Analysis Of Placental Pathology And The Expression Of HIF-1α And VEGF In Placentas With Meconium-stained Amniotic Fluid

Objective:Analyse the significance of placental pathological change and the expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in placentas with Ⅱ-Ⅲ degree meconium-stained amniotic fluid, to discuss the connection with fetal distress.Methods:Seventy-eight puerperants who have had delivery in People’s center hospital of Tengzhou city from January,2012to May,2012were divided into two groups, the meconium-stained group and the normal group. In the meconium-stained group concluding thirty-nine puerperants diagnosed as fetal distress and with Ⅱ-Ⅲ degree meconium-stained amniotic fluid, thirteen puerperants underwent vaginal delivery and twenty-six puerperants underwent cesarean delivery. The normal group also concluded thirty-nine puerperants delivered during the same period. They were compared with the meconium-stained group according to gestational weeks and delivery methods using pair analysis. Cesarean section indications of the normal group were uterine scar or breech presentation. Both two groups have undergone normal pregnant process, had no cord around neck or body, and had not used corticosteroid drugs. After delivery of the fetus, umbilical artery blood were extracted, analyzed for blood gas analysis and compared of the variation of pH value by t-test. Neonatal Apgar score at1min was also been compared conventionally by t-test. Pathological changes of placental tissues were observed under microscope, and HIF-1a and VEGF expression in placentas were detected by immunohistochemistry. Then analyze data of two groups statistically by χ2-test.Results:For umbilical cord arterial blood gas analysis, mean pH of the meconium-stained group was lower than that of the normal group, but the difference did not have statistical significance (P>0.05). For neonatal Apgar score at1min,3cases of neonatal asphyxia occurred in the meconium-stained group, of which2cases pale asphyxia and1case neonatal death, while only1cases of blue asphyxia occurred in the normal group. Compared the two groups, a decreasing tendency existed in1min Apgar score, but the difference had no statistical significance (P>0.05). The main placental pathologic changes of the meconium-stained group were histomorphological changes and placental inflammatory manifestations including of inflammatory cell infiltration, villous edema, fibrinoid necrosis. In the meconium-stained group, there were19cases of inflammatory cell infiltration,15cases of villous edema,10cases of fibrinoid necrosis. While in the normal group the according data were7cases,5cases,4cases. Compared with the normal group, placentas in the meconium-stained group were easier to produce pathological changes. The difference was statistically significant (P<0.05). HIF-1α positive expression in placentas of the meconium-stained group was significantly higher than that of the normal group, while VEGF positive expression in placentas of the meconium-stained group was lower than that of the normal group, and the difference was statistically significant (P<0.05).Conclusion:Compared the meconium-stained group with the normal group, differences of placental pathologic changes and HIF-1α, VEGF expression in placentas were statistically significant. Placental pathologic changes and HIF-1α, VEGF factor abnormal expressions in placenta have certain consistency with clinical diagnosis of fetal distress. That is, they may be one of the causes of intrauterine fetal distress.