| Maternal variables | Number of mothers | Frequency (%) |
| Age (years) | ||
| Up to 20 | 14 | 20.0 |
| 20 to 30 | 36 | 51.4 |
| >30 | 20 | 28.6 |
| Number of children | ||
| 1 | 33 | 47.1 |
| 2 | 14 | 20.0 |
| 3 | 14 | 20.0 |
| ≥4 | 9 | 12.9 |
| Smoking habit | ||
| No | 52 | 74.3 |
| Yes | 18 | 25.7 |
| Alcoholic drink consumption | ||
| No | 70 | 100.0 |