Investigators: Dr Fabricio Costa (1), Andrew McLennan (2), Dr Simon Meagher (1), Dr Melody Menezes (1), Prof Jon Hyett (3)
1 Monash Ultrasound for Women, Clayton; 2 Sydney Ultrasound for Women, Burwood; 3 Royal Prince Alfred Hospital, Sydney
ART pregnancies have reduced first trimester combined screening (FTCS) PAPP-A levels leading to an increased likelihood of receiving a false-positive result. Non-invasive prenatal testing (NIPT) is a recently available advanced screening test which involves testing cell-free DNA (cfDNA) in the maternal plasma. These cells are released from the placenta (fetal genetic material) into the maternal circulation and this allows the detection of common autosomal trisomies (21, 18, and 13) with a high level of accuracy in singleton pregnancies. The objective of this study is to assess the performance of screening by NIPT for trisomies using a chromosome-selective sequencing method of cfDNA in maternal plasma obtained from an ART population undergoing routine screening at 11-13 weeks’ gestation. A prospective chart review will be conducted to collect clinical data on patients who will have undergone combined FTCS and NIPT. From the 300 patients studied a high risk on FTCS is expected in 24-30 cases (~8-10%). We will compare the risk scores, between FTCS and NIPT.
Reference: McLennan A, Palma-Dias R, da Silva Costa F, Meagher S, Nisbet DL, Scott F. Noninvasive prenatal testing in routine clinical practice – An audit of NIPT and combined first-trimester screening in an unselected Australian population. Aust N Z J Obstet Gynaecol. 2016 Feb;56(1):22-8.