El embarazo gemelar monocorial desde la perspectiva de la teoría de la complejidad / Monochorionic twin pregnancy from the perspective of the theory of complexity

En la práctica, es muy frecuente asociar las gestaciones gemelares monocoriales (MC) con embarazos complejos o complicados, utilizando ambos términos en forma intercambiable. Sin embargo, no lo son; el dinamismo es protagonista en los sistemas complejos, pero no en los complicados. Para entender a la embarazada con una gestación MC como un sistema complejo, primero se desarrollarán las características principales de los embarazos MC; su placenta es una de las principales responsables de los problemas. Luego se analizará el embarazo MC desde la complejidad, identificando las características del sistema y sus complicaciones como propiedades emergentes.

In practice, it is very common to associate monochorionic (MC) twin pregnancies with complex or complicated pregnancies, using both terms interchangeably. However, these are not synonyms; dynamism is the protagonist in complex systems, but not in complicated ones. In order to understand a MC pregnancy as a complex system, it is necessary to first look into its main characteristics. The placenta is one of the main sources of problems. Then, the MC pregnancy has to be analyzed from the perspective of complexity, identifying the system characteristics and its complications as emergent properties.

Fetal aortic valvuloplasty as the first step in a complex therapeutic strategy.

BACKGROUND: Fetal aortic valvuloplasty (FAV) is proposed to prevent hypoplastic left heart syndrome due to fetal critical aortic stenosis. OBJECTIVE: to report our experience on FAV as the first step in a complex therapeutic strategy. METHOD: Series of patients with FAV over an 18-year period. RESULTS: 27 FAVs were performed in 26 fetuses, with technical success in 82% (22/27) and periprocedural fetal demise in 22% (6/27), decreasing to 15% in the second half-cohort. Loss to follow-up was due to birth or postnatal therapy in other centers (5) and termination of pregnancy (1), A normal-sized LV at birth was observed in 46% (6/13), 4 neonates underwent aortic valvuloplasty and 2 cardiac surgeries, with 5/6 achieving biventricular circulation at 28 days, and 3 transplant-free survival at mid-term follow-up. The 7/13 born with a borderline LV underwent LV rehabilitation strategy, with survival at 28 days in 4/7 and at mid-term in 3: one with biventricular circulation, one with a ventricle-and-a-half repair, and one lost to follow-up. CONCLUSION: FAV was feasible in most cases, with no maternal complications, and biventricular circulation at 28 days in ∼40% of survivors. After FAV, a diverse range of postnatal cardiac interventions are performed, reflecting the challenging innovation in current cardiovascular therapy.

Monochorionic twin pregnancy from the perspective of the theory of complexity. / El embarazo gemelar monocorial desde la perspectiva de la teoría de la complejidad.

In practice, it is very common to associate monochorionic (MC) twin pregnancies with complex or complicated pregnancies, using both terms interchangeably. However, these are not synonyms; dynamism is the protagonist in complex systems, but not in complicated ones. In order to understand a MC pregnancy as a complex system, it is necessary to first look into its main characteristics. The placenta is one of the main sources of problems. Then, the MC pregnancy has to be analyzed from the perspective of complexity, identifying the system characteristics and its complications as emergent properties.

En la práctica, es muy frecuente asociar las gestaciones gemelares monocoriales (MC) con embarazos complejos o complicados, utilizando ambos términos en forma intercambiable. Sin embargo, no lo son; el dinamismo es protagonista en los sistemas complejos, pero no en los complicados. Para entender a la embarazada con una gestación MC como un sistema complejo, primero se desarrollarán las características principales de los embarazos MC; su placenta es una de las principales responsables de los problemas. Luego se analizará el embarazo MC desde la complejidad, identificando las características del sistema y sus complicaciones como propiedades emergentes.

Performance of the cervical shortening for prediction of spontaneous preterm birth in uncomplicated twins.

OBJECTIVE: There is a lack of consensus about the management of twins with significant cervical length (CL) shortening, especially if CL is above 25 mm. Therefore, it is important to define "abnormal" CL change over time, and to compare the performance of different strategies. The aim of this study was twofold, to describe the performance of the cervical shortening and that of an integrated strategy that includes both the cervical shortening and a fixed CL cutoff <25 mm in any measurement as predictor of spontaneous PTB (sPTB) < 34 weeks in uncomplicated twin pregnancies. MATERIAL AND METHODS: Retrospective cohort study of twins followed in our Twins Clinic at Hospital Italiano de Buenos Aires from 2013 to 2017. Inclusion criteria were dichorionic or monochorionic diamniotic twins with CL measurement between 18 and 33 + 6 weeks with available data of the delivery. Exclusion criteria included any of the following complications: iatrogenic preterm delivery <34 weeks, cerclage, fetal growth restriction, fetal death, structural anomalies, polyhydramnios, twin-twin transfusion syndrome, selective fetal growth restriction, twin anemia-polycythemia sequence, and twin reversed arterial perfusion sequence. Spontaneous preterm birth was defined as spontaneous delivery <34 weeks. Cervical shortening was analyzed in the following periods: 20-24 weeks, 20-28 weeks, 24-28 weeks, 24-32 weeks and 28-32 weeks. Cervical changes were analyzed as velocity of shortening over time (mm/week) and as the ratio of shortening over time (%/week). ROC curves for each period were constructed and two different cutoffs were used to classify changes of the CL as positive or negative screening: a) the shortening of CL associated to the highest value of the Youden Index and b) fixing a 10% false positive rate (FPR). For the second objective, we analyzed an integrated strategy considering a fixed cutoff of 25 mm at any GA and/or a significant shortening. The screening was considered positive if any CL measurement was <25 mm at any GA or there was a shortening of the CL ≥ the cutoff obtained for each period. We report sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio and area under the ROC curve. RESULTS: We included 378 patients and 1417 measurements, 284 (75%) dichorionic and 94 (25%) monochorionic. Between 20 and 28 weeks, with a change in CL cutoff = 1.6 mm/week or 4.1%/week the detection rate was 54.2% (32.8-74.4%) and the specificity 80.5% (75.1-85.1%) and 83.5% (78.5-87.8%) respectively. In the integrated strategy, the detection rate was 65.7% (47.8-80.9%) and the specificity 69 (63.7-74). All the ROC curves of the periods studied showed an AUC < 0.7. In the group of patients that delivered preterm the initial mean CL was shorter than in the term group, 39 (±12) mm vs. 43 (± 7.7) mm (p = .02) and the most important change in CL was at 20-24 weeks both in the velocity and in the ratio of shortening over time. Conversely, patients that delivered at term showed a higher change in CL in the third trimester. CONCLUSION: The performance of all the strategies analyzed as a predictor of sPTB <34 weeks was moderate. The period 20-28 weeks detected half of the patients at risk with a FPR around 10-20% and the integrated strategy increased the sensitivity up to a detection of two thirds of the patients at risk but with a FPR of ∼30%. Future analyses need to explore other strategies to improve the performance and to really identify the patients at higher risk.

Cervical-length as a screening for spontaneous preterm birth in uncomplicated twins: one vs. serial measurements.

OBJECTIVE: While cervical length (CL) provides an effective screening tool for spontaneous preterm birth in singletons, the performance in twins is still controversial. Our aim was twofold. First, to compare the performance of a single CL measurement at mid-gestation (∼20 weeks) versus serial measurements as a predictor of spontaneous preterm birth < 34 weeks in uncomplicated twin pregnancies. Second, to describe the performance of a single CL at ∼24, ∼28 and ∼32 weeks. MATERIAL AND METHODS: cohort study of twins followed at Hospital Italiano de Buenos Aires from 2013 to 2017. Inclusion criteria were dichorionic or monochorionic diamniotic twins with CL measurement between 18 and 33 + 6 weeks with available data of the delivery. Exclusion criteria included any of the following complications: iatrogenic preterm delivery <34 weeks, cerclage, fetal growth restriction, fetal death, structural anomalies, polyhydramnios, twin-twin transfusion syndrome, selective fetal growth restriction, twin anemia-polycythemia sequence, and twin reversed arterial perfusion sequence. Spontaneous preterm birth was defined as spontaneous delivery < 34 weeks. Two different cutoffs were used to classify CL as short (positive screening) or normal (negative screening): (a) a fixed cutoff of 25 mm at any gestational age (GA). The screening was considered positive if any CL measurement was <25 mm; and (b) a GA adjusted cutoff to a 10% false positive rate (FPR). The 10% FPR for each GA was calculated and the screening was considered positive if any of the CL measurements were below this 10% FPR cutoff. We report sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio and area under the ROC curve. RESULTS: Among 777 twins followed in our Unit, 381 met exclusion criteria and 18 were excluded due to incomplete follow-up. We included 378 patients, 284 (75%) dichorionic and 94 (25%) monochorionic. The performance of one CL at 20 weeks showed a sensitivity ≤ 20% with an area under the ROC curve of 0.58 (95% CI, 0.45-0.70), while the performance of serial measurements showed a sensitivity of 58.8% (95% CI, 40.7-75.4) with an area under the ROC curve of 0.70 (95% CI, 0.61-0.79) (p < .001). The analyses of the performance of a single CL at ∼24, ∼28 and ∼32 weeks showed similar AUC than the serial measurements and, for a FPR = 10%, the performance of one measurement at 24 and 32 weeks showed a sensitivity of 30% (95% CI, 14.7-49.4) and 31.6% (95% CI, (12.6-56.6), while the measurement at 28 weeks showed a sensitivity of 48.3% (95% CI, (29.4-67.5). CONCLUSION: Serial measurements showed a better performance than a single one in mid-gestation. Moreover, among single measurements the CL in mid-gestation showed the poorest performance, while the 28 weeks assessment detected half of the preterm deliveries. However, all the strategies showed modest performances.

Actualización del diagnóstico prenatal y cirugía fetal del mielomeningocele / Update on prenatal diagnosis and fetal surgery for myelomeningocele

A partir del estudio seminal Management of Myelomeningocele Study en el año 2011, el cual demostró que la reparación prenatal del defecto del mielomeningocele antes de la semana 26 mejoraba los resultados neurológicos, la cirugía fetal fue incorporada dentro de las opciones de estándar de cuidado. Así, el diagnóstico prenatal del mielomeningocele dentro de la ventana terapéutica se convirtió en un objetivo obligatorio y, por ello, se intensificó la investigación de estrategias de tamizaje, sobre todo, en el primer trimestre. Además, se desarrollaron distintas técnicas de cirugía fetal para mejorar los resultados neurológicos y disminuir los riesgos maternos. El objetivo de la siguiente revisión es actualizar los avances en tamizaje y diagnóstico prenatal en el primer y segundo trimestre, y en cirugía fetal abierta y fetoscópica del mielomeningocel

A seminal study titled Management of Myelomeningocele Study, from 2011, demonstrated that prenatal myelomeningocele defect repaired before 26 weeks of gestation improved neurological outcomes; based on this study, fetal surgery was introduced as a standard of care alternative. Thus, prenatal myelomeningocele diagnosis within the therapeutic window became a mandatory goal; therefore, research efforts on screening strategies were intensified, especially in the first trimester. In addition, different fetal surgery techniques were developed to improve neurological outcomes and reduce maternal risks. The objective of this review is to provide an update on the advances in prenatal screening and diagnosis during the first and second trimesters, and in open and fetoscopic fetal surgery for myelomeningocele

Update on prenatal diagnosis and fetal surgery for myelomeningocele. / Actualización del diagnóstico prenatal y cirugía fetal del mielomeningocele.

A seminal study titled Management of Myelomeningocele Study, from 2011, demonstrated that prenatal myelomeningocele defect repaired before 26 weeks of gestation improved neurological outcomes; based on this study, fetal surgery was introduced as a standard of care alternative. Thus, prenatal myelomeningocele diagnosis within the therapeutic window became a mandatory goal; therefore, research efforts on screening strategies were intensified, especially in the first trimester. In addition, different fetal surgery techniques were developed to improve neurological outcomes and reduce maternal risks. The objective of this review is to provide an update on the advances in prenatal screening and diagnosis during the first and second trimesters, and in open and fetoscopic fetal surgery for myelomeningocele.

A partir del estudio seminal Management of Myelomeningocele Study en el año 2011, el cual demostró que la reparación prenatal del defecto del mielomeningocele antes de la semana 26 mejoraba los resultados neurológicos, la cirugía fetal fue incorporada dentro de las opciones de estándar de cuidado. Así, el diagnóstico prenatal del mielomeningocele dentro de la ventana terapéutica se convirtió en un objetivo obligatorio y, por ello, se intensificó la investigación de estrategias de tamizaje, sobre todo, en el primer trimestre. Además, se desarrollaron distintas técnicas de cirugía fetal para mejorar los resultados neurológicos y disminuir los riesgos maternos. El objetivo de la siguiente revisión es actualizar los avances en tamizaje y diagnóstico prenatal en el primer y segundo trimestre, y en cirugía fetal abierta y fetoscópica del mielomeningocele.

Cardiopatías congénitas, diagnóstico y manejo prenatal / Congenital heart disease, prenatal diagnosis and management

Dentro de las malformaciones congénitas, las cardiopatías son las anomalías más frecuentes y se asocian a una elevada morbimortalidad perinatal y a largo plazo. El objetivo de esta actualización es revisar la tasa de detección prenatal, las características del tamizaje a lo largo del embarazo, tanto en el primero como en el segundo trimestre, las indicaciones de ecocardiografía avanzada, y establecer un algoritmo de manejo ante el diagnóstico prenatal de una cardiopatía congénita. Se discutirán los estudios invasivos y no invasivos que pueden realizarse y el seguimiento obstétrico. Finalmente, se revisarán las características principales de la terapia fetal en anomalías cardíacas, tanto intervencionismo cardíaco como el tratamiento intrauterino de las arritmias.

Among congenital malformations, heart defects are the most common type of anomaly, and these are associated with a high perinatal, long-term morbidity and mortality. The objective of this update was to review the rate of prenatal detection, screening characteristics throughout the pregnancy, in both the first and second trimesters, indications for advanced echocardiography, and to establish a management algorithm in case of prenatal diagnosis of a congenital heart disease. Potential invasive and non-invasive tests and obstetric follow-up will be discussed here. Finally, the main characteristics of fetal therapy in heart anomalies will be reviewed, both cardiac interventions and intrauterine treatment of arrhythmias.

Congenital heart disease, prenatal diagnosis and management. / Cardiopatías congénitas, diagnóstico y manejo prenatal.

Among congenital malformations, heart defects are the most common type of anomaly, and these are associated with a high perinatal, longterm morbidity and mortality. The objective of this update was to review the rate of prenatal detection, screening characteristics throughout the pregnancy, in both the first and second trimesters, indications for advanced echocardiography, and to establish a management algorithm in case of prenatal diagnosis of a congenital heart disease. Potential invasive and non-invasive tests and obstetric follow-up will be discussed here. Finally, the main characteristics of fetal therapy in heart anomalies will be reviewed, both cardiac interventions and intrauterine treatment of arrhythmias.

Dentro de las malformaciones congénitas, las cardiopatías son las anomalías más frecuentes y se asocian a una elevada morbimortalidad perinatal y a largo plazo. El objetivo de esta actualización es revisar la tasa de detección prenatal, las características del tamizaje a lo largo del embarazo, tanto en el primero como en el segundo trimestre, las indicaciones de ecocardiografía avanzada, y establecer un algoritmo de manejo ante el diagnóstico prenatal de una cardiopatía congénita. Se discutirán los estudios invasivos y no invasivos que pueden realizarse y el seguimiento obstétrico. Finalmente, se revisarán las características principales de la terapia fetal en anomalías cardíacas, tanto intervencionismo cardíaco como el tratamiento intrauterino de las arritmias.

Bisfenol-A: cuantificacion en orina de mujeres embarazadas por cromatografia gaseosa-espectrometria de masa / Bisfenol-A: quantification in urine of pregnant women by gas chromatography-mass spectrometry / Bisfenol-A: quantificacao em urina de gestantes por cromatografia gasosa-espectrometria de massa

El uso de bisfenol-A (BPA) a nivel de la industria global se ha venido incrementando en los ultimos anos, y fueron los mercados emergentes los impulsores de esta demanda creciente. Las aplicaciones de BPA en la industria de los alimentos y bebidas representan solo del 3 al 4% del consumo global de policarbonato, pero su uso esta siendo reexaminado debido a que se conocieron varios trabajos cientificos que indican la existencia de una relacion directa entre el BPA y los efectos adversos para la salud. La contaminacion de los alimentos y bebidas se produce por migracion del BPA desde los envases que los contienen (alimentos enlatados, vinos, etc.), y es la principal fuente de exposicion en el humano. Para evaluar dicha exposicion se desarrollo y valido un metodo analitico por cromatografia gaseosa acoplada a espectrometria de masa para la cuantificacion de BPA total en orina de mujeres embarazadas atendidas en el Hospital Italiano de Buenos Aires en el ano 2013, con un limite de cuantificacion de 2,0 ng/mL y un limite de deteccion de 0,8 ng/mL. De las 149 muestras de orina analizadas, el 66,4% fueron cuantificables, con la mediana de BPA total de 4,8 ng/mL (4,3 ng/mg de creatinina) y la media geometrica de 4,8 ng/mL (4,7 ng/mg de creatinina).

The use of bisphenol-A (BPA) at the level of the global industry has been increasing in recent years, with emerging markets being the drivers of this growing demand. BPA applications in the food and beverage industry represent only 3 to 4% of the global consumption of polycarbonate, but its use is being reexamined because several scientific works were reported indicating the existence of a direct relationship between BPA and adverse effects on health. The contamination of food and beverages is produced by the migration of BPA from the containers that hold them (canned foods, wines, etc.) and it is the main source of exposure in humans. To evaluate this exposure, an analytical method was developed by gas chromatography coupled to mass spectrometry for the quantification of total BPA in urine of pregnant women treated at the Hospital Italiano de Buenos Aires in 2013, with a limit of quantification of 2.0 ng/mL and of detection of 0.8 ng/mL. Of the 149 urine samples analyzed, 66.4% were quantifiable, with a median total BPA of 4.8 ng/mL (4.3 ng/mg creatinine) and a geometric mean of 4.8 ng/mL (4.7 ng/mg creatinine).

O uso de bisfenol-A (BPA) ao nivel da industria global foi aumentando nos ultimos anos, e foram os mercados emergentes que deram impulso a essa demanda crescente. As aplicacoes de BPA na industria de alimentos e bebidas representam apenas 3 a 4% do consumo global de policarbonato, mas seu uso esta sendo reexaminado visto que varios trabalhos cientificos indicando a existencia de uma relacao direta entre o BPA e os efeitos adversos na saude foram conhecidos. A contaminacao dos alimentos e bebidas e produzida pela migracao de BPA das embalagens que os contem (alimentos enlatados, vinhos, etc.) e e a principal fonte de exposicao em humanos. Para avaliar esta exposicao, foi desenvolvido e avaliado um metodo analitico por cromatografia gasosa acoplada a espectrometria de massas para a quantificacao do BPA total na urina de gestantes atendidas no Hospital Italiano de Buenos Aires em 2013, com um limite de quantificacao de 2,0 ng/mL e um limite de deteccao de 0,8 ng/mL. Das 149 amostras de urina analisadas, 66,4% foram quantificaveis, com uma mediana de BPA total de 4,8 ng/mL (4,3 ng/mg de creatinina) e a media geometrica de 4,8 ng/mL (4,7 ng/mg de creatinina).

Fetal exposure to bisphenol A: Presence of bisphenol A in urine of pregnant women assisted in a hospital in the City of Buenos Aires. Year 2013. / [Exposición fetal a bisfenol A: Presencia de bisfenol A en orina de mujeres gestantes asistidas en un hospital de la Ciudad de Buenos Aires. Año 2013.]

Introduction: Bisphenol A (BPA) is an endocrine disruptor (ED) possibly linked to adverse reproductive and neurodevelopmental effects that is used as an additive in food and beverage containers. There are no data of BPA levels in the Argentine population. The objective of this study was to measure BPA in the urine of pregnant women. Methods: Cross-sectional study. Detection of BPA in pregnant women of the Hospital Italiano de Buenos Aires in 2013, using gas chromatography and mass spectrometry with a limit of quantification of 2 ng / ml and detection of 0.8 ng / ml. The proportion of women exposed to BPA within the 95% confidence interval (IC 95%) is described. Results: 149 pregnant women, average age 32 years (Standard Deviation 5.3), 81% (95% CI 73.9-86.9) workers and 83.7% (95% CI 76.7-89.1) have university or higher education, 66.4% (95% CI 58-74.0) of the urinary samples were quantifiable, with a median BPA of 4.3 ng/mg Cr (RI 3.2-6.7). Conclusions: This study shows that exposure to BPA during the process of embryonic development in a sector of the population of Argentina is widespread. In Argentina, the use of this ED is only regulated in baby bottles.

Introducción: El Bisfenol A (BPA) es un disruptor endócrino (DE) posiblemente vinculado a eventos adversos reproductivos y del desarrollo neurológico que se utiliza como aditivo en envases plásticos de alimentos y bebidas. En la población argentina no existen datos sobre niveles de BPA en orina. El objetivo del estudio fue medir la presencia de BPA en orina de embarazadas. Métodos: Estudio transversal. Detección de BPA en orina de embarazadas atendidas en el Hospital Italiano de Buenos Aires en el año 2013. La técnica utilizada fue cromatografía gaseosa asociada a espectrometría de masa con un límite de cuantificación de 2 ng/ml y de detección de 0,8 ng/ml. Se describe la proporción de mujeres con exposición al BPA con su intervalo de confianza del 95% (IC95%). Resultados: se analizaron 149 muestras de orina de embarazadas de edad promedio 32 años (Desvío Standard 5,3), el 81% (IC95% 73,9-86,9) trabaja y el 83,7% (IC95% 76,7-89,1) posee nivel universitario y/o posgrado.El 66,4% (IC95% 58,2-74,0) de las muestras urinarias presentaron BPA cuantificable, siendo la mediana de BPA de 4,3 ng / mg creatinina (Rango Intercuartilo 3,2-6,7). Conclusiones: Este estudio muestra que la exposición a BPA durante el proceso de formación embrionaria en un sector de la población de Argentina, es generalizada. En Argentina solo está regulado el uso de este DE en mamaderas.

Non-conservative Management of Placenta Accreta Spectrum in the Hybrid Operating Room: A Retrospective Cohort Study.

INTRODUCTION: Hysterectomy is the standard of care in placenta accreta spectrum (PAS). To reduce the risks of obstetric hemorrhage during surgery, endovascular interventions have been proposed. Our aim is to evaluate the feasibility and safety of the overall non-conservative management of PAS in the hybrid operating room (OR) to replace the classic two-step procedure (catheterization in the interventional radiology suite and transfer to conventional OR). MATERIALS AND METHODS: This is a retrospective study of series of patients with histopathologic confirmation of PAS treated in the hybrid OR at the same university hospital. We used for comparison our historical cohort managed with the standard two-step procedure. RESULTS: We included 110 patients, 80 in the conventional OR and 30 in the hybrid OR. There were no cases of major complications attributable to the endovascular procedures. In the two-step procedure, there were 10 (12.5%) intra-arterial catheter displacements that required repositioning in the conventional OR under mobile C-arm fluoroscopy and no cases in the hybrid OR (p = 0.04). The mean operative time was 380 + 42 min in the conventional OR and 296 + 66 min in the hybrid OR (p = .00001). There were no differences in the gestational age at delivery, postoperative length of stay, or large-volume blood transfusion. There were no maternal deaths. CONCLUSIONS: The overall non-conservative management of PAS in the hybrid OR has shown to be feasible and safe in our series, offering potential advantages to replace the classic two-step procedure. More studies are needed to evaluate whether this strategy is cost-effective and whether it may improve maternal and perinatal outcomes.

Preterm premature rupture of membranes. / Ruptura prematura de membranas en nacimientos de pretérmino.

Preterm premature rupture of membranes occurs in around 3% of pregnancies, and several aspects related to its management are still controversial. The objective of this update is to provide a detailed review of strategies aimed at reducing morbidity and mortality associated with this maternal condition. We will discuss the available evidence regarding the maternal use of antibiotics, the use of corticosteroids according to gestational age, the use of magnesium sulphate for fetal neuroprotection, the use of tocolytic agents, and the best moment for and route of delivery. This review also covers the effects of prolonged preterm premature rupture of membranes, infant morbidity and mortality in the short and long term, the harmful effects of antibiotics after delivery, including the effects on neurodevelopment and the presence of longterm chronic diseases.

La ruptura prematura de membranas de pretérmino ocurre en, aproximadamente, el 3% de los embarazos y numerosos aspectos vinculados a su manejo continúan siendo controversiales. El objetivo de esta actualización es revisar en forma detallada las estrategias destinadas a disminuir la morbilidad y mortalidad asociadas a esta situación clínica en las madres. Se discutirá la evidencia disponible acerca del uso en las madres de antibióticos, corticoides a distintas edades gestacionales, sulfato de magnesio como neuroprotector fetal, tocolíticos y el momento óptimo y la vía de finalización del embarazo. Asimismo, se incluyen los efectos de la ruptura prolongada de membranas en prematuros, la mortalidad y morbilidad de los recién nacidos en el corto y largo plazo, los perjuicios de la administración de antibióticos luego del nacimiento con las secuelas en el neurodesarrollo y la presencia de enfermedades crónicas a largo plazo.

Cuantificación de Bisfenol-A libre en sangre de cordón umbilical humano a nivel de trazas / Quantification of free Bisphenol-A in human umbilical cord blood at trace level / Quantificação de Bisfenol-A livre em sangue de cordão umbilical humano a nível de traços

El Bisfenol-A (BPA) es ampliamente utilizado en la producción de plásticos de policarbonato, por lo que está presente en productos de uso masivo. Es un disruptor endócrino e incide en el desarrollo gonadal y del sistema nervioso central. La exposición de mujeres embarazadas al BPA es particularmente preocupante para el feto en desarrollo, debido a que atraviesa la placenta pasando a la sangre de cordón y al líquido amniótico. Esto se suma a la escasa o nula actividad enzimática fetal para biotransformarlo en BPA-glucurónido inactivo, causando posibles efectos nocivos a la descendencia a dosis muy bajas y sostenidas. Con el propósito de estudiar la exposición al BPA y sus efectos en la población de Argentina se desarrolló y validó un método analítico por cromatografía líquida acoplada a espectrometría de masa, que permite la cuantificación de trazas de BPA libre (forma estrogénica, activa) en plasma de cordón umbilical. La técnica consiste en la precipitación de proteínas de la sangre de cordón por agregado de acetonitrilo y posterior centrifugado e inyección del sobrenadante. Se utilizó una elución isocrática en la cromatografía líquida, y la espectrometría de masa se realizó empleando Electrospray negativo en modo de monitoreo de reacciones múltiples. Los valores de BPA libre cuantificados están en el rango de 1,0 a 12,1 ng/mL, límite de detección: 0,6 ng/mL.

Bisphenol-A (BPA) is widely used in the production of polycarbonate plastics and therefore, it is present in products of massive use. It is known as an endocrine disruptor and has an impact on gonadal and central nervous system development. Exposure of pregnant women to BPA is particularly worrying for the developing fetus because it crosses the placenta into the cord blood and amniotic fluid, coupled with little or no fetal enzymatic activity to biotransform it into inactive BPA-glucuronide, causing possible harmful effects to the offspring at very low and sustained doses. With the aim to study the exposure to BPA and its effects on the population of Argentina, an analytical method was developed and validated by liquid chromatography coupled to mass spectrometry, which allows the quantification of trace amounts of free BPA (estrogenic, active form) in plasma of umbilical cord. The method involves protein precipitation by the addition of acetonitrile and subsequent centrifugation and injection of supernatant. An isocratic elution was used in liquid chromatography, and mass spectrometry was performed using negative Electrospray mode in multiple reaction monitoring. Quantified free BPA values are in the range of 1.0 to 12.1 ng/mL, Detection Limit: 0,6 ng/mL.

O Bisfenol-A (BPA) é amplamente utilizado na produção de plásticos de policarbonato, portanto está presente em produtos de uso massiço. Ele é um disruptor endócrino e tem um impacto no desenvolvimento gonadal e do sistema nervoso central. A exposição de mulheres grávidas ao BPA é particularmente preocupante para o feto em desenvolvimento, visto que atravessa a placenta passando ao sangue do cordão e ao líquido amniótico Isso é adicionado à pouca ou nula atividade enzimática fetal para biotransformá-lo em BPA-glicuronídeo inativo, o que causa possíveis efeitos nocivos aos descendentes em doses muito baixas e sustentadas. Visando a estudar a exposição ao BPA e seus efeitos na população da Argentina, foi desenvolvido e validado um método analítico por cromatografia líquida acoplada à espectrometria de massa, que permitem a quantificação de vestígios de BPA livre (forma estrogênica, livre) em plasma do cordão umbilical. A técnica consiste na precipitação de proteínas do sangue de cordão por adição de acetonitrila e posterior centrifugação e injeção no sobrenadante. Na cromatografia líquida, foi utilizada uma eluição isocrática, e a espectrometria de massa foi realizada utilizando Electrospray negativo em modo de monitoramento de reações múltiplas. Os valores de BPA livre quantificados estão na faixa de 1,0 a 12,1 ng/mL, limite de detecção: 0,6 ng/mL.

Sonographic detection of open spina bifida in the first trimester: review of the literature.

In the beginnings, sonographic diagnosis of open spina bifida (OSB) relied on the meticulous scanning of the fetal vertebrae for abnormalities but many defects were missed. After the mid-1980s, however, with the description of the intracranial findings in the second trimester (the "lemon sign" and the "banana sign"), the prenatal diagnosis of OSB was enhanced. In the last 2 decades, there has been widespread uptake of routine ultrasound examination in the first trimester of pregnancy with the purpose of the measurement of fetal crown-rump length to determine gestational age, to screen for trisomy 21 and other aneuploidies, mainly with the nuchal translucency, and for diagnosis of many major abnormalities. Many papers were published focusing on early diagnosis of myelomeningocele (MMC), and the objective of this review is to summarize the different techniques described regarding prenatal diagnosis of OSB in the first trimester of pregnancy.

Discordance of cord insertions as a predictor of discordant fetal growth in monochorionic twins.

INTRODUCTION: The type of cord insertion within monochorionic twin pairs could be different. The purpose of study is to evaluate the association of different combinations of placental umbilical cord insertions with birth weight discordance in a large cohort of monochorionic twins. METHODS: All consecutive monochorionic placentas from either uncomplicated twin pregnancies or with fetal weight discordance examined and injected with color dye at our centers were included in this study (n = 374). Marginal or velamentous cord insertions were defined as abnormal. Placentas were categorized as concordant when the cord insertions of both fetuses were either normal-normal or abnormal-abnormal, and as discordant when they were normal-abnormal. Birth weight discordance was defined as a difference in birth weight of each twin ≥25%. The association of different cord insertion combinations with birth weight discordance was analyzed. RESULTS: The rate of discordant cord insertions was 55% (204/374) in monochorionic twins. A highly significant association between discordant cord insertions and discordant birth weight was observed (p < 0.01). The odds ratios (OR) for birth weight discordance in the discordant cord insertion group compared with the concordant group were 2.3 (95% CI: 1.2-4.4) for the normal-marginal and 5.9 (95% CI: 3.8-10.4) for the normal-velamentous cord insertion subgroup. Discordant cord insertions are associated with the occurrence of unequal placental sharing (OR 4.3, 95%CI 2.7-6.9). DISCUSSION: Discordance of cord insertions is associated with discordance of birth weight and may therefore be an important indicator of adverse outcome in monochorionic twins.

Stomach in Contact with the Bladder: A Sonographic Sign of Left Congenital Diaphragmatic Hernia.

The evaluation of the characteristics of the fetal stomach should be part of every routine prenatal ultrasound after 11 weeks. A position that has not been previously described in the literature is the stomach in contact with the bladder. We describe 6 cases with the ultrasonographic finding of the stomach in contact with the bladder, all of them in fetuses with left-sided congenital diaphragmatic hernia. Even though the reasons for this striking position of the stomach are not clear, our series highlights the fact that the visualization of the stomach in contact with the bladder may be a specific sonographic marker of congenital diaphragmatic hernia.