Obstet Gynecol. 2013 Apr;121(4):908-910. doi: 10.1097/01.AOG.0000428648.75548.00.
The neonatal risks of late preterm (34 0/7-36 6/7 weeks of gestation) and early-term (37 0/7-38 6/7 weeks of gestation) births are well established. However, there are a number of maternal, fetal, and placental complications in which either a late-preterm or early-term delivery is warranted. The timing of delivery in such cases must balance the maternal and newborn risks of late-preterm and early-term delivery with the risks of further continuation of pregnancy. Decisions regarding timing of delivery must be individualized. Amniocentesis for the determination of fetal lung maturity in well-dated pregnancies generally should not be used to guide the timing of delivery.
晚期早产儿（34 0/7-36 6/7 孕周）和早期足月产儿（37 0/7-38 6/7 孕周）的新生儿风险已得到充分证实。然而，在许多情况下，无论是晚期早产儿还是早期足月产儿的分娩都是必要的，这些情况涉及到母亲、胎儿和胎盘的并发症。在这种情况下，分娩时机必须平衡晚期早产儿和早期足月产儿的母婴风险与进一步继续妊娠的风险。分娩时机的决策必须个体化。对于有明确预产期的孕妇，羊膜腔穿刺术以确定胎儿肺成熟度通常不应用于指导分娩时机。
