Background: The worldwide prevalence of FGR is about 13% and can lead to various adverse perinatal outcomes, including preterm birth, stillbirth, and neonatal mortality. Hypoxia-Inducible Factor-1 (HIF-1) is an important regulator of oxygen homeostasis in humans and is crucial for placental development. The aim of this study is to determine the pattern of HIF-1A expression in placenta, and to correlate its association with preeclampsia, fetal growth restriction and adverse perinatal outcomes. Methods: This study comprised a total of 158 cases with 42 cases of mother having babies with fetal growth restriction (FGR), 39 cases of mother with preeclampsia (PE), 35 cases of mother with preeclampsia and fetal growth restriction and 42 controls. The expression of HIF-1A was evaluated in various placental cell types, including cytotrophoblasts, syncytiotrophoblasts, fetal endothelial cells, maternal endothelial cells, and decidual cells. Results: The expression of HIF-1A in placental decidual cells of mother with FGR (21/42, 50%, p < 0.0001), PE (25/39, 64.1%, p < 0.0001) and PE with FGR (12/35, 34.3%, p < 0.0001) were significantly increased compared to controls (1/42). Intriguingly, HIF-1A expression was significantly reduced in the placental cytotrophoblasts and syncytiotrophoblasts of mother with PE and FGR (2/35, 5.7%) compared to PE alone (11/39, 28.2%) (p = 0.0142). Conclusions: We found that increased HIF-1A expression in the nuclei of decidual cells was observed in the mothers of babies with FGR, both with and without PE. While HIF-1A expression in the cytotrophoblasts and syncytiotrophoblasts was significantly reduced between mothers with PE and mothers with PE and FGR. This suggests HIF-1A expression might play a role in the pathogenesis of FGR.

Background: Connexins (Cx) 43 and 40 play a role in leukocytes recruitment in acute inflammation. They are expressed in the endothelial cells. They are also found in the placenta and involved in the placenta development. Acute chorioamnionitis is associated with an increased risk of adverse perinatal outcomes. The aim of this study was to determine the expressions of Cx43 and Cx40 in the placenta of mothers with acute chorioamnionitis, and to correlate their association with the severity of chorioamnionitis and adverse perinatal outcomes. Methods: This study comprised a total of 81 cases, consisting of 39 placenta samples of mothers with acute chorioamnionitis and 42 non-acute chorioamnionitis controls. Cx43 and Cx40 immunohistochemistry were performed on all cases and their expressions were evaluated on cytotrophoblasts, syncytiotrophoblasts, chorionic villi endothelial cells, stem villi endothelial cells, maternal endothelial cells and decidua of the placenta. Results: Primigravida has a significantly higher risk of developing acute chorioamnionitis (p < 0.001). Neonates of mothers with a higher stage of fetal inflammatory response was significantly associated with lung complications (p = 0.041) compared to neonates of mothers with a lower stage. The expression of Cx40 was significantly higher in fetal and maternal vascular endothelial cells in acute chorioamnionitis (p < 0.001 and p = 0.037, respectively) compared to controls. Notably, Cx43 was not expressed in most of the types of cells in the placenta, except for decidua. Both Cx43 and Cx40 expressions did not have correlation with the severity of acute chorioamnionitis and adverse perinatal outcomes. Conclusion: Cx40 was overexpressed in the fetal and maternal vascular endothelial cells in the placenta of mothers with acute chorioamnionitis, and it may have a role in the development of inflammation in placenta.