Table 1. Descriptive statistics for the population.
| GIRLS | BOYS | |
|---|---|---|
| Newborn characteristics | Percentage | Percentage |
| Birth Weight (gr)* | 3265 (σ = 456) | 3392 (σ = 477) |
| Low Birth Weight | 4.4% | 3.2% |
| Term Low Birth Weight | 2.5% | 1.4% |
| Parent characteristics | ||
| Maternal age | ||
| <20 years | 0.6% | 0.6% |
| [20–25] years | 6.4% | 6.4% |
| [25–35] years | 59.3% | 59.7% |
| [35–40] years | 25.9% | 25.7% |
| ≥ 40 years | 7.8% | 7.6% |
| Maternal level of education | ||
| Primary | 17.9% | 18.1% |
| Secondary | 12.5% | 12.7% |
| High School | 15.6% | 15.3% |
| University | 54.0% | 53.9% |
| Maternity Classification | ||
| Class I | 28.0% | 27.7% |
| Class II | 42.8% | 42.8% |
| Class III | 29.2% | 29.4% |
| Woman’s first pregnancy | 50.9% | 51.4% |
| Maternal occupational status | 26.2% | 26.2% |
| Paternal occupational status | 20.3% | 20.1% |
* We gave the mean (standard deviation) of birth weight expressed in grams, as it is a quantitative variable.