Which statement about twin pregnancies is true regarding chorionicity?

In the context of twin pregnancies, the statement that dizygotic twins will always be dichorionic is accurate. Dizygotic twins, also known as fraternal twins, arise from two separate eggs fertilized by two separate sperm cells. Each twin develops its own placenta and chorion, leading to a dichorionic (two chorions) setup, which is the norm for dizygotic twins. This distinction is crucial for understanding the chorionicity in multiple pregnancies, as the presence of two separate placentas can significantly affect pregnancy management and fetal outcomes.

Chorionicity is essential because it informs clinicians about potential complications and care strategies during the pregnancy. For instance, monozygotic twins can have varying chorionicity depending on when the single fertilized egg splits, ranging from dichorionic to monochorionic (one chorion). However, dizygotic twins consistently have dichorionic placentation, making this statement true.