Table 1.
Descriptives for maternal characteristics and fetal measurements.
| N (Pregnancies) | 13,775 | |
|---|---|---|
| Categorical variables | Number | % |
| Parity | ||
| Nulliparous | 6731 | 48.86 |
| One previous pregnancy | 4820 | 34.99 |
| Two previous pregnancies | 1541 | 11.19 |
| 3 or more previous pregnancies | 683 | 4.96 |
| Age | ||
| 19 and under | 717 | 5.21 |
| 20–40 | 12,803 | 92.94 |
| Over 40 | 254 | 1.84 |
| Offspring sex | ||
| Female | 6706 | 48.68 |
| Male | 7069 | 51.32 |
| Smoking | ||
| Ex smoker, non-smoker | 11,075 | 80.40 |
| Smoker | 2700 | 19.60 |
| Social class | ||
| Professional | 2193 | 15.92 |
| Managerial and technical | 3883 | 28.19 |
| Skilled non-manual | 1932 | 14.03 |
| Skilled manual | 1425 | 10.34 |
| Partly skilled | 1345 | 9.76 |
| Unskilled | 322 | 2.34 |
| Not available | 2675 | 19.42 |
| Continuous variables | Mean | |
| Maternal height (cm) | 163.75 | |
| Maternal weight (kg) | 68.60 | |