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.

Prevention of preterm birth in twin-to-twin transfusion syndrome: a systematic review and network meta-analysis.

OBJECTIVES: We aimed to perform a systematic review and network meta-analysis to evaluate the preventive strategies for preterm birth in twin-to-twin transfusion syndrome. METHODS: PubMed, Embase and Cochrane Central were searched from inception to December 2023 with no filters. Additionally, the reference lists of the included studies were manually examined to identify any supplementary studies. We selected randomized controlled trials and cohorts comparing interventions to prevent preterm birth in twin pregnancies complicated by twin-to-twin transfusion syndrome. A random-effects frequentist network meta-analysis was performed using RStudio version 4.3.1. Randomized controlled trials and cohorts were assessed respectively using the Risk of Bias in Non-randomized Studies of interventions tool and Cochrane Collaboration's tool for assessing risk of bias in randomized trials. RESULTS: In this systematic review and meta-analysis, we included eight studies comprising a total of 719 patients. Compared with expectant management, cerclage stood out as the only intervention associated with an increase in the survival of at least one twin (risk ratio 1.12; 95 % confidence interval 1.01-1.23). Our subgroup analysis based on different thresholds for short cervix demonstrated a significant reduction in the risk of preterm birth before 32 weeks with ultrasound-indicated cerclage using a 15 mm criterion (risk ratio 0.65; 95 % confidence interval 0.47-0.92). CONCLUSIONS: Our study suggests the potential benefit of cerclage as a preventive strategy for preterm birth in pregnancies complicated by twin-to-twin transfusion syndrome. These findings highlight the necessity for further investigation to corroborate our results and address the optimal threshold for ultrasound-indicated cerclage.

Heterotopic twin pregnancy in unicornuate uterus and non-communicating rudimentary horn with survival of both fetuses: Magnetic resonance imaging and 3D reconstructions findings.

We reported a case of heterotopic twin pregnancy in a unicornuate uterus with a non-communicating rudimentary horn with survival of both fetuses. The diagnosis was made late at 28 weeks of gestation, with suspicion raised by ultrasound and confirmed by magnetic resonance imaging (MRI). During hospitalization, obstetric ultrasound with color Doppler was performed every 2 days to assess fetal well-being and myometrial thickness, which was determined by measurements of the uterine wall at the accessory horn. Elective cesarean section was performed at 33 + 5 weeks of gestation. Delivery started with the fetus in the rudimentary horn, with subsequent extraction of the fetus in the unicornate uterus. Three-dimensional virtual reconstruction allowed a spatial view of the both uterus and fetuses with better understanding of the obstetrical condition by the parents and interactive discussion by the multidisciplinary medical team.

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.

Characteristics of the oral glucose tolerance test in women with different pre-pregnancy body mass index and the effect of gestational diabetes mellitus on twin pregnancy outcomes.

OBJECTIVE: This study aimed to investigate the mid-pregnancy blood glucose levels of women with singleton or twin pregnancies. METHOD: The relationship between blood glucose levels and Gestational Diabetes Mellitus (GDM) was studied in women with different pre-pregnancy Body Mass Index (BMI), and the effect of GDM on twin pregnancy outcomes was analyzed. Women with twin (n = 1,985) and singleton (n = 1,985) pregnancies were categorized into underweight (BMI < 18.5 kg/m2, n = 597), normal weight (BMI: 18.5-23.9 kg/m2, n = 2,575), and overweight/obese (BMI ≥ 24 kg/m2, n = 798) groups. RESULTS: The incidence of GDM was 21.01% in women with twin pregnancies. Among the women with GDM in twin pregnancies, 38.37% had at least two abnormal blood glucose levels. The incidence of these parameters increased with preconception BMI, and the incidence of twin pregnancies was higher than that of singleton pregnancies (p < 0.001). In the normal weight and overweight/obese group, the oral glucose tolerance test glucose level and incidence of GDM were higher in women with twin than singleton pregnancies (p < 0.05). For twin pregnancies, the prevalence of selective fetal growth restriction was higher and anemia was lower in the GDM group than in the non-GDM group (all p < 0.05). CONCLUSION: Therefore, a greater emphasis should be placed on BMI before conception, and well-controlled GDM does not increase adverse pregnancy outcomes for twin pregnancies.

The Management of Acardiac Twinning: Twin Reverse Arterial Perfusion Sequence - An International Survey.

INTRODUCTION: The optimal approach and therapy method for the acardiac twin with a reverse arterial perfusion sequence has not yet been established. The aim of this study was to determine the clinical practice patterns among international fetal therapy units in their management of these cases. METHODS: A survey was sent to fetal centers across the world via email between December 2020 and December 2021. RESULTS: Responses were obtained from 77% contacted centers. The most frequent ultrasound variables used in the evaluation of twin reverse arterial perfusion sequence include echocardiographic assessment of the pump twin and umbilical artery Doppler waveforms in the acardiac and pump twins, in 90% and 80% of the centers, respectively. Most centers in Europe and Latin America propose an in utero intervention in all cases. Most centers in Europe and Latin America prefer interstitial laser ablation, whereas radiofrequency ablation (RFA) is preferred in North America. The earliest gestational age for an intervention is on mean 13 weeks in Europe, which is earlier than the other geographic areas (p = 0.001). CONCLUSIONS: Most centers agreed that antenatal evaluation should include echocardiography along with the UA Doppler waveform measurements, and the most frequently used interventions were interstitial laser ablation or RFA at a median between 14 and 26 weeks.

Síndrome HELLP y rotura hepática en un embarazo gemelar: presentación de un caso / HeLLP Syndrome and Hepatic Rupture in a Twin Pregnancy: A Case Report / Síndrome HeLLP e ruptura hepática em gestação gemelar: relato de caso

Introducción: el síndrome HELLP y rotura hepática es una complicación poco frecuente, especialmente en casos de embarazo gemelar. Se presenta el caso de un hematoma subcapsular hepático roto por síndrome HELLP que complicó un embarazo gemelar que requirió una cesárea de emergencia y para el manejo de la hipovolemia, el empaquetamiento hepático. Presentación del caso: mujer de 41 años, con gestación gemelar de 35 semanas, quien acudió al servicio de emergencia, por contracciones uterinas y ausencia de movimientos fetales. Ante una bradicardia severa de ambos fetos, se optó por una cesárea de urgencia. Al abrir la cavidad abdominal, se encontró hemoperitoneo y se logró extraer ambos fetos vivos. Se realizó una laparotomía media, supra e infraumbilical exploradora (poscesárea) y se halló una rotura hepática del lóbulo derecho. Se procedió a un empaquetamiento hepático con compresas y cierre temporal abdominal; entre tanto, el manejo del shock hipovolémico y la preeclampsia se continuó en la unidad de cuidados intensivos. La paciente se fue de alta en buenas condiciones a los 21 días. Conclusión: el síndrome HELLP produce complicaciones graves, como rotura hepática, que si no es tratada de forma correcta, temprana y multidisciplinaria, puede llevar a producir mortalidad materno-perinatal.

Introduction: HELLP syndrome and hepatic rupture are rare complications, especially in the case of twin pregnancy. Here, we present a case of ruptured hepatic subcapsular hematoma due to HELLP syndrome that caused complication in a twin pregnancy. This case required emergency Cesarean section and management of hypo- volemia hepatic packing. Case presentation: A 41-year-old female pregnant with twins (35 weeks) came to the emergency room for uterine contractions and absence of fetal movements. Due to severe bradycardia in both fetuses, emergency Cesarean section was performed. When the abdominal cavity was opened, hemoperitoneum was found, and both fetuses were extracted alive. A median, supra-, and infraumbilical exploratory laparotomy (post Cesarean section) was performed, and right lobe hepatic rupture was found. Subsequently, hepatic packing with compression and temporary abdominal closure was performed. Hypovolemic shock and preeclampsia was continuously managed in the intensive care unit. At 21 days, the patient was discharged in good condition. Conclusion: HELLP syndrome causes serious complications, such as hepatic rupture, which may lead to maternal and perinatal mortality if not correctly treated early in a multidisciplinary manner.

Introdução: a síndrome HELLP e a ruptura hepática são complicações raras, especialmente em casos de gravidez gemelar. Neste artigo, apresentamos o caso de um hematoma subcapsular hepático rompido devido à síndrome HELLP que complicou uma gravidez gemelar que exigiu uma cesariana de emergência e tamponamento hepático para o manejo da hipovolemia. Apresentação do caso: mulher, 41 anos, gestação gemelar de 35 semanas, recorre ao pronto-socorro por contrações uterinas e ausência de movimentos fetais. Devido à bradicardia grave em ambos os fetos, foi decidida uma cesariana de emergência. Ao abrir a cavidade abdominal o hemoperitônio é localizado, sendo possível extrair ambos os fetos vivos. Foi realizada laparotomia exploradora mediana, supra e infraumbilical (pós-cesariana) sendo constatada ruptura hepática do lobo direito. Foi realizado tamponamento hepático com compressas e fechamento abdominal temporário, e o manejo do choque hipovolêmico e da pré-eclâmpsia foi mantido na Unidade de Terapia Intensiva, onde a paciente recebeu alta em boas condições após 21 dias. Conclusão: a síndrome HELLP produz complicações graves como a ruptura hepática que, se não tratada de forma precoce e multidisciplinar, pode levar à mortalidade materna perinatal.

Biometry and pathological ultrasound findings in multiple pregnancies / Características ecográficas y hallazgos patológicos en embarazos múltiples

Resumo Objectives: to determine the prevalence of pathological findings according to the type of chorionicity in pregnancies in two institutions in Bogotá, Colombia. Methods: descriptive, retrospective, cohort study. Biometric variables were calculated, and pathological findings were evaluated according to the type of chorionicity in multiple pregnancies. Statistical characterization was performed with absolute frequencies, calculation of relative frequencies in qualitative variables, standard deviation measures, median and interquartile range. In addition, a descriptive analysis of the information was carried out. Results: 528 studies were carried out in 141 pregnant women, 98.5% (n = 139) twins and 1.4% (n = 2) triplets. A prevalence of 35.4% of fetal complications was calculated. The most frequent was fetal growth restriction (p=0.37). According to each type of chorionicity, fetal growth restriction was presented in 50% (1/2) of the trichorionics, 16.6% (7/42) of the monochorionics, and 11.3% (11/97) of the dichorionics. Conclusion: fetal growth restriction was the most common finding, both in trichorionics, monochorionics and dichorionics pregnancies.

Resumen Objetivos: el objetivo del estudio fue determinar la prevalencia de los hallazgos patológicos ecográficos en embarazos múltiples de acuerdo con la corionicidad en dos instituciones en Bogotá-Colombia. Métodos: estudio de cohorte, descriptivo, retrospectivo. Las variables biométricas realizadas y los hallazgos patológicos se evaluaron de acuerdo con el tipo de embarazo gemelar. Se realizó caracterización estadística con frecuencias absolutas, cálculo de frecuencias relativas en variables cualitativas, medidas de desviación estándar, mediana y rango intercuartílico. Además, se realizó análisis descriptivo de la información. Resultados: se realizaron 528 estudios en 141 gestantes, encontrando 98,5% (n=139) gemelares y 1,4% (n=2) triples. Se calculó una prevalencia de 35,4% de complicaciones fetales siendo más frecuente la restricción del crecimiento fetal (p=0,37). Según la corionicidad, esta complicación se presentó en 50% (1/2) de los tricoriónicos, 16,6% (7/42) de los monocoriónicos y 11,3% (11/97) de los dicoriónicos. Conclusión: la restricción del crecimiento fetal fue el hallazgo más común en los embarazos múltiples en la población estudiada.

HPLC-MS/MS method for determination of betamethasone in human plasma with application to a dichorionic twin pregnancy pharmacokinetic and placental transfers studies

Abstract Betamethasone (BET) is a synthetic glucocorticoid recommended for pregnant women at imminent risk of preterm birth before 34 weeks to reduce neonatal complications. There are different techniques to describe BET plasma quantification. However, none quantified the plasmatic concentration of BET in dichorionic (DC) twin pregnancies using LC-MS. Our objectives were to develop and validate a method for quantifying BET by LC-MS for pharmacokinetic (PK) and placental transfer studies in DC twin pregnancies. Blood samples were collected after intramuscular administration of a single BET dose containing 6 mg disodium phosphate + 6 mg acetate. BET was determined in plasma by liquid-liquid extraction. The method showed linearity in the range of 2-250 ng/mL, as well as precision and accuracy with a coefficient of variation and relative standard errors ≤ 15%. Additionally, the method presented selectivity and did not present matrix or carry-over effect. Stability tests also presented coefficient of variation and relative standard errors ≤ 15%. This is the first study which describe maternal and fetal plasma concentrations of BET in a DC twin pregnancy. The BET PK parameters were AUC0-∞, CL/F, Vd/F, Cmax, Tmax of 292.20 h*ng/mL, 39.08 L/h, 278.72 L, 25.55 ng/mL and 0.58 h, respectively. The placental transfer ratios of umbilical vein/maternal vein and intervillous space/maternal vein were 0.14 and 0.19 and 0.40 and 0.27 for both twins, respectively. However, a clinical study with more subjects is imperative to confirm this higher concentration of BET in the intervillous space

Characteristics of the oral glucose tolerance test in women with different pre-pregnancy body mass index and the effect of gestational diabetes mellitus on twin pregnancy outcomes

Abstract Objective This study aimed to investigate the mid-pregnancy blood glucose levels of women with singleton or twin pregnancies. Method The relationship between blood glucose levels and Gestational Diabetes Mellitus (GDM) was studied in women with different pre-pregnancy Body Mass Index (BMI), and the effect of GDM on twin pregnancy outcomes was analyzed. Women with twin (n= 1,985) and singleton (n= 1,985) pregnancies were categorized into underweight (BMI < 18.5 kg/m2, n= 597), normal weight (BMI: 18.5-23.9 kg/m2, n= 2,575), and overweight/obese (BMI ≥ 24 kg/m2, n= 798) groups. Results The incidence of GDM was 21.01% in women with twin pregnancies. Among the women with GDM in twin pregnancies, 38.37% had at least two abnormal blood glucose levels. The incidence of these parameters increased with preconception BMI, and the incidence of twin pregnancies was higher than that of singleton pregnancies (p < 0.001). In the normal weight and overweight/obese group, the oral glucose tolerance test glucose level and incidence of GDM were higher in women with twin than singleton pregnancies (p < 0.05). For twin pregnancies, the prevalence of selective fetal growth restriction was higher and anemia was lower in the GDM group than in the non-GDM group (all p < 0.05). Conclusion Therefore, a greater emphasis should be placed on BMI before conception, and well-controlled GDM does not increase adverse pregnancy outcomes for twin pregnancies.

Embarazo gemelar espontáneo en útero bicorpóreo: una contribución a la experiencia / Spontaneous twin pregnancy in a bicorporeal uterus, a contribution to the experience

Resumen ANTECEDENTES: Las anomalías uterinas congénitas son consecuencia de la formación anormal, fusión o reabsorción de los conductos de Müller durante el desarrollo embriológico. El útero bicorne, unicorne y didelfo (U1, U2, U3 ESHRE-ESGE) son defectos en la unificación con una baja prevalencia en la población general y en la que tiene antecedente de aborto e infertilidad; se estima en alrededor de 0.4 a 1.1%, respectivamente. La presentación del caso puede aportar información útil relacionada con la evolución del embarazo y los desenlaces perinatales cuando aparece esta anomalía. CASO CLÍNICO: Paciente de 35 años, con amenorrea secundaria y prueba inmunológica de embarazo positiva, con antecedentes de dismenorrea primaria severa y anomalía uterina congénita compatible con útero bicorpóreo (U3 completo ESHRE-ESGE), bicorne completo (4a-AFS) y didelfo. El embarazo trascurrió sin complicaciones hasta la semana 37, cuando finalizó mediante cesárea, con hipotonía uterina que no ameritó transfusión de hemoderivados. CONCLUSIÓN: Los embarazos gemelares con útero bicorne son excepcionales y casi todos se logran espontáneamente; los que llegan a término finalizan mediante cesárea electiva.

Abstract BACKGROUND: Congenital uterine anomalies are the result of abnormal formation, fusion, or resorption of the Müllerian ducts during embryological development. The bicornuate, unicornuate and didelphic uterus (U1, U2, U3 ESHRE/ESGE), are unification defects with a low prevalence both in the general population and in the population with a history of abortion and infertility, is estimated at around 0.4 to 1.1%, respectively. The presentation of the case can provide useful information related to with the evolution of the pregnancy and the perinatal outcomes when this anomaly appears. CLINICAL CASE: A 35-year-old patient with secondary amenorrhea and a positive immunological pregnancy test with a history of severe primary dysmenorrhea and previous magnetic resonance imaging with a congenital uterine anomaly compatible with a bicorporeal uterus (U3 complete ESHRE-ESGE), complete bicornuate (4a /AFS) , uterus didelphys (ASRM). The pregnancy was uncomplicated until 37 weeks, when it was terminated by cesarean section, with uterine hypotonia that did not require transfusion of blood products. CONCLUSION: Twin pregnancy with bicornuate uterus is a rare entity, most of them have been achieved spontaneously and those that reach term have been resolved by elective cesarean section.

Manejo das principais anormalidades gestacionais em éguas / Management of the main gestational abnormalities in mares

A produção de potros é o objetivo final de todas as atividades voltadas para a reprodução equina. Para tanto, o diagnóstico de anormalidades gestacionais deve ser realizado precocemente para que a instalação da terapêutica adequada seja garantida, visando manter a sobrevivência da égua e o nascimento de indivíduos vivos e saudáveis. Aqui encontram-se descritos os principais achados relacionados às anormalidades gestacionais de éguas mais frequentemente encontradas em atendimentos realizados a campo e nas rotinas hospitalares. São elas: gestação gemelar, placentite, separação prematura da placenta, torção uterina, hidropsias e ruptura de tendão pré-púbico. O objetivo é caracterizar os sinais clínicos, métodos diagnósticos, tratamento e prognóstico dessas enfermidades. A compreensão desses aspectos é essencial para o desenvolvimento de estratégias de prevenção e gestão das intercorrências obstétricas, visando reduzir seu impacto na criação de equinos.(AU)

The primary objective of equine reproduction is to produce healthy foals. To achieve this, it is crucial to diagnose gestational abnormalities at an early stage and administer appropriate therapy. This will increase the chances of survival for the mare and the birth of live foals. Here we outlines the most frequently observed gestational abnormalities in mares during field visits and hospital routines. The following abnormalities discussed are: twin pregnancy, placenta problems, premature separation of the placenta, uterine torsion, hydrops, and rupture of the prepubic tendon. The objective is to characterize the clinical signs, diagnostic methods, treatment, and prognosis for each of these conditions. It is essential to understand these aspects of gestational abnormalities to develop effective prevention and management strategies for obstetric complications. aiming to reduce their impact on equine breeding.(AU)

External cephalic version for a malpresenting first twin before labor: a prospective case series.

BACKGROUND: In twin pregnancies where the presenting twin is not cephalic, cesarean delivery is the standard of care. External cephalic version (ECV) has been used for malpresenting singleton pregnancies with low risk of complications. ECV in twin pregnancies is poorly studied. OBJECTIVE: To assess feasibility and report any complications of ECV of a malpresenting twin before labor. STUDY DESIGN: This is a prospective cohort of twin pregnancies with malpresenting first twin. Inclusion criteria included English or Spanish speaking women. Exclusions included cases where there was a contraindication to vaginal delivery. ECV was performed according to the institutional singleton protocol. Fetal testing of both twins was performed before and after procedure. A vaginal hand was used during ECV as needed. The primary outcome was success of the procedure. Secondary outcomes included delivery characteristics and neonatal outcomes. RESULTS: Five patients were enrolled in this study. Four patients underwent successful ECV and vaginal delivery occurred in 2 of the 4 patients. ECV procedure was performed at a mean gestational age of 36+0 weeks in the successful ECV group and 36+6/7 weeks for the unsuccessful group. Latency to delivery was 4.5 days in the successful ECV group and 1 day in the unsuccessful ECV group. No maternal or neonatal complications occurred in any participating women. CONCLUSION: ECV in twin pregnancies where the first twin is malpresenting was feasible in our cohort. More research is needed to better characterizer the safety and efficacy of this procedure in this patient population.

Útero bicorporeo - doble cérvix con embarazo gemelar en una sola cavidad uterina: reporte de caso / Bicorporeo uterus - double cervix with twin pregnancy in a single uterine cavity: case report

El embarazo gemelar en una de las cavidades uterinas del útero bicorpóreo es una rara presentación clínica. La viabilidad de este tipo de embarazo es de baja probabilidad, dado que esta malformación puede condicionar parto prematuro, placentación anormal, restricción del crecimiento fetal o progresión anormal del trabajo de parto. Se presenta un caso de un útero bicorpóreo con doble cérvix y una gestación gemelar en unas de las cavidades uterinas, con muerte fetal de uno de los fetos y parto pretérmino de 28 semanas del otro gemelo. Dada la rareza de la presentación se describen el caso y los hallazgos imagenológicos representativos.

Twin pregnancy in one of the uterine cavities of the bicoporous uterus is a rare clinical presentation. The viability of this type of pregnancy is unlikely since this malformation can lead to premature delivery, abnormal placentation, fetal growth restriction or abnormal progression of labor. We present a case of bicoporous uterus with double cervix with twin pregnancy in one of the uterine cavities, with stillbirth of one of the fetuses and preterm delivery of the other twin at 28 weeks. Given the rarity of the presentation, the case and representative imaging findings are described.

Anastomosis placentarias en embarazos gemelares monocoriales: estudio mediante técnicas de inyección vascular y relación con complicaciones fetales / Placental anastomoses in monochorionic twin pregnancies: study using vascular injection techniques and relationship with fetal complications

RESUMEN Introducción. Los embarazos gemelares son clasificados en dos grupos: monocoriónico (MC) y dicoriónico (DC). Los gemelos MC tienen 5 a 6 veces más riesgo de tener un resultado perinatal adverso. Se publica el estudio de un grupo de 22 placentas de pacientes con embarazo gemelar monocoriónico que presentaron complicaciones como síndrome de transfusión feto-fetal (STFF), secuencia de anemia policitemia (TAPS), perfusión arterial reversa (TRAP) y restricción de crecimiento intrauterino selectivo (RCIU-s). Objetivo . Determinar los tipos de anastomosis predominantes en las placentas con síndrome de transfusión feto-fetal, secuencia de anemia policitemia, síndrome de perfusión arterial reversa y restricción de crecimiento selectivo. Metodología . Se aplicó la técnica de inyección vascular placentaria para el reconocimiento de las anastomosis. Resultados . El número medio de anastomosis por placenta en el STFF (que fue la complicación más severa) fue de 8,2 ± 2,2. Las anastomosis AV y VA predominaron en un 83%. Hubo signos de discordancia placentaria en 30% de las placentas, y un 40% de placentas presentaron cordón de inserción velamentosa. Conclusiones. Las anastomosis vasculares no solo están implicadas en la etiología de las principales patologías propias de gestaciones monocoriónicas, sino que también influyen en su manejo. Creemos que un adecuado estudio placentario de cada uno de estos casos mediante la técnica de inyección vascular placentaria sería indispensable en los centros que aspiran a desarrollar manejos diferenciados de terapia fetal para cada una de estas complicaciones.

ABSTRACT Introduction: Twin pregnancies are classified into two groups: monochorionic (MC) and dichorionic (DC). MC twins are 5 to 6 times more likely to have an adverse perinatal outcome. The study of a group of 22 placentas from patients with monochorionic twin pregnancy who presented with complications such as feto-fetal transfusion syndrome (FFTS), twin anemia polycythemia sequence (TAPS), twin reverse arterial perfusion syndrome (TRAP) and selective intrauterine growth restriction (sIUGR) is presented. Objective: To determine the predominant types of anastomoses in placentas with feto-fetal transfusion syndrome, twin anemia polycythemia sequence, reverse arterial perfusion syndrome and selective intrauterine growth restriction. Methodology: The placental injection technique was applied for the recognition of anastomoses. Results: The mean number of anastomoses per placenta in STFF, which was the most severe complication, was 8.2 ± 2.2. The AV and VA anastomoses predominated in 83%. There were signs of placental discordance in 30% of placentas, and 40% of placentas presented velamentous cord insertion. Conclusions: Vascular anastomoses are not only involved in the etiology of the main pathologies of monochorionic gestations, but also influence their management. We believe that an adequate placental study of each of these cases by means of the placental vascular injection technique would be essential in centers that aspire to develop differentiated fetal management for each of these complications.

Enhanced elimination of betamethasone in dichorionic twin pregnancies.

AIM: No study has evaluated the betamethasone pharmacokinetics in twin pregnancies according to chorionicity. This study aimed to describe and compare the betamethasone pharmacokinetic parameters in singleton and dichorionic (DC) and monochorionic twin pregnancies in the third trimester of pregnancy. METHODS: Twenty-six pregnant women received 2 intramuscular doses of 6 mg of betamethasone sodium phosphate plus 6 mg betamethasone acetate due to preterm labour. Serial blood samples were collected for 24 hours after the first intramuscular dose of betamethasone esters. Betamethasone plasma concentrations were quantified using a validated liquid chromatography-tandem mass spectrometry analytical method, and the pharmacokinetic parameters were obtained employing a noncompartmental model. Preliminary data on the betamethasone placental transfer are also presented. RESULTS: The geometric mean (95% confidence interval) of AUC0-∞ 645.1 (504.3-825.2) vs. 409.8 (311.2-539.6) ng.h/mL and CL/F 17.70 (13.84-22.65) vs. 27.87 (21.17-36.69) were significantly different, respectively, in singleton pregnancies when compared to DC twins. CONCLUSION: Data from this study suggest that the presence of 2 foetoplacental units may increase the betamethasone metabolism by hepatic CYP3A4 and/or placental 11ß-HSD2 enzymes. Pharmacokinetic-pharmacodynamic clinical studies are needed to investigate whether these betamethasone pharmacokinetic changes have clinical repercussions for the newborns and require dose adjustment in DC twin pregnancies.

Clinical analysis on the influencing factors related to preterm twin pregnancy

SUMMARY OBJECTIVE: The aim of this study was to explore the influencing factors of preterm twin pregnancy. METHODS: In total, 602 twin-pregnant women delivered from February 2016 to February 2020 were analyzed retrospectively. According to whether the pregnant women were preterm or not, they were divided into preterm group (n=363) and term group (n=239). Baseline information, such as maternal age, address, and education level of the pregnant women, were collected. The clinical information of pregnant women, such as chorionic, preeclampsia, gestational diabetes, premature rupture of membranes, abnormal fetal position, and fetal weight, were analyzed. Logistic regression analysis was used to analyze the risk factors. p-value <0.05 was considered statistically significant. RESULTS: In the preterm group, monochorionic diamniotic comorbidities were significantly higher compared with the control group (p<0.05). Higher risks of preterm group have lower education (p<0.05). Multiple logistic regression analysis demonstrated that education, preeclampsia, and premature rupture of membranes were risk factors for preterm twin pregnancy. CONCLUSIONS: Preterm birth in twin pregnancy is associated with many risk factors, such as education, preeclampsia, and premature rupture of membranes. Pregnancy supervision and prenatal guidance for twin pregnancy should be strengthened. Furthermore, early detection and diagnosis of comorbidities can improve maternal and neonatal outcomes.

Bases informacionales para el estudio morfométrico de placentas en embarazos gemelares

RESUMEN Introducción: En Cuba existen muy pocos estudios morfofuncionales de placentas procedentes de embarazos gemelares que permitan establecer un patrón morfométrico general. Implementar estas bases informacionales contribuiría a perfeccionar las acciones del Programa Nacional de Salud Sexual y Reproductiva en el país. Objetivo: Sistematizar información sobre estudios morfométricos en placentas gemelares para construir la base epistémica de la caracterización del patrón morfométrico de las placentas gemelares y su relación con la corionicidad, la función de este órgano y el grado de bienestar fetal y neonatal. Método: Se aplicó una estrategia de búsqueda en el período enero de 2020 hasta abril de 2021, en bases de datos internacionales (Medline, EMBASE, LILACS, Scopus, Google Académico) para la revisión bibliográfica, mediante la utilización del método de análisis y crítica de las fuentes desde el procedimiento de análisis de contenido. Se empleó un algoritmo para la toma de decisiones en torno a la pertinencia, actualidad novedad y aportes. Resultados: Se hallaron 16 fuentes bibliográficas sobre el tema de investigación, entre ellas: solo una tesis (6,25 %) y 4 textos editados (25 %). Predominaron los artículos científicos (68,75 %) de los últimos cinco años (93,75 %). Todas las fuentes contribuyeron a la construcción de los referentes teóricos. Conclusiones: El estudio morfométrico de la placenta en embarazos gemelares es un área insuficientemente desarrollada en el conocimiento de las ciencias básicas biomédicas, dada la escasa producción bibliográfica sobre el tema.

ABSTRACT Introduction: In Cuba there are very few morphofunctional studies of placentas from twin pregnancies that allow establishing a general morphometric pattern. Implementing these informational databases would help to improve the actions of the National Sexual and Reproductive Health Program in the country. Objective: To systematize information on morphometric studies in twin placentas to build the epistemic basis for the characterization of the morphometric pattern of twin placentas and its relationship with chorionicity, the function of this organ and the degree of fetal and neonatal well-being. Method: A search strategy was applied in the period January 2020 to April 2021, in international databases (Medline, EMBASE, LILACS, Scopus, Google Scholar) for the bibliographic review, using the analysis and criticism method. of the sources from the content analysis procedure. An algorithm was used to make decisions about relevance, news, news and contributions. Results: 16 bibliographic sources were found on the research topic, among them: only one thesis (6.25%) and 4 edited texts (25.0%). Scientific articles (68.75%) from the last five years (93.75%) predominated. All the sources contributed to the construction of the theoretical referents. Conclusions: The morphometric study of the placenta in twin pregnancies is an insufficiently developed area in the knowledge of basic biomedical sciences, given the scarce bibliographic production on the subject.

RESUMO Introdução: Em Cuba existem poucos estudos morfofuncionais de placentas de gestações gemelares que permitam estabelecer um padrão morfométrico geral. A implementação desses bancos de dados informativos ajudaria a melhorar as ações do Programa Nacional de Saúde Sexual e Reprodutiva no país. Objetivo: Sistematizar informações sobre estudos morfométricos em placentas gêmeas para construir a base epistêmica para a caracterização do padrão morfométrico de placentas gêmeas e sua relação com a corionicidade, a função desse órgão e o grau de bem-estar fetal e neonatal. Método: Foi aplicada uma estratégia de busca no período de janeiro de 2020 a abril de 2021, em bases de dados internacionais (Medline, EMBASE, LILACS, Scopus, Google Scholar) para a revisão bibliográfica, utilizando o método de análise e crítica das fontes da análise de conteúdo procedimento. Um algoritmo foi usado para tomar decisões sobre relevância, notícias, notícias e contribuições. Resultados: Foram encontradas 16 fontes bibliográficas sobre o tema da pesquisa, entre elas: apenas uma tese (6,25%) e 4 textos editados (25,0%). Predominaram artigos científicos (68,75%) dos últimos cinco anos (93,75%). Todas as fontes contribuíram para a construção dos referentes teóricos. Conclusões: O estudo morfométrico da placenta em gestações gemelares é uma área pouco desenvolvida no conhecimento das ciências biomédicas básicas, dada a escassa produção bibliográfica sobre o assunto.

Importancia social del estudio morfométrico en placentas procedentes de embarazos gemelares / Social importance of the morphometric study in placentas from twin pregnancies / Importância social do estudo morfométrico em placentas de gestações gemelares

RESUMEN Se fundamenta la necesidad de la investigación científica para el estudio morfométrico en placentas procedentes de embarazos gemelares, como aproximación a la correlación entre el patrón morfométrico, la corionicidad y el bienestar fetal y neonatal, en tanto criterios básico/clínicos a tomar en cuenta para perfeccionar las acciones del programa nacional de salud sexual y reproductiva en Cuba. Se destaca la importancia social de un diseño de investigación en este campo, al constatar las carencias epistémicas desde una búsqueda sistematizada de información bibliográfica sobre el tema.

ABSTRACT The need for scientific research for the morphometric study in placentas from twin pregnancies is founded, as an approximation to the correlation between the morphometric pattern, chorionicity and fetal and neonatal well-being, as basic / clinical criteria to be taken into account to improve the actions of the national sexual and reproductive health program in Cuba. The social importance of a research design in this field is highlighted, when verifying the epistemic deficiencies from a systematized search of bibliographic information on the subject.

RESUMO Fundamenta-se a necessidade de pesquisas científicas para o estudo morfométrico em placentas de gestações gemelares, como uma aproximação da correlação entre o padrão morfométrico, corionicidade e bem-estar fetal e neonatal, como critérios básicos / clínicos a serem levados em consideração para melhorar a ações do programa nacional de saúde sexual e reprodutiva em Cuba. Ressalta-se a importância social de um desenho de pesquisa nessa área, ao verificar as deficiências epistêmicas a partir de uma busca sistematizada de informações bibliográficas sobre o assunto.

Maternal and Perinatal Factors Associated With Twin Pregnancies in Ecuador.

There are few studies on twins in Ecuador and Latin America. It requires a better understanding of perinatal conditions, especially from an ethnic perspective. This work aims to assess perinatal factors related to twin pregnancy in Ecuadorian Mestizo individuals. We performed an epidemiological, observational and cross-sectional study at the Hospital San Francisco and Hospital Nueva Aurora in Quito, Ecuador, from November 2019 to January 2020. It included 203 newborns from twin pregnancies, including mothers with and without pathological history. The average gestational age was 31 weeks, and the APGAR score at first minute was 6.86, with significant differences. Regarding the metabolic balance, the mean pH was 6.14; and bicarbonate was 11.57, with significant differences. Twins had intrauterine growth restriction in 6.9% of cases, with significant differences (p = .003); 81.4% required supplemental oxygen, with significant differences (p = .002); 93% required noninvasive mechanical ventilation (NIMV), with significant differences (p = . 003); 93% required inotropic and sedation, with substantial differences; 69% required antibiotics (≥21 days), with significant differences (p = .014); and 17.2% needed between 8 to 14 days of hospitalization, and 51% more than 28 days, with significant differences. The studied mothers' demographic profile was mostly Mestizos, with an average age of 32 years, and 93% had a poverty status. Most of the twins were diamniotic monochorial and were discordant twins. It found jaundice, premature anemia and sepsis in 100% of twins and hyaline membrane disease in 89.66% of twins. Twins of women with relevant prenatal care had more premature births (30.4 ± 2.6 weeks), more acid-base imbalance, APGAR at ≥7 min in 90% of cases, and patent ductus arteriosus in all. There was also a greater need for double intensive phototherapy than twins of healthy women.