SCA type | Screening positive, n | True-positive results | False-positive results | Unknown karyotype | PPV, % | TOP |
---|
45,X | 21 | 3 | 11 | 7 | 3/14(21.4) | 2 |
47,XXX | 6 | 3a | 1 | 2 | 3/4(75.0) | 3 |
47,XXY | 12 | 10b | 1 | 1 | 10/11(90.9) | 11c |
47,XYY | 5 | 3d | 1 | 1 | 3/4(75.0) | 3 |
All SCAs | 44 | 19 | 14 | 11 | 19/33(57.6) | 19 |
- Of those with positive screening results for sex chromosome abnormalities, karyotypic information was available in 33 cases, and the PPV, positive predictive value of a prenatally confirmed SCA after an invasive test
- a-Includes a case at high risk for both trisomy 18 and XXX (true-positive for both)
- b-One Mosaic of 47,XXY[96]/46,XY[4]
- c-One 47,XXY case of negative confirmation by karyotype found to be X chromosomal microdeletions has chosen termination of pregnancy too
- d-One Mosaic of 47,XXY[35]/46,XY[51]
- Abbreviation: TOP Termination of pregnancy