Kagan K O, Gazzoni A, Sepulveda-Gonzalez G, Sotiriadis A, Nicolaides K H
Harris Birthright Research Centre for Fetal Medicine, King's College Hospital Medical School, London, UK.
Ultrasound Obstet Gynecol. 2007 May;29(5):527-32. doi: 10.1002/uog.4006.
To examine in monochorionic pregnancies the possible value of intertwin discordance in nuchal translucency (NT) thickness in the prediction of early fetal death or severe twin-twin transfusion syndrome (TTTS).
In 512 monochorionic twin pregnancies NT was measured at 11 to 13 + 6 weeks' gestation and regression analysis was used to determine the significance of the association between the intertwin discordance in NT and subsequent early fetal death or development of severe TTTS requiring endoscopic laser surgery.
In 412 (80.5%) pregnancies there was a normal outcome, in 58 (11.3%) there was severe TTTS requiring endoscopic laser surgery at 18-24 weeks, in 19 (3.7%) there was death of one or both fetuses at 13-18 weeks and in 23 (4.5%) there was fetal death at 21-38 weeks. In the four outcome groups the median discordance in NT was 11%, 22%, 35% and 7%, respectively. Significant prediction of early fetal death and severe TTTS was provided by the discordance in fetal NT, which was not significantly improved by including the discordance in crown-rump length. If the discordance in NT was 20% or more, the false positive rate was 20%, the detection rate of early fetal death was 63% and the detection rate of severe TTTS was 52%.
Discordance in NT of 20% or more is found in about 25% of monochorionic twins and in this group the risk of early fetal death or development of severe TTTS is more than 30%. If the discordance is less than 20% the risk of complications is less than 10%.
探讨单绒毛膜双胎妊娠中双胎间颈部半透明层（NT）厚度差异在预测早期胎儿死亡或严重双胎输血综合征（TTTS）方面的潜在价值。
对512例单绒毛膜双胎妊娠在孕11至13⁺⁶周时测量NT，并采用回归分析确定NT双胎间差异与随后的早期胎儿死亡或发展为需要内镜激光手术的严重TTTS之间关联的显著性。
412例（80.5%）妊娠结局正常，58例（11.3%）在18至24周时发生严重TTTS需要内镜激光手术，19例（3.7%）在13至18周时一个或两个胎儿死亡，23例（4.5%）在21至38周时发生胎儿死亡。在四个结局组中，NT的中位数差异分别为11%、22%、35%和7%。胎儿NT差异对早期胎儿死亡和严重TTTS有显著预测作用，纳入顶臀长差异后并无显著改善。如果NT差异为20%或更大，假阳性率为20%，早期胎儿死亡的检出率为63%，严重TTTS的检出率为52%。
约25%的单绒毛膜双胎中NT差异达20%或更大，在该组中早期胎儿死亡或发展为严重TTTS的风险超过30%。如果差异小于20%，并发症风险小于10%。
