常见病因如下：1.孕母因素①缺氧性疾病：如呼吸衰竭、青紫型先天性心脏病、严重贫血及CO中毒等；②障碍胎盘循环的疾病：如充血性心力衰竭、妊娠高血压综合征、慢性肾炎、失血、休克、糖尿病和感染性疾病等；③其他：孕母吸毒、吸烟或被动吸烟、孕母年龄≥35岁或＜16岁、多胎妊娠等，其胎儿窒息发生率增高。
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