Given that majority (>80%) of dual pregnancies was dichorionic, monochorionic pregnancies are from the bad perinatal consequences, are influenced by multiple criteria specific so you’re able to twins discussing a great placental circulation and need way more antenatal surveillance. thirteen
The new signs open to determine chorionicity vary by gestation and, overall, the new diagnosis is much more perfect the sooner in pregnancy brand new twins are examined. Ahead of ten weeks gestation, the presence of several gestational – amniotic and you will yolk sacs – clearly makes reference to a dichorionic diamniotic (DCDA) pregnancy. twelve Just after ten weeks, just how many placental public is known however, while the monochorionic placentae can be bilobar which means arrive while the one or two type of people, it marker are assessed within the perspective regarding almost every other evidence away from chorionicity such as for example intertwin membrane thickness, fetal sex and you can levels throughout the intertwin membrane.
The presence of good chorionic top or even the ‘lambda sign’ ( Profile step one(a) ) always ways a dichorionic pregnancy in comparison to the ‘T sign’ ( Figure 1(b) ) which is of an effective monochorionic maternity. It sign resembles the newest occurrence of the intertwin membrane which in an excellent DCDA maternity is made of upwards four layers (chorion/amnion/amnion/chorion) that create new heavier weight ‘chorionic peak’ in comparison to the twice coating (amnion/amnion) in the monochorionic (MCDA) pregnancies. several,14 From inside the monochorionic monoamniotic (MCMA) pregnancies no membrane is visible, however, a careful test has to take input order to help you exclude the clear presence of a thinner free floating intertwin membrane. Read More