reactive oxygen species and angiogenic factor (vasculo-endothelial growth factor and placenta growth factor) in placenta accreta spectrum

Placenta accreta spectrum (pas) is an abnormal condition characterized by the placenta penetrating the myometrial wall and uterine serosa, accompanied by hyper-vascularization. major risk factors for pas include a history of cesarean sections, curettage, and in vitro fertilization. these procedures can lead to endometrial abnormalities that contribute to excessive trophoblast invasion, marking the early stages of pas. trophoblast invasion plays a crucial role in initiating growth, vasculogenesis, and angiogenesis. disruptions in placentation during early pregnancy can arise from imbalanced angiogenesis and vasculogenesis. reactive oxygen species (ros), highly reactive molecules produced through the reduction of oxygen, are involved in cellular signaling pathways. during early pregnancy, low oxygen concentrations, influenced by ros, and angiogenic factors such as vascular endothelial growth factor (vegf) and placental growth factor (plgf) are essential for trophoblast invasion. furthermore, ros can affect bleeding due to their role in hemostasis; excess ros may disrupt normal hemostatic function and contribute to abnormal bleeding.