| Gestation weeks | ACS given | No ACS | P Value |
| N (%) | N (%) | ||
| 27 | 7 (38.9) | 3 (75.0) | 0.190 |
| 28 | 7 (35.0) | 32 (36.0) | 0.936 |
| 29 | 6 (40.0) | 4 (22.2) | 0.269 |
| 30 | 10 (43.5) | 10 (29.4) | 0.275 |
| 31 | 4 (16.7) | 5 (23.8) | 0.550 |
| 32 | 4 (9.5) | 22 (25.0) | 0.039 |
| 33 | 8 (12.7) | 8 (22.9) | 0.193 |
| 34 | 12 (11.9) | 24 (18.5) | 0.171 |