Contingent prenatal screening for frequent aneuploidies with cell-free fetal DNA analysis.

Objective: To analyze the results of contingent screening for common aneuploidies at our center from June 2017 to June 2019.

Materials And Methods: Traditional screening tests were performed using a combination of biochemical markers and ultrasound measurements in the first and second trimesters to assess the risk of trisomies 21 (T21), 18 (T18) and 13 (T13). Cell-free DNA (cf-DNA) testing was offered (Harmony test) to pregnant women at high risk (>1/280 for T21 and > 1/150 for T13 and T18) and a normal early morphology scan.

Assessment of a change of protocol of prenatal screening by inclusion of non-invasive prenatal diagnosis.

Objectives: Non-invasive prenatal screening (NIPS) is a test for the detection of major fetal chromosomal abnormalities in maternal blood during pregnancy. The purpose of this study was to assess the performance of NIPS implemented within the framework of the Screening Program for Congenital Abnormalities of the Andalusian Health System.

Methods: A retrospective observational study was undertaken to determine the number of NIPS tests performed since its introduction.