Why is SNP-based prenatal testing supplanting US as the definitive test to distinguish chorionicity and zygosity? And how early can this test be performed?

Why is SNP-based prenatal testing supplanting US as the definitive test to distinguish chorionicity and zygosity? And how early can this test be performed?

Why is SNP-based prenatal testing on women with twins clinically important and why is there an urgency to make the diagnosis and initiate evaluation to determine chorionicity and zygosity? Can you provide an overview of how NIPT and surveillance in twins can improve clinical outcomes and reduce the incidence of possible complications?