| Antecedent | Number of patients | Percentage |
| Prematurity | 3 | 4.92 |
| Epilepsy | 3 | 4.92 |
| Recurrent otitis | 6 | 9.83 |
| Meningitis | 2 | 3.22 |
| Fetal suffering | 8 | 13.11 |
| Growth retardation | 37 | 60.65 |
| Cesarean birth | 2 | 3.28 |
| Total | 61 | 100 |