University Hospitals Leuven, Division of Woman and Child, Department of Obstetrics and Gynecology, Fetal Diagnosis and Therapy Unit, Leuven, Belgium.
Ultrasound Obstet Gynecol. 2011 Jan;37(1):15-21. doi: 10.1002/uog.8802.
The aim of this study was to identify predictors of twin-to-twin transfusion syndrome (TTTS) and selective intrauterine growth restriction (sIUGR) in monochorionic diamniotic (MCDA) twin pregnancies with moderate amniotic fluid discordance (mAFD).
Monochorionic twins with mAFD (n = 45; gestational age, 15-29 weeks) were assessed for extent of fluid discordance, fetal growth discordance and fetal cardiac dysfunction, and were followed longitudinally. A prediction algorithm was constructed for TTTS and sIUGR and validated in an unrelated cohort (n = 52).
Cardiac dysfunction could not predict TTTS or sIUGR. Twins below 20 weeks of gestation with a fluid discordance of ≥ 3.1 cm had a risk of TTTS of 85.7%. Sensitivity for TTTS was nevertheless only 55%. An intertwin weight discordance of ≥ 25% had 63% sensitivity and 76% specificity for sIUGR without TTTS.
The outcome of MCDA twins with mAFD remains unpredictable, yet high-risk and low-risk subgroups for TTTS can be identified based on severity of fluid discordance and gestational age.
本研究旨在确定中孕期羊水偏少（mAFD）的单绒毛膜双羊膜囊（MCDA）双胎妊娠中双胎输血综合征（TTTS）和选择性胎儿宫内生长受限（sIUGR）的预测因素。
对 mAFD（n=45；孕龄 15-29 周）的 MCDA 双胎进行羊水差异程度、胎儿生长差异程度和胎儿心功能障碍评估，并进行纵向随访。构建了 TTTS 和 sIUGR 的预测算法，并在一个不相关的队列（n=52）中进行了验证。
心功能障碍不能预测 TTTS 或 sIUGR。孕龄＜20 周且羊水差异≥3.1cm 的双胎发生 TTTS 的风险为 85.7%。但 TTTS 的敏感性仅为 55%。无 TTTS 的情况下，双胎体重差异≥25%对 sIUGR 的敏感性为 63%，特异性为 76%。
MCDA 双胎妊娠中羊水偏少的结局仍然不可预测，但可以根据羊水差异严重程度和孕龄确定 TTTS 的高危和低危亚组。
