Velamentous cord insertion in monochorionic twins with or without twin–twin transfusion syndrome: Does it matter?

Significance of Velamentous Cord Insertion for Twin-Twin Transfusion Syndrome

“…However, these studies were compromised by a small sample size and/or incomplete data. On the other hand, several recent studies came to an opposite conclusion [15,18,19]. These studies collected data from tertiary hospitals for complicated pregnancies; thus, they might not reflect the general twin population.…”

“…Several authors reported a strong correlation between VCI and the onset of TTTS [16,17], whereas other studies were not in agreement [15,18,19]. In addition, the correlation among VCI and intrauterine fetal growth restriction and severe birth weight discordance has also been reported [20,21,22].…”

Anomalies of the placenta and umbilical cord in twin gestations

“…[93][94][95][96] The incidence of VCI, vasa previa, or marginal cord insertion is higher in ART than in spontaneously conceived singletons but similar in both types of twins. 4,7,97 There is a 3-fold increase in the incidence of VCI in twins presenting with IUGR compared to normally grown twins.…”

“…96 In MC placenta, VCI is associated with a decreased blood flow in the umbilicoplacental circulation with additional risk factor for the vascular thrombosis and development of TTTS. [93][94][95] Vasa previa is a rare anomaly in both singleton and twin pregnancies but is more common in twins due to the higher incidence of VCI, bilobated placenta, and placenta previa. 98,99 (Figure 10).…”

First-Trimester Ultrasound

“…Furthermore, a variety of movements intervene during B-mode imaging, such as fetal body motion, observer's hand movements, and maternal breathing. However, several authors have demonstrated the feasibility of examining the heart much sooner in pregnancy, beginning around 10 or 11 weeks [131][132][133][134]. This is because, in general, blood vessels or heart valves are small in comparison to the general organ or body size being scanned and even small movements will have more undesired effects on the resulting image.…”