Abstract：
Thirty percent of spontaneously occurring twins are monozygotic, of which two-thirds are monochorionic, possessing a single placenta. A common placental mass with shared intertwin placental circulation is key to the development and management of complications unique to monochorionic gestations. In this Consult, we review general considerations and a contemporary approach to twin-twin transfusion syndrome and twin anemia-polycythemia sequence, providing management recommendations based on the available evidence. The following are the Society for Maternal-Fetal Medicine recommendations: (1) we recommend routine first-trimester sonographic determination of chorionicity and amnionicity (GRADE 1B); (2) we recommend that ultrasound surveillance for twin-twin transfusion syndrome begin at 16 weeks of gestation for all monochorionic-diamniotic twin pregnancies and continue at least every 2 weeks until delivery, with more frequent monitoring indicated with clinical concern (GRADE 1C); (3) we recommend that routine sonographic surveillance for twin-twin transfusion syndrome minimally include assessment of amniotic fluid volumes on both sides of the intertwin membrane and evaluation for the presence or absence of urine-filled fetal bladders, and ideally incorporate Doppler study of the umbilical arteries (GRADE 1C); (4) we recommend fetoscopic laser surgery as the standard treatment for stage II through stage IV twin-twin transfusion syndrome presenting between 16 and 26 weeks of gestation (GRADE 1A); (5) we recommend expectant management with at least weekly fetal surveillance for asymptomatic patients continuing pregnancies complicated by stage I twin-twin transfusion syndrome, and consideration for fetoscopic laser surgery for stage I twin-twin transfusion syndrome presentations between 16 and 26 weeks of gestation complicated by additional factors such as maternal polyhydramnios-associated symptomatology (GRADE 1B); (6) we recommend an individualized approach to laser surgery for early- and late-presenting twin-twin transfusion syndrome (GRADE 1C); (7) we recommend that all patients with twin-twin transfusion syndrome qualifying for laser therapy be referred to a fetal intervention center for further evaluation, consultation, and care (Best Practice); (8) after laser therapy, we suggest weekly surveillance for 6 weeks followed by resumption of every-other-week surveillance thereafter, unless concern exists for post-laser twin-twin transfusion syndrome, post-laser twin anemia-polycythemia sequence, or fetal growth restriction (GRADE 2C); (9) following the resolution of twin-twin transfusion syndrome after fetoscopic laser surgery, and without other indications for earlier delivery, we recommend delivery of dual-surviving monochorionic-diamniotic twins at 34 to 36 weeks of gestation (GRADE 1C); (10) in twin-twin transfusion syndrome pregnancies complicated by posttreatment single fetal demise, we recommend full-term delivery (39 weeks) of the surviving co-twin to avoid complications of prematurity unless indications for earlier delivery exist (GRADE 1C); (11) we recommend that fetoscopic laser surgery not influence the mode of delivery (Best Practice); (12) we recommend that prenatal diagnosis of twin anemia-polycythemia sequence minimally require either middle cerebral artery Doppler peak systolic velocity values >1.5 and <1.0 multiples of the median in donor and recipient twins, respectively, or an intertwin Δ middle cerebral artery peak systolic velocity >0.5 multiples of the median (GRADE 1C); (13) we recommend that providers consider incorporating middle cerebral artery Doppler peak systolic velocity determinations into all monochorionic twin ultrasound surveillance beginning at 16 weeks of gestation (GRADE 1C); and (14) consultation with a specialized fetal care center is recommended when twin anemia-polycythemia sequence progresses to a more advanced disease stage (stage ≥II) before 32 weeks of gestation or when concern arises for coexisting complications such as twin-twin transfusion syndrome (Best Practice).
摘要：
30％的自发发生的双胞胎是单卵，其中三分之二是单绒毛膜，拥有一个胎盘。具有共享的双胎间胎盘循环的常见胎盘肿块是单绒毛膜妊娠特有并发症的发展和管理的关键。在这次咨询中,我们回顾了对双胎输血综合征和双胎贫血红细胞增多症序列的一般考虑和当代方法，根据现有证据提供管理建议。以下是母胎医学协会的建议：（1）我们建议常规的妊娠早期超声检查绒毛膜和羊膜性（GRADE1B）；（2）我们建议双胎输血综合征的超声监测在妊娠16周时开始，所有单绒毛膜双胎双胎妊娠，并至少每2周持续一次，直至分娩，更频繁的监测表明有临床关注（GRADE1C）；（3）我们建议双胎输血综合征的常规超声监测最低限度地包括评估双胎膜两侧的羊水量以及评估是否存在尿液充满的胎儿膀胱，理想地结合了脐动脉的多普勒研究（GRADE1C）；（4）我们建议胎儿镜激光手术作为II期至IV期双胎输血综合征的标准治疗方法，表现在妊娠16至26周（GRADE1A）；（5）我们建议对无症状妊娠合并I期双胎输血综合征的患者进行至少每周胎儿监测，并考虑在妊娠16至26周之间进行I期双胎输血综合征的胎儿镜激光手术，并伴有其他因素，例如产妇羊水过多相关症状（GRADE1B）；（6）我们建议采用个体化的激光手术方法治疗早期和晚期双胎输血综合征（GRADE1C）；（7）我们建议所有双胎输血综合征患者均有资格接受激光治疗的转诊至胎儿中心进行进一步评估，协商,和护理（最佳实践）；（8）激光治疗后，我们建议每周监测6周，然后恢复每隔一周的监测，除非担心激光后双胎输血综合征,激光后双胎贫血红细胞增多症序列，或胎儿生长受限（GRADE2C）；（9）在胎儿镜激光手术后双胎输血综合征消退后，没有其他提前交货的迹象，我们建议在妊娠34至36周（GRADE1C）分娩双胎存活的单绒毛膜-双胎输血综合征妊娠合并治疗后单个胎儿死亡，我们建议存活的双胎足月分娩（39周），以避免早产并发症，除非有提前分娩的指征（GRADE1C）；（11）我们建议胎儿镜激光手术不应影响分娩方式（最佳实践）；（12）我们建议产前诊断双胎贫血红细胞增多症序列最低限度要求大脑中动脉多普勒收缩期峰值速度值>1.5倍的供体中位数和<1.0倍的供体接受者分别,或双胎间Δ大脑中动脉收缩期峰值速度>中位数的0.5倍(GRADE1C);(13)我们建议提供者考虑将大脑中动脉多普勒收缩期峰值速度测定纳入所有从妊娠16周开始的单绒毛膜双胎超声监测(GRADE1C);(14)当双胎贫血红细胞增多症序列进展到更晚期的疾病阶段(≥II期)时,建议与专门的胎儿护理中心进行咨询,如双
