Effectiveness of aortic balloon occlusion in reducing blood loss during cesarean section in placenta accreta spectrum disorders: a study protocol for a randomized controlled trial - Bapayeva, Gauri; Aimagambetova, Gulzhanat; Kadroldinova, Nazira; Zemlyanskiy, Viktor; Kassymbek, Kuat; Terzic, Milan (Frontiers in Medicine, 2025)