Molecular Mechanisms Underlying Twin-to-Twin Transfusion Syndrome

Twin-to-twin transfusion syndrome is a unique disease and a serious complication occurring in 10–15% of monochorionic multiple pregnancies with various placental complications, including hypoxia, anemia, increased oxidative stress, and ischemia-reperfusion injury. Fetoscopic laser photocoagulation, a minimally invasive surgical procedure, seals the placental vascular anastomoses between twins and dramatically improves the survival rates in twin-to-twin transfusion syndrome. However, fetal demise still occurs, suggesting the presence of causes other than placental vascular anastomoses. Placental insufficiency is considered as the main cause of fetal demise in such cases; however, little is known about its underlying molecular mechanisms. Indeed, the further association of the pathogenic mechanisms involved in twin-to-twin transfusion syndrome placenta with several molecules and pathways, such as vascular endothelial growth factor and the renin–angiotensin system, makes it difficult to understand the underlying pathological conditions. Currently, there are no effective strategies focusing on these mechanisms in clinical practice. Certain types of cell death due to oxidative stress might be occurring in the placenta, and elucidation of the molecular mechanism underlying this cell death can help manage and prevent it. This review reports on the molecular mechanisms underlying the development of twin-to-twin transfusion syndrome for effective management and prevention of fetal demise after fetoscopic laser photocoagulation

Longitudinal hematological change in uncomplicated twin pregnancies: The white blood cell count decreases through pregnancy after the first trimester

Objective: Longitudinal hematological changes throughout twin pregnancies have not been reported. This study aimed to reveal longitudinal changes in hematological indices in twin pregnancies. Materials and methods: We conducted a retrospective chart review of hematological changes in uncomplicated twin pregnancies delivered at ≥37 weeks of gestation between 2010 and 2013 and randomly selected uncomplicated singletons during the same period. A complete blood count and hemogram were performed as blood examinations in the first trimester (9–13 weeks), late second trimester (22–27 weeks), mid-third trimester (33–35 weeks, only in twin pregnancies), and late third trimester (36–38 weeks). We evaluated inter-trimester differences in hematological indices and compared the values between twin and singleton pregnancies in each trimester. Results: The final analysis group included 60 twin pregnancies and 63 singleton pregnancies. The white blood cell (WBC) count in twin pregnancies decreased throughout the pregnancy after the first trimester and became significantly lower than that in singletons in the late third trimester. The WBC count showed only a slight decrease in the third trimester in singleton pregnancies, whereas it showed a marked decrease throughout the pregnancy in twin pregnancies. The marked decrease in the total WBC count in twin pregnancies is mainly due to a decrease in neutrophils. The red blood cell count and hemoglobin and hematocrit values in twin pregnancies showed more marked decreases in the second trimester than in singletons. No decrease was observed after the second trimester of pregnancy. The platelet count decreased in the third trimester of twin pregnancies. Conclusion: We clarified the longitudinal hematological changes in twin pregnancies that showed augmentation of or differed from those of singleton pregnancies. It should be specifically mentioned that the WBC count markedly decreased through pregnancy after the first trimester, which is a characteristic change in twin pregnancies

Congenital high airway obstruction syndrome (CHAOS) combined with esophageal atresia, tracheoesophageal fistula and duodenal atresia

Congenital high airway obstruction syndrome (CHAOS) is a rare congenital anomaly and the most common etiology is laryngeal atresia. Recently, an increasing number of cases have survived due to prenatal diagnosis and pre- and peri-natal care including ex-utero intrapartum treatment (EXIT). More than 100 cases of CHAOS have been reported, and about half of them were complicated with associated anomalies. Here we report a very rare case of prenatally diagnosed CHAOS (laryngeal atresia) complicated with esophageal atresia, tracheoesophageal fistula (TEF) and duodenal atresia, and the patient was saved by EXIT. This combination of anomalies resulted in a very confusing prenatal diagnosis with unique imaging feature of the fetus

A poor long-term neurological prognosis is associated with abnormal cord insertion in severe growth-restricted fetuses

Our data showed that growth restricted fetus in 3th percentile with abnormal cord insertion was higher risk factor for adverse neurological outcomes such as cerebral palsy or developmental disorder.<br