Study (First author/year) | Location | DNA extraction tool | Exons targeted | Controls | Reference standard | Gestational age at time of NIPT (median/range) | Sample sizeα | Confirmed RhD positive | Confirmed RhD negative | Inconclusive test results (%) | Reasons for inconclusive results (n of cases) |
---|---|---|---|---|---|---|---|---|---|---|---|
Akolekar 2011 [19] | UK (London) | MDx BioRobot (Qiagen) | 5 and 7 | RhD+, RhD–, RHDΨ +, No DNA | “Serologically at delivery” | 12.4 (11–14) | 586 | 410 | 176 | 84 (14.3) | Maternal or fetal RHD variant and insufficient maternal plasma for further analysis (NR)! |
Banch Clausen 2014 [6] | Denmark | QIAsymphony SP; MagNA Pure LC; MagNA Pure Compact Instrument (Roche) | 5 and 10, or 5 and 7, or 7 and 10 | RhD+, RhD–£ | Cord blood serology~ | 25 (23–28) | 12,668 | 7830 | 4838 | 274 (2.2) | Maternal weak D (93); maternal silent RHD variant (38); high level of maternal background DNA (29); technical problems (19); maternal DVI (14); weak PCR signal (13); suspected maternal RHD positive (3); no reported cause (65) |
Chitty 2014 [16] | UK (Bristol) | MDx BioRobot (Qiagen) | 5 and 7 | RhD+, RhD–, RHDΨ+, No DNA | Cord blood serology | 19 (5–35) | 4913 | 2890 | 2023 | 393 (8.0) | NR |
Finning 2008 [17] | UK (Bristol) | MDx BioRobot (Qiagen) | 5 and 7 | RhD+, RhD–, RHDΨ+, No DNA | Cord blood serology> | 28 (8–38) | 1869 | 1156 | 713 | 56 (3.0) | Insufficient DNA (30); suspected maternal RHD gene (25); failure to extract DNA from plasma (1) |
Grande 2013 [25] | Spain | COBAS AmpliPrep (Roche) | 5 and 7, 10$ | RhD+, RhD– | Cord blood serology | 24–26 | 282 | 186 | 96 | NR | NR |
Soothill 2015 [18] | UK (Bristol) | MDx BioRobot (Qiagen) | 5 and 7 | RhD+, RhD–, RHDΨ+, No DNA | Cord blood serology | 15–17 (mostly) | 499* | 315 | 184 | 61 (12.2) | NR |
Thurik 2015 [7] | Netherlands | MagNa Pure 96 (Roche) | 5 and 7 | RhD+, RhD– | Cord blood serology^ | 26 | 18383* | 11,283 | 7100 | NR | NR |
Wikman 2012 [20] | Sweden | MagNA Pure LC (Roche) | 4 | GAPDH | Serology from cord blood or citrate samples from newborns+ | 8–40 | 3291# | 2073 | 1218 | 32 (1.0) | RHD variant (14); no second sample (18, of which 13 were spontaneous abortions and miscarriages) |