eight randomized trials. We combined the evidence using meta-analysis and generated a summary of findings table following the GRADE approach. We concluded ursodeoxycholic acid reduces prematurity risk and need for admission in neonatal intensive care units. It might also reduce maternal pruritus.

La colestasia intrahepática del embarazo es una condición propia de la gestación y se asocia a mayor morbilidad y mortalidad perinatal. Dentro de las alternativas terapéuticas se ha propuesto el uso del ácido ursodeoxicólico, sin embargo su beneficio sigue siendo controvertido. Utilizando la base de datos Epistemonikos, la cual es mantenida mediante búsquedas en 30 bases de datos, identificamos tres revisiones sistemáticas que en conjunto incluyen ocho estudios aleatorizados. Realizamos un metanálisis y tablas de resumen de los resultados utilizando el método GRADE. Concluimos que el uso de ácido ursodeoxicólico en la colestasia intrahepática del embarazo podría reducir el riesgo de prematurez y de necesidad de hospitalización del recién nacido en unidad de cuidado intensivo. También podría disminuir el prurito materno.

Desaceleración en la reducción de la mortalidad materna en Chile impide alcanzar el 5° Objetivo de Desarrollo del Milenio / Slowdown in reducing maternal mortality in Chile prevents reach the 5th Millennium Development Goal

Antecedentes: en Chile, a pesar de la importante reducción de la mortalidad materna en la década de los 90, los avances distan de los objetivos comprometidos. Objetivos: analizar la tendencia de la razón de mortalidad materna (RMM) en Chile desde 1990 al 2015 y de factores epidemiológicos que afectan el cumplimiento del 5° Objetivo del Mileno (5°OM). Métodos: estudio observacional a nivel nacional. Analizamos la tendencia del cambio porcentual anual promedio (CPAP) y puntos de inflexión de la RMM junto con la evolución de los nacimientos, muertes maternas y sus causas. Además, analizamos los nacimientos por edad y la distribución de la razón de mortalidad materna por edad y por causa de muerte materna. Resultados: en Chile la RMM se redujo un 61% entre 1990 y 2015, con una inflexión desde el 2001 (IC 95% 1997 a 2004) demostrando dos periodos: 1990-2001 (CPAP -6,97%; IC 95% -8,63 a -5,29) y 2001-2015 (CPAP -0,66%; IC 95% -2,40 a 1,10). En el segundo período la tasa de natalidad disminuyó con menor pendiente, los nacimientos de madres de 15-29 años disminuyeron, mientras que en los otros estratos de edad los nacimientos aumentaron. En ambos períodos las primeras causas de muerte fueron hipertensión arterial, enfermedades concurrentes y aborto. En el segundo período la muerte materna por hipertensión arterial y aborto se redujo, mientras que por enfermedades concurrentes aumentó. Conclusiones: en Chile la RMM es estacionaria desde el 2001 y se asocia a cambios en la distribución en la edad materna y causas de muerte. (AU)

Background: in Chile, despite the significant reduction in maternal mortality in the 1990s, the advances are far from the committed objectives. Aim: To analyze trends of the maternal mortality ratio (MMR) in Chile from 1990 to 2015 and epidemiologic factors that threaten the5th Millennium Goal. Methods: an observational study at the country level. We performed a trend analysis of the average annual percent change (AAPC) and models for joint point analyses for MMR, births, maternal deaths and their causes. In addition, we assessed the Odds Ratios for births by maternal age and the distribution of the maternal mortality rate by maternal age and main death causes. Results: in Chile, a reduction of 61% in MMR was observed from 1990 to 2015 with a trend join point in 2001 (CI 95% 1997 to 2004) indicating two periods: 1990-2001 (AAPC -6.97%; 95% CI -8.63 to -5.29) and 2001-2015 (AAPC - 0.66%; 95% CI -2.4 to 1.10). In the second period the birth rate decreased with a lower slope, the births of mothers in the age group 15-29 decreased, while in the other age groups the births increased. In both periods, main maternal death causes were hypertension, concurrent illness, and abortion. In the second period, maternal deaths associated to hypertension and abortion decreased, whereas deaths associated to concurrent illness increased. Conclusions: in Chile, MMR has been stationary since 2001 and is associated with changes in the distribution of maternal age and causes of death.(AU)

Maternal hypertriglyceridemia: A link between maternal overweight-obesity and macrosomia in gestational diabetes.

OBJECTIVE: Infants born from overweight and obese mothers with glucose-controlled gestational diabetes (GDM) tend to be large-for-gestational age (LGA). It is hypothesized that this is due to an excessive rise in maternal triglyceride levels. METHODS: Two-hundred and seventy nine singleton GDM pregnancies were divided into three groups according to prepregnancy BMI: normal weight (BMI = 20-24.9; n = 128), overweight (BMI = 25-29.9; n = 105), and obese (BMI ≥ 30; n = 46). Individual z-scores (ZS) of maternal triglycerides and of newborn weight (NWZS) were calculated as deviations from published 50th percentiles. Mean z-scores (MZS) were the average of triglyceride ZSs. MZS of triglycerides, HbA1c and NWZS were compared. Variables are expressed as mean ± SD. RESULTS: In the three groups respectively: LGA (%) = 10.1%, 19.0% and 30.4% (P = 0.015). Birth weight (g) = 3274.2 ± 501.3, 3342.4 ± 620.2 and 3366.3±644.7 (RSPEARMAN = 0.111, P = 0.027). HbA1c (%) = 5.2 ± 0.39, 5.3 ± 0.50 and 5.4 ± 0.47 (P = NS). Triglyceride MZS = 1.20 ± 1.13, 1.52 ± 1.37 and 1.62 ± 1.42 (RSPEARMAN = 0.116, P = 0.024). Correlations between triglyceride MZS and NWZS were, respectively: r = 0.12 (P = NS), r = 0.42 (P <0.001), and r = 0.47 (P < 0.001). CONCLUSIONS: In overweight and obese GDM mothers, maternal triglycerides are partially responsible for LGA infants despite good maternal glucose control during pregnancy.

Mayor mortalidad materna por aborto en Cuba que en Chile, 2000-2015 / Higher maternal mortality from abortion in Cuba than in Chile, 2000-2015

RESUMEN Antecedentes: La muerte materna por aborto inseguro es un severo problema de salud pública, países con leyes de aborto liberales tendrían menor riesgo de aborto inseguro y de mortalidad por aborto. Cuba tiene una legislación que no penaliza el aborto inducido, mientras en Chile es ilegal en todos los casos hasta su reciente despenalización en 3 causales. Objetivo: Se postula que Cuba tendría una menor mortalidad materna por aborto que Chile, por lo que se propone comparar la evolución de la razón de mortalidad materna por aborto entre ambos países, en el período 2000-2015. Material y Método: Los datos crudos de muertes asociadas al aborto y nacidos vivos se obtienen de las bases de datos de estadísticas vitales de ambos países. La oportunidad relativa de muerte se estima según Odds Ratio (OR) con intervalo de confianza del 95% (IC 95%) de las razones de mortalidad materna. Resultados: La razón de muerte materna asociada al aborto fue mayor en Cuba que en Chile (OR: 1,91; IC 95%: 1,331 a 2,739; p=0,0004). Se observa una tendencia al descenso en Cuba y mientras no se observan cambios en Chile. Conclusiones: Contrario a lo postulado basado en las diferentes legislaciones de ambos países, en el período 2000-2015, Cuba presentó mayor razón de mortalidad materna asociada al aborto que Chile. Se comentan posibles condicionantes de la diferencia encontrada.

ABSTRACT Background: Maternal death due to unsafe abortion is a severe public health problem; countries with liberal abortion laws would have a lower risk of unsafe abortion and abortion mortality. Cuba has a legislation that does not penalize induced abortion, while in Chile it is illegal in all cases until its recent decriminalization in 3 grounds. Objective: It is postulated that Cuba would have a lower maternal mortality due to abortion than Chile, for which purpose it is proposed to compare the evolution of the maternal mortality by abortion between both countries, in the period 2000-2015. Material and Method: Raw data on deaths associated with abortion and live births are obtained from the vital statistics databases of both countries. The relative chance of death is estimated according to the Odds Ratio (OR) with a 95% confidence interval (95% CI) of the maternal mortality. Results: The maternal death rate associated with abortion was higher in Cuba than in Chile (OR: 1.91, 95% CI: 1.331 to 2.739; p = 0.0004). A downward trend is observed in Cuba and without changes in Chile. Conclusions: Contrary to the postulate based on the different legislations of both countries, in the period 20002015, Cuba had a higher maternal mortality associated with abortion than Chile. Possible conditioning factors of the difference found are discussed.

Utilidad de factores pronósticos antenatales en pacientes con hernia diafragmática congénita aislada / Usefulness of antenatal prognostic factors in patients with hernia congenital diaphragmatic isolated

La Hernia Diafragmática Congénita (HDC) corresponde a una malformación del diafragma por la cual los órganos abdominales protruyen hacia la cavidad torácica durante el desarrollo intrauterino. Los recién nacidos afectados presentan grados variables de insuficiencia respiratoria e hipertensión pulmonar, asociándose a una alta morbilidad y mortalidad. Materiales y métodos: Se revisaron los casos de HDC controlados en los períodos pre y post-natal en el Hospital Clínico UC durante el período 2012-2016. Se analizaron los resultados perinatales según distintos factores pronósticos. Resultados: Fueron analizadas 26 embarazadas con diagnóstico de HDC. La sobrevida global fue de un 77% (20/26). La mortalidad global de las pacientes con herniación hepática fue de un 45% (5/11) versus 7% (1/15) en los fetos con hígado no herniado. La mortalidad neonatal fue de un 14% (3/21) en las pacientes con la relación pulmón cabeza (LHR), (observado/ esperado) o/e ≥ a 45% y 60% (3/5) cuando el LHR o/e es < 45%. De las pacientes con LHR o/e ≥ 45%, la necesidad de ECMO fue de un 33% (8/21) mientras que un LHR o/e < 45% fue de un 20% (1/5). Conclusión: La obtención antenatal de un LHR o/e ≥ 45% y ausencia de herniación hepática, son buenos predictores de sobrevida neonatal. La medición de LHR o/e no es capaz de discriminar que pacientes desarrollarán morbilidad respiratoria grave, por lo que debemos buscar nuevos y mejores modelos que permitan seleccionar que pacientes requerirán nacer en un centro con disponibilidad de terapias de soporte vital avanzado como el ECMO neonatal. (AU)

Congenital Diaphragmatic Hernia (CDH) is a malformation of the diaphragm muscle in which the abdominal organs protrude into the thoracic cavity during intrauterine development. Affected newborns have varying degrees of respiratory failure and pulmonary hypertension, associated with high morbidity and mortality. Materials and methods: Controlled HDC cases were reviewed in the pre and post-natal periods at the Clinical Hospital UC during the period 2012-2016. Perinatal results were analyzed according to different prognostic factors. Results: During the 2012-2016 period, 26 pregnant women with a diagnosis of CDH were monitored. The overall mortality of patients with hepatic herniation was 45% (5/11) versus 7% (1/15) in fetuses with a non-herniated liver. Neonatal mortality was 14% (3/21) in patients with o/e (observed/expected) LHR ≥ 45% and 60% (3/5) when the o/e LHR <45%. Of the patients with o/e LHR ≥ 45%, the need for ECMO was 33% (8/21), while a LHR o/e <45% was 20% (1/5). Conclusion: An o/e LHR ≥ 45% and absence of hepatic herniation are good predictors of neonatal survival. The o/e LHR measurement is not capable of identifying which patients will develop severe respiratory morbidity, so we must explore new and better models that allow us to select patients who need to give birth in centers with available advanced life support therapies, such as neonatal ECMO. (AU)

Infant morbidity and mortality attributable to prenatal smoking in Chile / Morbilidad y mortalidad del lactante atribuible al tabaquismo prenatal en Chile / Morbidade e mortalidade infantis atribuíveis ao tabagismo durante a gestação no Chile

ABSTRACT Objective To estimate annual infant morbidity and mortality attributable to prenatal smoking in Chile during 2008−2012. Methods Population-attributable fractions (PAFs) for several infant outcomes were calculated based on previous study estimates of prenatal smoking prevalence and odds ratios associated with exposure (prenatal smoking relative to non-prenatal smoking). Prenatal smoking-attributable infant morbidity and mortality cases were calculated by multiplying the average annual number of morbidity and mortality cases registered in Chile during 2008-2012 by the corresponding PAF. Results PAFs for 1) births ≤ 27 weeks; 2) births at 28-33 weeks; 3) births at 34-36 weeks; and 4) full-term low-birth-weight infants were 12.3%, 10.6%, 5.5%, and 27.4% respectively. PAFs for deaths caused by preterm-related causes and deaths caused by sudden infant death syndrome were 11.9% and 40.0% respectively. Annually, 2 054 cases of preterm-birth and full-term low-birth-weight (1 in 9 cases), 68 deaths caused by preterm-related causes (1 in 8 cases), and 26 deaths caused by sudden infant death syndrome (1 in 3 cases) were attributable to prenatal smoking. Conclusions In Chile, infant morbidity and mortality attributable to prenatal smoking are unacceptably high. Comprehensive individual and population-based interventions for tobacco control should be a public health priority in the country, particularly among female adolescents and young women who will be the mothers of future generations.

RESUMEN Objetivo Calcular las tasas anuales de morbilidad y mortalidad de lactantes atribuibles al tabaquismo prenatal en Chile entre los años 2008 y 2012. Métodos Se calcularon las fracciones atribuibles a la población (FAP) correspondientes a diferentes resultados de salud en lactantes tomando como base la prevalencia estimativa del tabaquismo prenatal y las razones de posibilidad asociadas a la exposición (tabaquismo prenatal frente a tabaquismo no prenatal) calculadas en estudios previos. Los casos de mortalidad y morbilidad de lactantes atribuibles al tabaquismo prenatal se calcularon multiplicando el promedio anual de casos de morbilidad y mortalidad registrados en Chile entre los años 2008 y 2012 por la FAP correspondiente. Resultados Las FAP para los lactantes nacidos 1) a las 27 semanas o menos de gestación; 2) de 28 a 33 semanas de gestación; 3) de 34 a 36 semanas de gestación; y 4) al término de la gestación, pero con peso bajo al nacer, fueron de 12,3%, 10,6%, 5,5% y 27,4%, respectivamente. Las FAP correspondientes a las muertes por causas relacionadas con el nacimiento prematuro y las muertes por síndrome de muerte súbita del lactante fueron de 11,9% y 40,0%, respectivamente. Al año, 2 054 casos de bebés prematuros y de bebés nacidos con peso bajo al término de la gestación (1 de 9 casos), 68 muertes por causas relacionadas con el período prenatal (1 de 8 casos) y 26 muertes causadas por el síndrome de muerte súbita del lactante (1 de 3 casos) fueron atribuibles al tabaquismo prenatal. Conclusiones En Chile, las tasas de morbilidad y mortalidad de lactantes atribuibles al tabaquismo prenatal son inadmisiblemente altas. En el país, las intervenciones integrales para el control del tabaco a nivel individual y poblacional deben ser una prioridad de salud pública, particularmente en las mujeres adolescentes y jóvenes que serán las madres de las generaciones futuras.

RESUMO Objetivo Estimar a morbidade e a mortalidade infantis anuais atribuíveis ao tabagismo durante a gestação no Chile em 2008-2012. Métodos As frações atribuíveis populacionais (PAFs) para vários desfechos infantis foram calculadas com base em estimativas de estudos anteriores da prevalência do tabagismo durante a gestação e razões de possibilidades associadas à exposição (tabagismo durante a gestação relativo ao tabagismo fora da gestação). Os casos de morbidade e mortalidade infantis atribuíveis ao tabagismo durante a gestação foram calculados multiplicando-se o número médio anual de casos de morbidade e mortalidade registrados no Chile em 2008-2012 pela PAF correspondente. Resultados As PAFs para 1) recém-nascidos ≤ 27 semanas, 2) recém-nascidos com 28-33 semanas, 3) recém-nascidos com 34-36 semanas e 4) recém-nascidos de termo com baixo peso foram 12,3%, 10,6%, 5,5% e 27,4%, respectivamente. As PAFs para mortes devidas a causas relacionadas à prematuridade e mortes devidas à síndrome de morte súbita do recém-nascido foram 11,9% e 40,0%, respectivamente. Anualmente, 2.054 casos de recém-nascidos prematuros e de termo com baixo peso (1 em 9 casos), 68 mortes devidas a causas relacionadas à assistência pré-natal (1 em 8 casos) e 26 mortes devidas à síndrome de morte súbita do recém-nascido (1 em 3 casos) foram atribuíveis ao tabagismo durante a gestação. Conclusões No Chile, a morbidade e a mortalidade infantis atribuíveis ao tabagismo durante a gestação são inadmissivelmente elevadas. Amplas intervenções individuais e populacionais para o controle do tabagismo devem ser uma prioridade de saúde pública no país, sobretudo em adolescentes e jovens que serão mães das futuras gerações.

Manejo de la pancreatitis aguda litiásica en la embarazada / Management of acute lithiasic pancreatitis in pregnant women

Resumen: La pancreatitis aguda (PA) es una patología poco frecuente durante el embarazo, siendo la colelitiasis una de sus principales etiologías y Chile uno de los países con más altas prevalencias de colelitiasis en el mundo. Esta patología clásicamente ha reportado altas tasas de mortalidad materno-fetal, así como también riesgo de morbilidad fetal. Sin embargo, gracias a los avances en terapia de soporte y mejoras en unidades de neonatología, en la actualidad el pronóstico con un adecuado tratamiento es alentador. Nos parece imperativo tener protocolos adecuados de toma de decisión en la embarazada con pancreatitis aguda, puesto que, a pesar de ser una patología de baja prevalencia, un correcto enfrentamiento puede mejorar el resultado materno-fetal. El presente trabajo propone una guía de manejo clínico interdisciplinario de la embarazada con pancreatitis y aporta una revisión actual sobre este tema.(AU)

Acute pancreatitis (PA) is a rare disease during pregnancy, with cholelithiasis being one of its major etiologies and Chile one of the countries with the highest prevalence of cholelithiasis in the world. This pathology has traditionally reported high rates of maternal- fetal mortality, as well as the risk of fetal morbidity. However, thanks to the advances in supportive therapy and improvements in neonatal units, the prognosis with an adequate treatment is now encouraging. It seems imperative to have adequate decision-making protocols in the pregnant woman with acute pancreatitis, since despite being a pathology of low prevalence a correct confrontation can improve the maternal-fetal outcome. This paper proposes an interdisciplinary clinical management guide for pregnant women with pancreatitis and provides a current review on this topic.(AU)

Prevalence and predictors of exclusive breastfeeding at hospital discharge.

OBJECTIVE: To estimate the population-based prevalence and predictors of exclusive breastfeeding at hospital discharge in singleton and twin term newborns. METHODS: We studied all hospital births in the province of Ontario, Canada, between April 1, 2009, and March 31, 2010, to perform a retrospective cohort study. We included live singleton and twin births, at term (37 0/7 weeks of gestation to 41 6/7 weeks of gestation), with information about feeding at maternal-newborn discharge. Descriptive statistics were performed and logistic regression was used to identify factors related to exclusive breastfeeding. RESULTS: Our study population consisted of 92,364 newborns, of whom 56,865 (61.6%) were exclusively breastfed at discharge. Older, nonsmoking, higher-income mothers with no pregnancy complications or reproductive assistance were more likely to breastfeed. Mothers of twins were less likely to exclusively breastfeed (adjusted odds ratio [OR] 0.30, 95% confidence interval [CI] 0.25-0.36) as were women who did not attend prenatal classes (adjusted OR 0.80, 95% CI 0.76-0.83). Compared with patients of obstetricians (57%), women cared for by midwives (87%, adjusted OR 4.49, 95% CI 4.16-4.85) and family physicians (67%, adjusted OR 1.54, 95% CI 1.47-1.61) were more likely to exclusively breastfeed. Breastfeeding after a planned (50%, adjusted OR 0.56, 95% CI 0.52-0.60) or unplanned (48%, adjusted OR 0.48, 95% CI 0.44-0.51) cesarean delivery was less common than after a spontaneous vaginal birth (68%). Neonates born at 39, 38, and 37 weeks of gestation (compared with 41 weeks of gestation) were increasingly less likely to breastfeed (adjusted ORs 0.93, 95% CI 0.89-0.98; 0.84, 95% CI 0.80-0.88; and 0.71, 95% CI 0.67-0.76). CONCLUSION: This large population-based study found that fewer than two thirds of term newborns are exclusively breastfed at hospital discharge, substantially lower than previously reported. LEVEL OF EVIDENCE: II.

Specific instructions for estimating unclearly reported blinding status in randomized trials were reliable and valid.

OBJECTIVE: To test the reliability and validity of specific instructions to classify blinding, when unclearly reported in randomized trials, as "probably done" or "probably not done." STUDY DESIGN AND SETTING: We assessed blinding of patients, health care providers, data collectors, outcome adjudicators, and data analysts in 233 randomized trials in duplicate and independently using detailed instructions. The response options were "definitely yes," "probably yes," "probably no," and "definitely no." We contacted authors for data verification (46% response). For each of the five questions, we assessed reliability by calculating the agreement between the two reviewers and validity by calculating the agreement between reviewers' consensus and verified data. RESULTS: The percentage with unclear blinding status varied between 48.5% (patients) and 84.1% (data analysts). Reliability was moderate for blinding of outcome adjudicators (κ=0.52) and data analysts (κ=0.42) and substantial for blinding of patients (κ=0.71), providers (κ=0.68), and data collectors (κ=0.65). The raw agreement between the consensus record and the author-verified record varied from 84.1% (blinding of data analysts) to 100% (blinding of health care providers). CONCLUSION: With the possible exception of blinding of data analysts, use of "probably yes" and "probably no" instead of "unclear" may enhance the assessment of blinding in trials.

Potential impact on estimated treatment effects of information lost to follow-up in randomised controlled trials (LOST-IT): systematic review.

OBJECTIVE: To assess the reporting, extent, and handling of loss to follow-up and its potential impact on the estimates of the effect of treatment in randomised controlled trials. DESIGN: Systematic review. We calculated the percentage of trials for which the relative risk would no longer be significant under a number of assumptions about the outcomes of participants lost to follow-up. DATA SOURCES: Medline search of five top general medical journals, 2005-07. ELIGIBILITY CRITERIA: Randomised controlled trials that reported a significant binary primary patient important outcome. RESULTS: Of the 235 eligible reports identified, 31 (13%) did not report whether or not loss to follow-up occurred. In reports that did give the relevant information, the median percentage of participants lost to follow-up was 6% (interquartile range 2-14%). The method by which loss to follow-up was handled was unclear in 37 studies (19%); the most commonly used method was survival analysis (66, 35%). When we varied assumptions about loss to follow-up, results of 19% of trials were no longer significant if we assumed no participants lost to follow-up had the event of interest, 17% if we assumed that all participants lost to follow-up had the event, and 58% if we assumed a worst case scenario (all participants lost to follow-up in the treatment group and none of those in the control group had the event). Under more plausible assumptions, in which the incidence of events in those lost to follow-up relative to those followed-up is higher in the intervention than control group, results of 0% to 33% trials were no longer significant. CONCLUSION: Plausible assumptions regarding outcomes of patients lost to follow-up could change the interpretation of results of randomised controlled trials published in top medical journals.