Table 3.
Diagnostic performance of crown-rump length to predict miscarriage in pregnancies where embryo with no heart activity has been visualised. Sensitivity is based on 527 non-viable pregnancies; specificity on 110 viable pregnancies
| Crown-rump cut-off (mm) | Sensitivity* (n=527) | Specificity† (n=110) | Positive predictive value‡ (%) | |||
|---|---|---|---|---|---|---|
| No of women | % (95% CI) | No of women | % (95% CI) | |||
| 3.0 | 380 | 72.1 (68.1 to 75.8) | 86 | 78.2 (69.6 to 84.9) | 94 | |
| 3.5 | 308 | 58.4 (54.2 to 62.6) | 95 | 86.4 (78.7 to 91.6) | 95 | |
| 4.0 | 237 | 45.0 (40.8 to 49.2) | 99 | 90.0 (83.0 to 94.3) | 96 | |
| 4.5 | 172 | 32.6 (28.8 to 36.8) | 104 | 94.5 (88.6 to 97.5) | 97 | |
| 5.0 | 117 | 22.2 (18.9 to 25.9) | 106 | 96.4 (91.0 to 98.6) | 97 | |
| 5.5 | 80 | 15.2 (12.4 to 18.5) | 107 | 97.3 (92.3 to 99.1) | 96 | |
| 6.0 | 56 | 10.6 (8.3 to 13.6) | 109 | 99.1 (95.0 to 99.8) | 98 | |
| 6.2 | 38 | 7.2 (5.3 to 9.7) | 110 | 100 (96.6 to 100) | 100 | |
| 6.4 | 32 | 6.1 (4.3 to 8.5) | 110 | 100 (96.6 to 100) | 100 | |
| 6.6 | 26 | 4.9 (3.4 to 7.1) | 110 | 100 (96.6 to 100) | 100 | |
| 6.8 | 22 | 4.2 (2.8 to 6.2) | 110 | 100 (96.6 to 100) | 100 | |
| 7.0 | 17 | 3.2 (2.0 to 5.1) | 110 | 100 (96.6 to 100) | 100 | |
| 7.2 | 9 | 1.7 (0.9 to 3.2) | 110 | 100 (96.6 to 100) | 100 | |
| 7.4 | 8 | 1.5 (0.8 to 3.0) | 110 | 100 (96.6 to 100) | 100 | |
| 7.6 | 5 | 0.9 (0.4 to 2.2) | 110 | 100 (96.6 to 100) | 100 | |
| 7.8 | 5 | 0.9 (0.4 to 2.2) | 110 | 100 (96.6 to 100) | 100 | |
| 8.0 | 4 | 0.8 (0.3 to 1.9) | 110 | 100 (96.6 to 100) | 100 | |
*Percentage of non-viable pregnancies that met (≥) cut-off.
†Percentage of viable pregnancies that did not meet (<) cut-off.
‡Percentage of non-viable pregnancies among all pregnancies that met cut-off.