初產(chǎn)婦,G2P0,孕35周,行外倒轉(zhuǎn)術(shù)后,腹痛,伴少量陰道流血,查血壓17.3/12kPa(130/90mmHg),水腫(+),腹部壓痛不明顯,胎心160次/分,最可能的診斷是()