Table 4.
Incidence of aneuploidy and CNV in NT < 3.5 mm and ≥ 3.5 mm subgroups.
| Chromosomal abnormalities and structural anomalies | NT cut-off | <2.5 | ≥2.5 | χ2 | <3.0 | ≥3.5 | χ2 | <3.5 | ≥3.5 | χ2 | P | P | P | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chromosomal | Normal | 148 (98.7) |
101 (88.6) |
196 (97.5) |
53 (84.1) |
216 (97.3) |
33 (78.6) |
Aneuploidy | 2 (1.3) | 10 (8.8) |
8.569 0.003 |
3 (1.5) | 9 (14.3) |
18.237 <0.001 |
4 (1.8) | 8 (19.0) |
24.667 <0.001 |
Pathogenic CNVs |
0 (0.0) | 3 (2.6) | 4.321 0.069 |
2 (1.0) | 1 (1.6) | 0.256 0.517 |
2 (0.9) | 1 (2.4) | 1.024 0.354 |
|||
| Structural | Normal | 141 (94.0) |
81 (71.1) |
187 (93.0) |
35 (55.6) |
203 (91.4) |
19 (45.2) |
Structural defects |
9 (6.0) | 33 (28.9) |
25.496 <0.001 |
14 (7.0) |
28 (44.4) |
50.364 <0.001 |
19 (8.6) |
23 (54.8) |
56.357 <0.001 |