前置胎盘

证据评分

证据 A Fetal mortality: there is good-quality evidence that, between 24 and 34 weeks' gestation, antenatal corticosteroids are effective in reducing perinatal mortality. Fetal morbidity: there is good-quality evidence that antenatal corticosteroids are effective in reducing respiratory distress syndrome, intraventricular haemorrhage, necrotising enterocolitis, and neonatal infections in the first 48 hours of life. 系统评价或者受试者＞200名的随机对照临床试验（RCT）。

Fetal mortality: there is good-quality evidence that, between 24 and 34 weeks' gestation, antenatal corticosteroids are effective in reducing perinatal mortality. Fetal morbidity: there is good-quality evidence that antenatal corticosteroids are effective in reducing respiratory distress syndrome, intraventricular haemorrhage, necrotising enterocolitis, and neonatal infections in the first 48 hours of life.

证据 C Elective compared with selective caesarean delivery: it is not known whether elective caesarean delivery is more effective than selective caesarian section at improving Apgar scores at 5 minutes, at reducing the need for neonatal intubation, or at reducing intracranial haemorrhage in preterm infants. 系统评价或者受试者＞200名的随机对照临床试验（RCT）。

Elective compared with selective caesarean delivery: it is not known whether elective caesarean delivery is more effective than selective caesarian section at improving Apgar scores at 5 minutes, at reducing the need for neonatal intubation, or at reducing intracranial haemorrhage in preterm infants.