The Umbilical Cord and Complications of Twin Gestations

Abstract

The rate of twin pregnancies has increased over the last decades, largely because of the ongoing development of assisted reproductive technology and increased maternal age at childbearing. Twins have a higher risk of adverse outcomes during pregnancy and the perinatal period. The prevalence of umbilical cord abnormalities is higher for twin pregnancies compared with singleton pregnancies. Some of these abnormalities are nonspecific to twinning and can also be found in singleton gestations (such as velamentous cord insertion, vasa previa, and single umbilical artery). Other abnormalities are associated with monochorionic twins, such as umbilical cord entanglement, and umbilical proximate cord insertion. Most of these abnormalities can be detected by ultrasound evaluation. The early and accurate ultrasound diagnosis of chorionicity, amnionicity, and placental and umbilical cord characteristics is crucial if we are to predict the risk of complications and to determine the best management for twin pregnancies. Histopathological examination of the placenta and umbilical cord after delivery can help to confirm prenatal diagnosis and to provide a better understanding of the physiopathology of their abnormalities. The aim of this review was to emphasize the role that the umbilical cord plays in twin complications and to describe the management of these high-risk pregnancies.

Inpatient Management of a Monoamniotic Twin Pregnancy Complicated by Umbilical Cord Entanglement and Selective Intrauterine Growth Restriction

“…Monoamniotic twins are a rare occurrence, with an incidence of about one in 10,000 pregnancies [ 1 ]. Monoamniotic pregnancies result from the division of the embryonic disc between days nine and 13 post-fertilization, therefore both fetuses share the same placenta and amniotic sac [ 2 ].…”

“…Monoamniotic pregnancies result from the division of the embryonic disc between days nine and 13 post-fertilization, therefore both fetuses share the same placenta and amniotic sac [ 2 ]. These high-risk pregnancies may be complicated by a variety of conditions, including twin-twin transfusion syndrome (TTTS), twin reversed arterial perfusion sequence, intrauterine growth restriction (IUGR), congenital malformations, and exclusive to monoamniotic pregnancies, umbilical cord entanglement [ 1 ]. The mortality rate is as high as 30% [ 2 ].…”