Kurjak A, Barsić B
Acta Obstet Gynecol Scand. 1977;56(3):161-5. doi: 10.3109/00016347709162113.
Over a period of two years, 7 137 localisations of placenta were performed. In 67 patients on the first examination it was found that the lower margin of placenta reached the internal os of the uterus. All these patients were followed up by examinations every two or four weeks. In 63 of the 67 patients, placental migration was found involving a change in the level of the lower placental edge from the cervix towards the fundus. The change in this position varied from 3 to 9 cm. All four cases where the placenta extended from anterior to posterior wall ended as placenta praevia. Ultrasonic proof of placental migration shows the necessity for ultrasonic examination shortly before the birth, as only then is the final diagnosis of placenta praevia possible.
在两年的时间里，共进行了7137次胎盘定位检查。在67例患者的首次检查中，发现胎盘下缘达到子宫内口。所有这些患者每两到四周接受一次检查随访。67例患者中有63例出现胎盘迁移，表现为胎盘下缘位置从宫颈向宫底发生改变。该位置变化范围为3至9厘米。胎盘从前壁延伸至后壁的4例均诊断为前置胎盘。胎盘迁移的超声证据表明，在临产前不久进行超声检查很有必要，因为只有那时才有可能对前置胎盘做出最终诊断。
