What is a potential increase in risk for monoamniotic/monochorionic twins?

Monoamniotic/monochorionic twins share both an amniotic sac and a chorion, which leads to unique challenges and risks during pregnancy. The correct answer highlights the increased risk for perinatal mortality associated with this type of twin gestation.

This elevated risk primarily stems from factors such as cord entanglement and restricted space within the shared amniotic sac. As the fetuses grow, their umbilical cords may become intertwined or compressed, which can compromise blood flow and oxygen delivery to one or both twins. Additionally, the lack of separate amniotic sacs can result in oligohydramnios for one or both fetuses, further exacerbating the potential for complications.

While the other options address potential concerns in twin pregnancies, they are not as specifically linked to the unique circumstances of monoamniotic/monochorionic twins. For instance, while congenital heart defects and miscarriage do have associations within twin pregnancies, they are not predominant risk factors specific to monoamniotic/monochorionic twins. Similarly, while lower birth weight can occur in any multiple gestation, it is not uniquely tied to the conditions of these shared sacs and chorions as directly as the risk of perinatal mortality is.