Malvasi A, Tinelli A, Barbera A, Eggebø T M, Mynbaev O A, Bochicchio M, Pacella E, Di Renzo G C
Santa Maria Hospital, Gynecology and Obstetric , Bari , Italy .
J Matern Fetal Neonatal Med. 2014 Mar;27(5):520-6. doi: 10.3109/14767058.2013.825598. Epub 2013 Sep 13.
The occiput posterior (OP) position is one of the most frequent malposition during labor. During the first stage of labor, the fetal head may stay in the OP position in 30% of the cases, but of these only 5-7% remains as such at time of delivery. The diagnosis of OP position in the second stage of labor is made difficult by the presence of the caput succedaneum or scalp hair, both of which may give some problem in the identification of fetal head sutures and fontanels and their location in relationship to maternal pelvic landmarks. The capability of diagnosing a fetus in OP position by digital examination has been extremely inaccurate, whereas an ultrasound approach, transabdominal, transperineal and transvaginal, has clearly shown its superior diagnostic accuracy. This is true not only for diagnosis of malpositions, detected in both first and second stage of labor, but also in cases of marked asynclitism.
枕后位（OP）是分娩过程中最常见的胎位异常之一。在第一产程中，30%的病例胎儿头部可能处于枕后位，但其中只有5-7%在分娩时仍保持该胎位。由于存在头皮水肿或头皮毛发，第二产程中枕后位的诊断变得困难，这两者都会给识别胎儿头部缝线和囟门及其相对于母体骨盆标志的位置带来一些问题。通过指诊诊断枕后位胎儿的能力极不准确，而经腹、经会阴和经阴道的超声检查方法已清楚地显示出其更高的诊断准确性。这不仅适用于在第一和第二产程中检测到的胎位异常诊断，也适用于明显斜径不均的情况。
