Luterkort M, Polberger S, Weldner B M, Persson P H, Bjerre I
Acta Obstet Gynecol Scand. 1986;65(2):157-60. doi: 10.3109/00016348609158372.
225 fetuses with ultrasonically determined gestational age were shown by ultrasound to be in breech presentation in the 33rd gestational week. The biparietal diameter (BPD) and the mean of two perpendicular abdominal diameters (AD) were measured ultrasonically in gestational weeks 33, 35, and 38. Based on these measurements, fetal weight was estimated and compared with weight, length, and head circumference at birth and at 18 months of age. 42% of the fetuses were born in breech presentation (breech group) and 58% in vertex presentation (vertex group). The mean birth weight corrected for gestational age was 4.9% lower in the breech group than in the vertex group, which corresponds to the lower intra-uterine values of BPD and AD found in the breech group. The weight differences at birth still persisted at 18 months of age. There were no differences between the groups regarding head circumference or length, either at birth or at 18 months of age.
通过超声检查确定胎龄的225例胎儿，在孕33周时经超声显示为臀位。在孕33、35和38周时超声测量双顶径（BPD）和两条相互垂直的腹径（AD）的平均值。基于这些测量值，估算胎儿体重，并与出生时及18个月龄时的体重、身长和头围进行比较。42%的胎儿为臀位出生（臀位组），58%为头位出生（头位组）。校正胎龄后的平均出生体重，臀位组比头位组低4.9%，这与臀位组较低的子宫内BPD和AD值相符。出生时的体重差异在18个月龄时仍然存在。两组在出生时及18个月龄时的头围或身长方面均无差异。
