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.

Diagnóstico de malformación del desarrollo cortical en embarazo gemelar monocorial: reporte de caso / Diagnosis of malformation of the cortical development in a monochorial twin pregnancy: case report

Introducción: Las malformaciones del desarrollo cortical se deben a alteraciones en la migración del neuroblasto durante la formación de la corteza cerebral. Se desconoce su frecuencia en embarazos monocoriales. Objetivo: Reportar el caso de un embarazo monocorial con diagnóstico de malformación del desarrollo cortical en uno de los fetos y revisar la literatura referente a su diagnóstico y pronóstico. Método: Mujer de 19 años, embarazo monocorial biamniótico de 26 semanas, que acudió con estudio ecográfico y resonancia fetal que evidenció en uno de los fetos asimetría de los hemisferios cerebrales, hipoplasia de la cisura de Silvio izquierda con simplificación del patrón giral por focos de paquigiria y polimicrogiria, con confirmación posnatal de alteración en la migración neuronal asociada a hipoplasia vermiana. Resultados: Se encontraron en la literatura tres casos de embarazo múltiple monocorial con trastorno de la migración neuronal con recién nacidos vivos. Los hallazgos más comunes fueron microcefalia, lisencefalia e hipoplasia cerebelosa. Conclusiones: El diagnóstico prenatal del trastorno de la migración neuronal se realiza con ecografía y resonancia fetal. La más frecuente es la alteración de la migración neuronal tipo II. El pronóstico depende del tipo de alteración; sin embargo, la mayoría de los casos presentan trastornos epileptiformes con alteraciones del neurodesarrollo.

Introduction: Malformations of cortical development are the result from alterations in the neuroblast migration during the cerebral cortex formation. Its frequency in monochorial multiple pregnancies remains unknown. Objective: To report a case of monochorial multiple pregnancy with diagnosis of malformation of the cortical development in one of the fetuses. In addition, to review the literature regarding the diagnosis and prognosis of this entity. Method: A 19-year-old female with a monochorial diamniotic pregnancy of 26 weeks gestation, arrived with an ultrasound anatomy scan visit, and fetal magnetic resonance imaging, we detected asymmetry in the cerebral hemispheres one of the fetuses, hypoplasia of the left sulcus of Sylvius with simplification of the gyrus pattern due to clusters of pachygyria and polymicrogyria. Those findings were confirmed afterbirth, with a definite diagnosis of neuronal migration disorder associated with vermian hypoplasia. Results: Three cases of monochorial pregnancy with neuronal migration disorder with live newborn, common findings like microcephaly, lissencephaly and vermian hypoplasia. Conclusions: Prenatal diagnosis with neuronal migration disorder is done via ultrasound and magnetic resonance imaging. Neuronal migration disorders type II are the most common of them. Prognosis depends on the type of disorder; however, most patients have epileptiform activity and neurodevelopment impairment.

Clinical application of non-invasive prenatal testing for twin pregnancies / 中华医学遗传学杂志

OBJECTIVE@#To evaluate the feasibility of non-invasive prenatal testing (NIPT) for the screening of fetal chromosome aneuploidies in twin pregnancies.@*METHODS@#A total of 2 745 women with twin-pregnancies were subjected for NIPT screening. Chromosomal karyotyping and chromosomal microarray analysis (CMA) were carried out on amniotic fluid samples from those with a high risk for fetal chromosome aneuploidies, and the diagnosis and pregnancy outcome were followed up. The sensitivity, specificity, positive predictive value and false positive rate of the NIPT were calculated.@*RESULTS@#Compared with other chromosomal abnormalities, NIPT had a higher efficacy for trisomy 21 and sex chromosomal aneuploidy (SCA) in twin pregnancies (with sensitivity being 100%, 100%, and specificity being 99.93%, 99.9%, respectively). It is difficult to evaluate the efficacy for trisomies 18 and 13 due to the limited data. For chromosome microdeletions and microduplications spanning 15 ~ 21 Mb, NIPT also had a certain detection rate. Compared with women with natural conception, NIPT had a higher detection rate for those with twin pregnancies by assisted reproduction (P < 0.05).@*CONCLUSION@#It is feasible to use NIPT for the detection of chromosome aneuploidies in women with twin pregnancies.

Placental mosaicism in multiple gestation: Complete hydatidiform mole with coexisting twin fetus

@#Hydatidiform mole coexistent with a live fetus (CMCF) is a rare entity occurring in 1:20,000 to 1:100,000 pregnancies. Three mechanisms of this type are possible: (1) a singleton pregnancy consisting of partial mole with a triploid fetus, (2) a twin gestation consisting of an androgenic complete hydatidiform mole with a biparental diploid fetus, and (3) a twin gestation consisting of a biparental diploid fetus with a normal placenta and a partial hydatidiform mole (PHM) with a triploid fetus. The abnormal triploid fetus in a partial mole tends to die in the first trimester while the fetus coexisting with a complete or partial mole in the dizygotic twin pregnancy has a chance to survive. Early detection and diagnosis of a molar gestation with a viable fetus is needed to allow medical interventions, if available. Three cases of complete mole with a twin fetus (CMTF) that were diagnosed in the prenatal period by ultrasonography will be presented. This report will also discuss the indications for continuing the pregnancy, and review the literature on the recommended prenatal care, intrapartum management, and postpartum surveillance. This report aims to encourage others to document cases of CMTF in order to arrive at a consensus regarding its optimal management.

Clinical analysis of 102 cases of labor induction in the third trimester on twin pregnancy / 中华妇产科杂志

Objective: To investigate the clinical characteristics of induced labor in twin pregnancy and the related factors of induced labor failure. Methods: The clinical data of twin pregnant women who underwent induced labor in Peking University Third Hospital from January 2016 to December 2022 were retrospectively analyzed. According to whether they had labor or not after induction, pregnant women were divided into the success group (pregnant women who had labor after induction, 72 cases) and the failure group (pregnant women who did not have labor after induction, 30 cases). Logistic regression was used to analyze the related factors of induction failure in twin pregnant women. Results: The parity and cervical Bishop score in the failure group were significantly lower than those in the success group, while the proportion of dichorionic diamniotic twins, assisted reproductive technology pregnancy and cervical Bishop score <6, postpartum hospital stay and total hospital stay in the failure group were significantly higher than those in the success group (all P<0.05). The proportion of induced labor by artificial rupture of membranes ± oxytocin intravenous infusion in the success group was 72.2% (52/72), which was significantly higher than that in the failure group (46.7%, 14/30; P=0.030). There were no significant differences between the two groups in the gestational age at delivery, the incidence of severe postpartum hemorrhage and blood transfusion, the amount of postpartum hemorrhage, the neonatal weight of two fetuses, the incidence of neonatal asphyxia, and the proportion of neonates admitted to the neonatal intensive care unit (all P>0.05). There were no severe perineal laceration and hysterectomy in all pregnant women. Multivariate logistic regression analysis showed that primipara (OR=3.064, 95%CI: 1.112-8.443; P=0.030) and cervical Bishop score <6 (OR=5.208, 95%CI: 2.008-13.508; P=0.001) were the independent risk factors for induction failure in twin pregnancy. Conclusions: Elective induction of labor in twin pregnancy is safe and feasible. It is helpful to improve the success rate of induction of labor by strictly grasping the timing and indications of termination of pregnancy, choosing the appropriate method of induction according to the condition of the cervix, and actively promoting cervical ripening .

Cojoined twins: safe termination of pregnancy through dilation and evacuation at later gestation: a case series

BACKGROUND: Currently, there is limited evidence on termination of pregnancy for cojoined twin documented with only 33 cases reports to-date. This study aimed to describe the clinical and procedure characteristics of second trimester dilation and evacuation(D&E) for cojoined twins at later gestation. METHODS: This retrospective case series was conducted at a tertiary-level hospital in Ethiopia from February 2023- July 2023. Women who had a cojoined twin pregnancy in later gestation (≥20 weeks) and underwent second trimester D&E were retrospectively studied through chart review. Clinical presentation, D&E procedural description, and procedure outcomes of the cases were analyzed. RESULTS: Three women who had a cojoined twin in later gestation (≥20 weeks) and underwent second trimester D&E were identified. In two of the cases, a two- day cervical preparation with laminaria was used to prepare the cervix while overnight Foley catheter (1-day preparation) was used for similar purpose in the third case. A cervical dilation of 3 cm was achieved in all cases and was deemed adequate to proceed with the procedure by the managing physicians. Intra-operative ultrasound guidance was utilized in all the cases and there were no complications encountered. CONCLUSION: Our case series underscores the importance of achieving adequate cervical preparation, utilization of intra-operative ultrasound guidance, and handling the procedure by the most experienced provider, in increasing the safety and effectiveness of D&E procedures for conjoined twin at later gestation.

Estereología en placentas procedentes de gestaciones gemelares / Stereology in placentas from twin pregnancies

Introducción: La disfunción placentaria origina complicaciones fetales; de manera más frecuente, la restricción del crecimiento intrauterino y la preclampsia. Objetivo: Identificar el patrón estereológico en placentas gemelares, y su relación con la corionicidad y el peso del recién nacido. Métodos: Se realizó un estudio descriptivo en una muestra de 16 gestantes gemelares, 25 placentas y 32 recién nacidos. Se estudiaron las variables peso del recién nacido, número de vellosidades, superficie vellositaria total, área vellositaria, área de nodos, densidad óptica de fibrina en la superficie vellositaria y densidad óptica de fibrina alrededor del vaso. Resultados: Existió relación directa entre el número de vellosidades y la superficie vellositaria total. En las placentas monocoriónicas hubo predominio de recién nacidos bajo peso. Se percibe una diferencia en los resultados de área, según el tipo placentario y la región topográfica. En las placentas monocoriales se observó mayor área, tanto de la vellosidad placentaria como en los nodos sincitiales, siendo el área de la vellosidad mayor en la periferia placentaria, y el área de nodos sincitiales en la región 4 cm del cordón umbilical. Conclusiones: La estereología microscópica a nivel pericordón, a 4 cm del cordón y en la periferia del disco placentario, arrojó diferencias significativas para el área de la vellosidad y la densidad óptica de fibrina en la superficie de la vellosidad. Los valores promedio para el área de nodos sincitiales y la densidad óptica de fibrina alrededor del vaso no mostraron diferencias estadísticamente significativas. Es la corionicidad un predictor del bajo peso al nacer(AU)

Introduction: Placental dysfunction causes fetal complications; more frequently, intrauterine growth restriction and preeclampsia. Objective: To identify the stereological pattern in twin placentas, and its relationship with chorionicity and weight of the newborn. Methods: A descriptive study was carried out in a sample of 16 women with twin pregnancy, 25 placentas and 32 newborns. The variables weight of the newborn, number of villi, total villous surface, villous area, node area, optical density of fibrin on the villous surface and optical density of fibrin around the vessel were studied. Results: There was a direct relationship between the number of villi and the total villous surface. In monochorionic placentas there was a predominance of low birth weight newborns. A difference is observed in the area results according to the placental type and the topographic region. In monochorionic placentas, a greater area was observed, both in the placental villus and in the syncytial nodes, with the villus area being greater in the placental periphery and the area of syncytial nodes in the region 4 cm from the umbilical cord. Conclusions: Microscopic stereology at the perichordal level, 4 cm from the cord and at the periphery of the placental disc showed significant differences for the villus area and fibrin optical density on the villus surface. The average values for the area of syncytial nodes and the optical density of fibrin around the vessel did not show statistically significant differences. Chorionicity is a predictor of low birth weight(AU)

Morfometría en placentas procedentes de embarazos gemelares / Morphometry in placentas from twin pregnancies

Introducción: La disfunción de la placenta puede originar complicaciones fetales, restricción del crecimiento intrauterino y complicaciones maternas, como la preeclampsia. Objetivo: Identificar el patrón morfométrico de las placentas gemelares y su relación con la corionicidad, el peso del recién nacido y las malformaciones plancentarias. Método: Se realizó un estudio descriptivo en una muestra de 16 gestantes con embarazo gemelar, 25 placentas y los 32 recién nacidos. Se estudiaron las variables malformaciones placentarias, tipo de placenta, presencia de calcificaciones, peso del recién nacido, peso de la placenta, volumen placentario, diámetro placentario y espesor placentario; se determinó la asociación del peso del recién nacido, con el tipo de placenta y la presencia de calcificaciones, las malformaciones placentarias, así como espesor, diámetro, volumen y peso, con el tipo de placenta. Resultados: Hubo mayor frecuencia de recién nacidos de placentas monocoriónicas (60 por ciento) sin que la asociación fuera estadísticamente significativa; las malformaciones placentarias se relacionaron de forma significativa con el tipo de placenta, así como el peso del recién nacido y la presencia de calcificaciones placentarias, y el espesor, diámetro, volumen y peso de la placenta, con el tipo de plancenta (p< 0,01). Conclusiones: Son más frecuentes las placentas dicoriónicas y estas tienen menos malformaciones; existe relación entre el bajo peso del recién nacido y la presencia de calcificaciones placentarias, así como entre el espesor, diámetro, volumen y peso de la placenta, con el tipo de placenta(AU)

Introduction: Placental dysfunction can originate fetal complications, intrauterine growth restriction and maternal complications, such as preeclampsia. Objective: To identify the morphometric pattern of twin placentas and its relationship with chorionicity, newborn weight and placental malformations. Methods: A descriptive study was carried out in a sample of 16 pregnant women with twin pregnancy, 25 placentas and 32 newborns. The variables placental malformations, type of placenta, presence of calcifications, newborn weight, placental weight, placental volume, placental diameter and placental thickness were studied; the association of newborn weight with the type of placenta and the presence of calcifications, placental malformations, as well as thickness, diameter, volume and weight, with the type of placenta was determined. Results: There was a higher frequency of newborns with monochorionic placentas (60 percent) without the association being statistically significant; placental malformations were significantly related to placenta type, as well as newborn weight and the presence of placental calcifications, and placental thickness, diameter, volume and weight, with placenta type (p< 0.01). Conclusions: Dichorionic placentas are more frequent and these have fewer malformations; there is a relationship between low newborn weight and the presence of placental calcifications, as well as between placental thickness, diameter, volume and weight, with the type of placenta(AU)

Analysis of typing conversion and perinatal outcomes in twins with selective intrauterine growth restriction of different subtypes / 中华妇产科杂志

Objective: To retrospectively analyze the clinical data of different types of selective intrauterine growth restriction (sIUGR) pregnant women under expectant management, including the natural evolution, typing conversion and perinatal outcomes. Methods: The clinical data of 153 pregnant women with sIUGR under expected treatment in Women's Hospital, Zhejiang University School of Medicine from January 2014 to December 2018 were collected. Maternal characteristics including maternal age, gravidity, parity, method of conception, pregnancy complication, gestational age at delivery, indication for delivery, birth weight, the rate of intrauterine and neonatal death and neonatal outcomes were recorded. Pregnant women with sIUGR were divided into three types according to end-diastolic umbilical artery flow Doppler ultrasonography, and the differences of typing conversion and perinatal outcomes of sIUGR pregnant women based on the first diagnosis were compared. Results: (1) Clinical characteristics and pregnancy outcomes: among 153 pregnant women with sIUGR, 100 cases (65.3%) were diagnosed with type Ⅰ, 35 cases (22.9%) with type Ⅱ, and 18 cases (11.8%) with type Ⅲ. There were no significant differences in age, conception mode, pregnancy complications, first diagnosis gestational age, characteristics of umbilical cord insertion, delivery indications, fetal intrauterine mortality and neonatal mortality among three types of sIUGR pregnant women (all P>0.05). The average gestational age at delivery of type Ⅰ sIUGR was (33.5±1.9) weeks, which was significantly later than those of type Ⅱ and Ⅲ [(31.3±1.8), (31.2±1.1) weeks, P<0.001]. The percentage disordance in estimated fetal weight (EFW) of type Ⅰ sIUGR was significantly lower than those of type Ⅱ and type Ⅲ (P<0.001). The incidence rate of neonatal intensive care unit (NICU) admission, cerebral leukomalacia and respiratory complications of both fetus and necrotizing enterocolitis of large fetus in type Ⅰ were significantly lower than those in type Ⅱ and type Ⅲ (all P<0.05). (2) Typing conversion: in 100 cases of type Ⅰ sIUGR, 18 cases progressed to type Ⅱ and 10 cases progressed to type Ⅲ. Compared with 72 stable type Ⅰ sIUGR, those with progressed type Ⅰ sIUGR had higher incidence of NICU admission and lung disease in both fetuses, and cerebral leukomalacia and necrotizing enterocolitis in large fetus (all P<0.05). The proportion of inconsistent cord insertion was significantly higher in those type Ⅰ progressed to type Ⅲ (6/10) than in those with stable type Ⅰ (19.4%, 14/72) and type Ⅰ progressed to type Ⅱ sIUGR [0 (0/18), P=0.001]. Four cases of type Ⅱ sIUGR reversed to type Ⅰ and 6 cases reversed to type Ⅲ. Compared with type Ⅱ reversed to type Ⅰ sIUGR, those stable type Ⅱ and type Ⅱ reversed to type Ⅲ sIUGR had a higher incidence of NICU admission in large fetus (P<0.05). Two cases of type Ⅲ sIUGR reversed to type Ⅰ and 6 cases progressed to type Ⅱ. There were no significant differences in fetal serious complications in type Ⅲ sIUGR with or without doppler changes (all P>0.05). Conclusions: The different types of sIUGR could convert to each other. The frequency of ultrasound examinations should be increased for patients with the type Ⅰ sIUGR, especially when the percentage discordance in EFW is substantial or with discordant cord insersion.

Exploration of factors for failure of non-invasive prenatal testing based on Logistic regression analysis / 中华医学遗传学杂志

OBJECTIVE@#To explore the factors for the failure of non-invasive prenatal testing (NIPT) through multifactorial unconditional Logistic regression analysis.@*METHODS@#A total of 3 410 pregnant women who had visited Dalian Women and Children Medical Group from July 2019 to June 2020 were selected as the study subjects and divided into first success NIPT group (n = 3 350) and first failed group (n = 60). Clinical data including age, weight, body mass index (BMI), gestational week, type of pregnancy (singleton/twin), history of delivery, heparin treatment, and conception method [natural conception/assisted reproductive technology (ART)] were collected. Independent sample t-test and Chi-square test were carried out for comparing the two groups, and multi-factorial unconditional Logistic regression analysis was carried out to explore the factors for the failure of NIPT, and receiver operating characteristic curve (ROC) analysis was used to evaluate the diagnosis and predictive effects.@*RESULTS@#Among the 3 410 pregnant women, 3 350 were assigned to the first success NIPT group, and 60 were assigned to the first failed group, and the first-time failure rate was 1.76% (60/3 410). No significant difference was found in age, weight, BMI and method of conception between the two groups (P > 0.05). Compared with first success group, first failed group had lower sampling gestational weeks, lower proportion of women with previous history of delivery, and higher proportion of twin pregnancies and heparin treatment (P < 0.05). Multi-factorial unconditional Logistic regression analysis indicated that sampling gestational week (OR = 0.931, 95%CI: 0.845 ~ 1.026, P < 0.001) and history of heparin use (OR = 8.771, 95%CI: 2.708 ~ 28.409, P < 0.001) are independent factors for first failed NIPT. One-way unconditional Logistic regression analysis for sampling gestational weeks indicated that the regression equation for NIPT screening failure was Logit (P) = -9.867 + 0.319 × sampling gestational week, with the area under the ROC curve being 0.742, a Jordan index of 0.427, and a cutoff value of 16.36 weeks.@*CONCLUSION@#Gestational week and heparin treatment are independent factors for the first failed NIPT. A regression equation has been established and determined the optimal sampling gestational week to be 16.36 weeks, which may provide a reference for the timing of NIPT screening.

Analysis of a twin pregnancy with false negative result for 22q11.2 deletion syndrome by expanded non-invasive prenatal testing / 中华医学遗传学杂志

OBJECTIVE@#To explore the cause for a twin pregnancy with false negative result for 22q11.2 deletion syndrome by expanded non-invasive prenatal testing (NIPT-plus).@*METHODS@#A pregnant woman with twin pregnancy through in-vitro fertilization and negative result of NIPT-plus was selected as the study subject. Amniocentesis was conducted after ultrasonic finding of fetal abnormalities. In addition to conventional G-banded karyotyping, copy number variation sequencing (CNV-Seq) was used to detect chromosomal microdeletion and microduplication. Clinical data of the woman were analyzed to explore the reasons underlying the false negative result.@*RESULTS@#NIPT-plus has yielded a negative result with 11.77 Mb unique reads and 3.05% fetal fraction. Both fetuses had a normal karyotype (46,XY and 46,XX). CNV-seq indicated that one of the fetuses was normal, whilst the other was diagnosed with a 2.58 Mb deletion in the 22q11.2 region.@*CONCLUSION@#The false negative result may be attributed to the combined influence of low fetal fraction, high BMI, twin pregnancy through IVF and a relatively small deletion fragment. Ultrasonography exam following a low-risk result of NIPT-plus should not be neglected.

Association between maternal plasma one-carbon biomarkers during pregnancy and fetal growth in twin pregnancies / 中华妇产科杂志

Objective: To characterize the relationship between the levels of plasma methyl donor and related metabolites (including choline, betaine, methionine, dimethylglycine and homocysteine) and fetal growth in twin pregnancies. Methods: A hospital-based cohort study was used to collect clinical data of 92 pregnant women with twin pregnancies and their fetuses who were admitted to Peking University Third Hospital from March 2017 to January 2018. Fasting blood was collected from the pregnant women with twin pregnancies (median gestational age: 18.9 weeks). The levels of methyl donors and related metabolites in plasma were quantitatively analyzed by high-performance liquid chromatography combined with mass spectrometry. The generalized estimation equation was used to analyze the relationship between maternal plasma methyl donors and related metabolites levels and neonatal outcomes of twins, and the generalized additive mixed model was used to analyze the relationship between maternal plasma methyl donors and related metabolites levels and fetal growth ultrasound indicators. Results: (1) General clinical data: of the 92 women with twin pregnancies, 66 cases (72%) were dichorionic diamniotic (DCDA) twin pregnancies, and 26 cases (28%) were monochorionic diamniotic (MCDA) twin pregnancies. The comparison of the levels of five plasma methyl donors and related metabolites in twin pregnancies with different basic characteristics showed that the median levels of plasma choline and betaine in pregnant women ≥35 years old were higher than those in pregnant women <35 years old, and the differences were statistically significant (all P<0.05). (2) Correlation between plasma methyl donor and related metabolites levels and neonatal growth indicators: after adjusting for confounding factors, plasma homocysteine level in pregnant women with twins was significantly negatively correlated with neonatal birth weight (β=-47.9, 95%CI:-94.3- -1.6; P=0.043). Elevated methionine level was significantly associated with decreased risks of small for gestational age infants (SGA; OR=0.5, 95%CI: 0.3-0.9; P=0.021) and low birth weight infants (OR=0.6, 95%CI: 0.4-0.9; P=0.020). Increased homocysteine level was associated with increased risks of SGA (OR=1.5, 95%CI: 1.0-2.2; P=0.029) and inconsistent growth in twin fetuses (OR=1.9, 95%CI: 1.0-3.7; P=0.049). (3) Correlation between the levels of plasma methyl donors and related metabolites and intrauterine growth indicators of twins pregnancies: for every 1 standard deviation increase in plasma choline level in pregnant women with twin pregnancies, fetal head circumference, abdominal circumference, femoral length and estimated fetal weight in the second trimester increased by 1.9 mm, 2.6 mm, 0.5 mm and 20.1 g, respectively, and biparietal diameter, abdominal circumference and estimated fetal weight increased by 0.7 mm, 3.0 mm and 38.4 g in the third trimester, respectively, and the differences were statistically significant (all P<0.05). (4) Relationship between plasma methyl donor and related metabolites levels in pregnant women with different chorionicity and neonatal birth weight and length: the negative correlation between plasma homocysteine level and neonatal birth weight was mainly found in DCDA twin pregnancy (β=-65.9, 95%CI:-110.6- -21.1; P=0.004). The levels of choline, betaine and dimethylglycine in plasma of MCDA twin pregnancy were significantly correlated with the birth weight and length of newborns (all P<0.05). Conclusion: Homocysteine level is associated with low birth weight in twins, methionine is associated with decreased risk of SGA, and choline is associated with fetal growth in the second and third trimesters of pregnancy.

Non-Invasive Prenatal Testing:Results in 3733 Cases of Twin Pregnancy and Association With Factors Such as Age / 中国医学科学院学报

Objective To explore the clinical significance of non-invasive prenatal testing(NIPT)for fetal chromosomal abnormalities in the cases of twin pregnancy and its relationship with age and other related factors.Methods A total of 3733 women with twin pregnancy of 12-26+6 weeks who voluntarily underwent NIPT in the Ningbo Women and Children's Hospital from January 2018 to December 2022 were selected.The results of NIPT and amniocentesis were compared and all the participants were followed up.The detection rate of chromosomal abnormalities by NIPT was calculated,and its correlations with age,gestational weeks,chorionicity,and pregnancy type were analyzed.Results Among the 3733 cases,71 cases of fetal chromosome abnormality were indicated by NIPT,including 13 cases of trisomy 21,19 cases of trisomy 18,5 cases of trisomy 13,18 cases of sex chromosome abnormality,and 16 cases of chromosome microdeletion/duplication(excluding 21,18,13,and sex chromosomes),among which 34 cases were true positive and 37 cases were false positive.The overall sensitivity,specificity,and positive predictive value(PPV)of NIPT for chromosomal abnormalities in the cases of twin pregnancy were 100%,98.99%,and 47.89%(34/71),respectively.NIPT showed the sensitivity,specificity,and PPV of 100%,99.78%,and 78.38%(29/37)for trisomy 21,18,and 13,100%,99.56%,and 16.67%(3/18)for sex chromosome abnormalities,and 100%,99.62%,and 12.5%(2/16)for chromosome microdeletion/duplication,respectively.In the age group of ≥40 years,the NIPT for chromosomal abnormalities showed the PPV of 66.67%,the sensitivity of 100%,and the misdiagnosis rate of 30%。However,the NIPT for trisomy 21,18,and 13 showed the PPV of 100%,the misdiagnosis rate of 0,and the sensitivity and specificity of 100%.In terms of grouping based on gestational weeks,the NIPT for chromosomal abnormalities showed the highest PPV(51.28%)in the women with twin pregnancy for 14-17+6 weeks,followed by that(50.00%)in the women with twin pregnancy for 22-26+6 weeks;the NIPT for trisomy 21,18,and 13 showed the highest PPV of 94.74% in the gestation group of 14-17+6 weeks,followed by that(83.33%)in the gestation group of 18-21+6 weeks.The rate of dichorionic diamniotic twins was higher in assisted pregnancies than in natural pregnancies,and NIPT showed the same detection efficiency for dichorionic diamniotic twins and monochorionic diamniotic twins and the same detection efficiency for different pregnancy types.Conclusions NIPT has high accuracy in the diagnosis of twin pregnancy and high sensitivity and high specificity for different ages and gestational weeks,especially for trisomy 21,18,and 13.NIPT is suitable for assisted pregnancy and natural pregnancy,and it is of high value in clinical application.However,extensive application needs a large population-based study.

The Use of Mid-Pregnancy Cervical Length to Predict Preterm Birth in Brazilian Asymptomatic Twin Gestations / O uso da medida do colo uterino no segundo trimestre de gestantes brasileiras como preditor de prematuridade na gestação gemelar

Abstract Objective To describe a reference curve for cervical length (CL) in mid-trimester twin gestations using transvaginal ultrasound (TVU) and to investigate whether short CL increases spontaneous preterm birth (sPTB) in asymptomatic twin pregnancies. Methods This was a prospective cohort study performed at 17 outpatient antenatal facilities of Brazil with women at 18 0/7 to 22 6/7 weeks of gestation who participated in a randomized clinical trial screening phase (P5 trial) between July 2015 and March 2019. TVU was performed to provide CL measurement in all screened women. Almost all women with CL ≤ 30 mm received vaginal progesterone 200mg/day and they were also randomized to receive cervical pessary or not. We considered data from the CL distribution among asymptomatic twin pregnancies and analyzed CL and its association with PTB generating receiver operating characteristics (ROC) curves and Kaplan-Meier curves. Results A total of 253 pregnant women with twins were included in the distribution curve. The mean CL was 33.7 mm and median was 35.5mm. The 10th percentile was 17.8mm. We identified a PTB rate of 73.9% (187/253) with 33.6% of sPTB < 37 (85/253) and 15% (38/253) of sPTB < 34 weeks. The best cutoff point to predict sPTB < 37 was 24.15 mm. However, the ROC curve showed a poor performance (0.64). The Kaplan-Meier survival curves identified that only CL values ≤ 20mm were associated to sPTB < 34 weeks. Conclusion A cutoff point of CL ≤ 20 mm can be interesting point to identify short cervix in Brazilian twin pregnancies. However, in Brazilian asymptomatic twin pregnancies, CL does not show a good performance to predict PTB.

Resumo Objetivo Descrever uma curva de referência da medida do colo uterino no Segundo trimestre de gestações gemelares através de ultrassonografia transvaginal (TVU) e investigar a correlação entre a medida do colo uterino (CL) e o parto prematuro espontâneo (sPTB) em pacientes assintomáticas. Métodos Foi realizado uma coorte prospectiva multicêntrica em 17 centros de referência do Brasil com mulheres com gestação gemelar entre 18 0/7 a 22 6/7 semanas de gestação que participaram da primeira fase de um ensaio clínico randomizado (P5 trial) entre Julho/2015 a Março/2019. TVU foi realizada para obter a medida do colo uterino em todas as mulheres. A maioria das mulheres com CL ≤30 mm receberam progesterona por via vaginal 200mg/dia e estas foram randomizadas para receber ou não um pessário cervical. Este estudo considerou dados da medida do colo uterino entre mulheres assintomáticas, desenvolvendo uma curva de referência para gestantes gemelares e sua capacidade de predição do parto prematuro através de curva ROC (receiver operating characteristics) e curvas de sobrevida de Kaplan-Meyer. Resultados O total de 253 gestantes foram incluídos no estudo, A média do CL foi 33.7mm e a mediana 35.5mm. O Percentil 10 do CL foi 17.8mm. A taxa de parto prematuro foi de 73.9% (187/253) com 33.6% de sPTB < 37 (85/253) e 15% (38/253) de sPTB < 34 semanas. O melhor ponto de corte para predizer sPTB < 37 foi 24.15 mm, entretanto a curva ROC demonstrou baixa performance (0.64). A curva de Kaplan-Meier para sPTB identificou que apenas CL ≤ 20 mm estavam associados a sPTB < 34 semanas. Conclusão Colo uterino ≤20 mm pode ser um interessante ponto de corte para identificar colo curto entre gestações gemelares assintomáticas brasileiras. Entretanto, a medida do colo uterino não apresentou boa performance para predizer parto prematuro.

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.

Embarazo Gemelar con Discrepancia Morfologíca. Complejo Malformación y Obstrucción Uretral: diagnóstico prenatal / Twin Pregnancy with Morphologic Discrepancy. Complex Malformation and Urethral Obstruction: prenatal diagnosis

Presentamos un caso de embarazo gemelar, monocorial-bianmiotico con discrepancias morfológicas, diagnóstico de malformación y obstrucción uretral prenatal y diagnóstico postnatal de Síndrome de Prune-Belly. Feto A: Dilatación macroscópica del sistema colector con vejiga grande con paredes finas, hidroureter bilateral , dilatación de la uretra, parenquima renal aumentado de tamaño. Feto B: sin alteraciones morfológicas. Postnatal se observó en feto A abdomen flácido y pastoso, ano imperforado, megavejiga e insuficiencia renal

We present a case of twin pregnancy, monocorial-bi-mixtic with morphological discrepancies, diagnosis of malformation and prenatal urethral obstruction and postnatal diagnosis of Prune-Belly syndrome. Fetus A: Macroscopic dilation of the collecting system with large bladder with fine walls, bilateral hydroureter, dilation of the urethra, renal parenchymal increased in size. Fetus B: without morphological alterations. Postnatal was observed in fetus at flaccid and pasty abdomen, imperforated anus, megavejiga and renal failure.

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.

Preeclampsia de presentación grave asociada a hígado graso agudo del embarazo / Severe preeclampsia associated with acute fatty liver of pregnancy / Pré-eclâmpsia grave associada a fígado gorduroso agudo da gravidez

La preeclampsia se puede asociar a una patología poco frecuente como es el hígado graso agudo del embarazo. Se reporta el caso clínico de una paciente de 35 años, tercigesta, cursando embarazo gemelar que presenta preeclampsia con elementos de gravedad, asociada a hígado graso agudo del embarazo. Se realiza diagnóstico y tratamiento precoz de ambas patologías, presentando buena evolución materno-fetal.

Preeclampsia can be associated with acute fatty liver of pregnancy, a rare disease. This report describes the case of a 35-year-old patient, gravida 3, pregnant with twins, who presented with severe pre-eclampsia associated with acute fatty liver of pregnancy. Early diagnosis and treatment of both pathologies was performed, resulting in good maternal-fetal evolution.

A pré-eclâmpsia pode estar associada a uma patologia rara, como o fígado gorduroso agudo da gravidez. Neste relato, apresentamos uma paciente de 35 anos, terciária, em gestação gemelar, apresentando pré-eclâmpsia grave, associada a esteatose hepática aguda na gestação. É realizado diagnóstico e tratamento precoces de ambas as patologias, apresentando boa evolução materno-fetal.

Gestação e Desenvolvimento Inicial de Gêmeos: Um Estudo a partir de Relatos Maternos / Pregnancy and Early Development of Twins: A Study based on Maternal Reports / Embarazo y Desarrollo inicial de Gemelos: Un Estudio basado en Informes Maternos

As interações sociais iniciais são fundamentais para o desenvolvimento infantil, sendo essencial o papel dos adultos na promoção de práticas que o favoreçam. Tais práticas podem ser influenciadas por aspectos contextuais e pelas emoções, concepções e expectativas parentais sobre seus filhos. No presente estudo, foi considerada a configuração familiar caracterizada pela presença de bebês gêmeos. O objetivo foi conhecer as emoções das mães acerca da gravidez gemelar e analisar as suas concepções e expectativas sobre o desenvolvimento dos gêmeos nos primeiros 24 meses de vida. Participaram deste estudo nove mães de bebês gemelares, que responderam a um questionário sociodemográfico e a uma entrevista semiestruturada. Os resultados revelaram sentimentos maternos ambivalentes relativos à experiência com a gemelaridade desde a gestação; concepções sobre desenvolvimento infantil, fatores que podem influenciá-lo e diferenças entre os gêmeos; e expectativas sobre o desenvolvimento dos bebês. Conclui-se que uma maior compreensão sobre aspectos relacionados à maternidade de gemelares pode auxiliar na criação de redes de apoio socioemocional aos cuidadores e de contextos que favoreçam as interações estabelecidas entre a tríade mãe-bebês.

Initial social interactions are fundamental to child development, and the role of adults in promoting practices that favor them is essential. Such practices can be influenced by contextual aspects and by parental emotions, conceptions and expectations about their children. In the present study, the family configuration characterized by the presence of twin babies was considered. The objective was to get to know the mothers' emotions about twin pregnancies and to analyze their conceptions and expectations about the development of twins in the first 24 months of life. Nine mothers of twin babies participated in this study, who answered a sociodemographic questionnaire and a semi-structured interview. The results revealed ambivalent maternal feelings regarding the experience with twinning since pregnancy; conceptions about child development, factors that can influence it and differences between twins; and expectations about the development of babies. We conclude that a greater understanding of aspects related to twin maternity can help in the creation of social and emotional support networks for caregivers and contexts that favor the interactions established between the mother-babies triad.

Las interacciones sociales iniciales son fundamentales para el desarrollo infantil, siendo fundamental el rol de los adultos en la promoción de prácticas que los favorezcan. Dichas prácticas pueden estar influenciadas por aspectos contextuales y por emociones, concepciones y expectativas de los padres sobre sus hijos. En el presente estudio se consideró la configuración familiar caracterizada por la presencia de bebés gemelos. El objetivo fue conocer las emociones de las madres sobre los embarazos gemelares y analizar sus concepciones y expectativas sobre el desarrollo de los gemelos en los primeros 24 meses de vida. En este estudio participaron nueve madres de gemelos, quienes respondieron un cuestionario sociodemográfico y una entrevista semiestructurada. Los resultados revelaron sentimientos maternos ambivalentes con respecto a la experiencia del hermanamiento desde el embarazo; concepciones sobre el desarrollo infantil, factores que pueden influir en él y diferencias entre gemelos; y expectativas sobre el desarrollo de los bebés. Concluimos que una mayor comprensión de los aspectos relacionados con la maternidad gemelar puede ayudar en la creación de redes de apoyo social y emocional a los cuidadores y contextos que favorezcan las interacciones que se establecen entre la tríada madre-bebé.

¿La progesterona natural micronizada previene el trabajo de parto pretérmino?: Revisión sistemática de literatura / Does Natural Micronized Progesterone Prevent Preterm Labor?: Systematic Literature Review / A progesterona natural micronizada previne o trabalho de parto prematuro?: Revisão sistemática da literatura

Introducción. La progesterona es una hormona que favorece el mantenimiento del embarazo, es la protagonista de la fisiopatología del trabajo de parto pretérmino. De esta manera, se propone realizar una revisión sistemática que permita demostrar la utilidad de la progesterona natural micronizada en la mitigación de los efectos deletéreos del trabajo de parto pretérmino. Metodología. Revisión sistemática en la que se utilizaron los términos "MeSH" y "No ­ MeSH". Se empleó el programa "Publish or Perish" y bases de datos como: Medline, PubMed, Embase, Clinical Key, Cochrane Library, Scopus y Google Scholar. Se incluyeron artículos de revisión, meta-análisis, artículos originales (publicaciones preliminares o completas), resúmenes de congresos, seminarios publicados, libros de texto, protocolos hospitalarios regionales y consensos nacionales, en donde cada autor evaluó individualmente cada artículo y aplicó la herramienta CASPE. Resultados. En la literatura no es posible encontrar pautas concisas internacionales sobre el uso de la progesterona micronizada frente a la amenaza de trabajo de parto pretérmino (TPP). En general, para la mitigación del trabajo de parto, según lo analizado por los autores, se recomienda usar progesterona natural micronizada en cápsulas de 100 a 400 mg/día vía oral o 100 a 200 mg cada 12 a 24 horas vía vaginal. Desde la semana 16 hasta la semana 36 de gestación por vía oral y desde la semana 24 a 34 de gestación por vía vaginal. Discusión. El uso de la progesterona micronizada ha demostrado mitigar complicaciones posteriores al trabajo de parto pretérmino, sin embargo, no hay consenso sobre la dosificación y las vías de administración. Sumado a lo anterior, los estudios analizados pueden contener sesgos, por lo que se deja a elección del clínico el uso este medicamento. Conclusiones. La progesterona natural micronizada podría ser empleada para mitigar el trabajo de parto pretérmino según los artículos analizados por los autores a lo largo de la revisión. Sin embargo, se necesitan más estudios para legitimar dicha hipótesis.

Introduction. Progesterone is a hormone that favors maintaining pregnancy. It is the protagonist of the physiopathology of preterm labor. In this sense, a systematic review is proposed to demonstrate the usefulness of natural micronized progesterone in mitigating the harmful effects of preterm labor. Methodology. A systematic review in which the terms "MeSH" and "No ­ MeSH" were used. The "Publish or Perish" program was used, as well as databases, such as: Medline, PubMed, Embase, Clinical Key, Cochrane Library, Scopus, and Google Scholar. Review and meta-analysis articles, original articles (preliminary or complete publications), congress summaries, published seminars, textbooks, regional hospital protocols and national consensuses were included, in which each author individually assessed each article and applied the CASPE tool. Results. It was not possible to find concise international guidelines on using micronized progesterone for the threat of preterm labor (PTL) in literature. According to what the authors analyzed, for the mitigation of labor it is generally recommended the use of natural micronized progesterone in 100 to 400 mg/day capsules orally or 100 to 200 mg every 12 to 24 hours through the vagina. From week 16 to week 36 of pregnancy orally and from week 24 to 34 through the vagina. Discussion. Using micronized progesterone has demonstrated mitigating complications subsequent to preterm labor. However, there is no consensus on dosage and routes of administration. Added to the above, the analyzed studies may contain biases, reason why using this medication is left to the physician's discretion. Conclusions. Natural micronized progesterone can be used to mitigate preterm labor according to the articles the authors analyzed throughout the review. However, more studies are needed to validate this hypothesis.

Introdução. A progesterona é um hormônio que favorece a manutenção da gravidez, é a protagonista da fisiopatologia do parto prematuro. Dessa forma, propõe-se a realização de uma revisão sistemática que permita demonstrar a utilidade da progesterona natural micronizada na mitigação dos efeitos deletérios do trabalho de parto prematuro. Metodologia. Revisão sistemática em que foram utilizados os termos "MeSH" e "Não­MeSH". Foram utilizados o programa "Publish or Perish" e bases de dados como: Medline, PubMed, Embase, Clinical Key, Cochrane Library, Scopus e Google Scholar. Foram incluídos artigos de revisão, meta-análises, artigos originais (publicações preliminares ou completas), resumos de congressos, seminários publicados, livros didáticos, protocolos hospitalares regionais e consensos nacionais, onde cada autor avaliou individualmente cada artigo e aplicou a ferramenta CASPE. Resultados. Não é possível encontrar na literatura diretrizes internacionais concisas sobre o uso de progesterona micronizada diante da ameaça de trabalho de parto prematuro (TPP). Em geral, para a mitigação do trabalho de parto, conforme analisado pelos autores, recomenda-se o uso de progesterona natural micronizada em cápsulas de 100 a 400mg/dia por via oral ou 100 a 200mg a cada 12 a 24 horas por via vaginal. Da 16ª à 36ª semana de gestação por via oral e da 24ª à 34ª semana de gestação por via vaginal. Discussão. O uso de progesterona micronizada demonstrou mitigar as complicações após o trabalho de parto prematuro, no entanto, não há consenso sobre a dosagem e as vias de administração. Além do exposto, os estudos analisados podem conter vieses, pelo que cabe ao médico escolher o uso deste medicamento. Conclusões. A progesterona natural micronizada poderia ser utilizada para mitigar o trabalho de parto prematuro de acordo com os artigos analisados pelos autores ao longo da revisão. No entanto, mais estudos são necessários para legitimar essa hipótese.