严重性产后出血是指()

严重性产后出血是指（)

A、胎儿娩出后24h出血量≥800ml

B、胎儿娩出后24h出血量≥1000ml

C、胎儿娩出后48h出血量≥1000ml

D、胎儿娩出后48h出血量≥1200ml

E、胎儿娩出后48h出血量≥1500ml