Watson W J, Valea F A, Seeds J W
Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill 27599-7570.
Am J Perinatol. 1991 Sep;8(5):342-4. doi: 10.1055/s-2007-999410.
Ninety-four twin gestations had serial ultrasound examinations for evaluation of fetal growth, with special attention to prediction of weight discordance and chorionicity. Fetal weight estimations were made a mean of 3.2 days before birth and then compared to actual birthweights. The average error in intertwin discordance prediction was 1 +/- 9%. In 56 patients ultrasonic detection of membrane thickness was compared with placental pathologic conditions. If a membrane was seen between twins, it was confirmed by placental pathologic study in all cases. No membrane was seen in four twin pairs, but only one of these actually had monochorionic monoamniotic membranes. The three cases with false-positive diagnoses of monoamniotic twin gestation were initially seen late in pregnancy. If clinical decisions in twin gestations are based on ultrasound determination of discordance and chorionicity, the level of accuracy demonstrated by these data must be considered.
94例双胎妊娠接受了系列超声检查以评估胎儿生长情况，特别关注体重不一致性和绒毛膜性的预测。胎儿体重估计在出生前平均3.2天进行，然后与实际出生体重进行比较。双胎间不一致性预测的平均误差为1±9%。在56例患者中，将超声检测的胎膜厚度与胎盘病理情况进行了比较。如果在双胎之间看到胎膜，则在所有病例中均经胎盘病理研究证实。在4对双胎中未看到胎膜，但其中只有1对实际为单绒毛膜单羊膜囊双胎。3例单羊膜囊双胎妊娠诊断为假阳性的病例最初是在妊娠晚期发现的。如果双胎妊娠的临床决策基于超声确定的不一致性和绒毛膜性，则必须考虑这些数据所显示的准确性水平。
