Papp Zoltán
I. Department of Obstetrics and Gynecology, Semmelweis University, Budapest, Hungary.
J Perinat Med. 2003;31(5):415-9. doi: 10.1515/JPM.2003.064.
Breech presentation is the most common malpresentation, with about 3-4% of singleton fetuses presenting breech at delivery. Management of breech presentation has been a contentious issue with a lowering threshold for cesarean section in recent years. Perinatal mortality and morbidity are estimated to be three times that of comparable infants with vertex presentation. Breech presentation is commonly associated with certain adverse maternal and fetal factors which inherently give rise to increased perinatal morbidity and mortality. At present, most obstetricians favor cesarean delivery for uncomplicated pre-term breech. Controlled prospective studies have shown that the outcome of breech fetuses weighing more than 1500 g was not dependent on the mode of delivery. A more recent review from the Cochrane database by Grant does not justify a policy of elective cesarean section for pre-term breech. Vaginal delivery is preferred if the following criteria are met: frank breech only, estimated fetal weight of 2500-3500 g, adequate pelvimetry without hyperextended head, normal progression of labor, no evidence of fetal hypoxia under continuous fetal monitoring, and maternal weight under 90 kg. Vaginal delivery of frank breech at term may be just as safe as cesarean section when careful selection criteria are used. If these criteria are not fulfilled, or fetal monitoring cannot be performed, cesarean section is advisable.
臀位是最常见的胎位异常，约3-4%的单胎胎儿在分娩时为臀位。近年来，臀位的处理一直是一个有争议的问题，剖宫产的阈值有所降低。据估计，围产期死亡率和发病率是头位分娩的同类婴儿的三倍。臀位通常与某些不利的母体和胎儿因素相关，这些因素本身就会导致围产期发病率和死亡率增加。目前，大多数产科医生倾向于对无并发症的早产臀位进行剖宫产。对照前瞻性研究表明，体重超过1500克的臀位胎儿的结局并不取决于分娩方式。格兰特对Cochrane数据库的最新综述并不支持对早产臀位进行选择性剖宫产的政策。如果符合以下标准，首选阴道分娩：仅为单臀先露、估计胎儿体重2500-3500克、骨盆测量正常且无头部过度伸展、产程进展正常、连续胎儿监护下无胎儿缺氧证据、产妇体重低于90公斤。当使用仔细的选择标准时，足月单臀先露的阴道分娩可能与剖宫产一样安全。如果这些标准未得到满足，或无法进行胎儿监护，则建议剖宫产。
