Scope of Cell- Versus Cell-Free-Based Detection Approach in Noninvasive Prenatal Screening

Noninvasive prenatal screening (NIPS) represents an evolving method in prenatal testing. This approach has demonstrated success in detecting chromosomal abnormalities and other genetic defects associated with the fetus. At its core, this method relies on its noninvasive nature, which is predicated on specific fetal entities present in maternal circulation. These fetal entities encompass cell-free fetal nucleic acids such as cell-free fetal DNA or cell-free fetal RNA, as well as fetal cells like trophoblasts, nucleated red blood cells, or microsomes. Consequently, NIPS depends on these entities, which can be isolated from maternal blood using various techniques. Each of these methods possesses its own advantages and disadvantages, ultimately impacting their clinical efficacy. This chapter elucidates the role of cell-free fetal entities and cell-based entities like fetal cells in NIPS and explores their clinical significance in prenatal screening.