超声测量胎儿腹围预测新生儿出生体重的研究

目的探讨超声测量胎儿腹围在预测新生儿出生体重和诊断巨大儿中的价值。方法在孕妇分娩前1周超声测量胎儿腹围,追踪胎儿的出生体重,分析胎儿腹围与出生体重的关系。结果(1)共检测1475例单胎孕妇胎儿,胎儿腹围与出生体重呈直线正相关关系,r为0.85(P<0.01)。(2)胎儿腹围<34cm者中无一例巨大儿;胎儿腹围<35cm有1007例,99.7%的新生儿平均出生体重<4000g;胎儿腹围在35～35.9cm有206例,新生儿平均出生体重为(3691±277)g,其中14.6%(30例)的新生儿出生体重≥4000g;胎儿腹围在36～36.9cm有149例,其中51.0%(76例)的新生儿出生体重≥4000g,新生儿平均出生体重为(3957±256)g;胎儿腹围在37～37.9cm有64例,其中84.4%(54例)的新生儿出生体重≥4000g,平均出生体重(4205±250)g;胎儿腹围≥38cm有44例,新生儿平均出生体重≥4000g者为100%(44例),平均出生体重为(4489±267)g。(3)1475例中有811例孕妇行剖宫产术(55.0%),新生儿出生体重为4000～4500g者,剖宫产率为71.4%(125/175),出生体重≥4500g者,剖宫产率为93.8%(30/32),均显著高于新生儿出生体重<4000g的剖宫产率(P<0.01)。结论超声测量胎儿腹围可以预测新生儿出生体重。胎儿腹围与胎儿体重呈高度直线正相关。胎儿腹围<35cm提示发生巨大儿的可能性极低;≥37cm提示巨大儿的可能性大。

Relationship between fetal abdominal circumference and birth weight: clinical findings in 1475 pregnancies

OBJECTIVE: To determine the reliability of the fetal abdominal circumference (FAC) measured by ultrasound as a predictor of birth weight. METHODS: FAC was measured by ultrasound within 0-7 days of delivery and the birth weight were followed in 1475 pregnant women. Statistics analysis was carried out to determine the relationship between FAC and birth weight. RESULTS: Ultrasound measurement of FAC had a linear relation with birth weight, and the correlation coefficient was 0.85. Among the fetuses with FAC < 34 cm, no newborn had a weight more than 4000 g; the macrosomia rate was only 1.1% when FAC was between 34-34.9 cm. Among the fetuses with FAC between 35-35.9 cm, the average birth weight was (3691 +/- 277) g, the macrosomia rate was 14.6%; when FAC was between 36-36.9 cm, the average birth weight was (3957 +/- 256) g, the macrosomia rate was 51.0%. The macrosomia rate was 84.4% with FAC between 37-37.9 cm. When FAC > or = 38 cm the macrosomia rate was 100%. The cesarean section rate for the newborn weighing between 4000-4500 g was 71.4%, and for the fetuses weighing > or = 4500 g the cesarean section rate was 93.8%, which was significantly higher than that of fetuses weighing less than 4000 g. Only one baby who weighed 4350 g had shoulder dystocia with Erb's palsy and clavicle fracture, but recovered 2 months later. CONCLUSIONS: FAC measured by ultrasound can help to evaluate the birth weight. It is useful in screening macrosomia and avoiding shoulder dystocia.