| Variable | Frequency (n = 39) | Percent |
| Malformations |
|
|
| Spina bifida | 12 | 30.8 |
| Dandy -Walker | 2 | 5.1 |
| Omphalocele | 1 | 2,5 |
| Congenital infectious causes | 10 | 25.6 |
| unknown causes | 14 | 35.9 |