Table 1.
Characteristics of 4322 Norwegian women in the Cohort of Norway, 1994–2003, with no, 1 or ≥2 children
| Mean values | 1677 no child | 488 one child | 2157 ≥2 children |
| Age (SD) at examination | 30.5 (2.1) | 29.5 (5.2) | 26.7 (4.0) |
| Age (SD) at first delivery | – | 32.3 (4.9) | 29.9 (3.8) |
| Years (SD) from examination to first pregnancy | – | 3.7 (2.1) | 4.1 (2.3) |
| BMI (SD) at examination* | 24.8 (5.1) | 24.2 (4.5) | 23.5 (3.4) |
| OC use* | |||
| Now | 455 (27.4) | 168 (34.6) | 1047 (48.9) |
| Previously | 724 (43.5) | 239 (49.2) | 779 (36.4) |
| Never | 484 (29.1) | 79 (16.3) | 317 (14.8) |
| Smoking at examination* | |||
| Yes | 537 (32.2) | 182 (37.4) | 462 (21.5) |
| No | 1132 (67.8) | 304 (62.6) | 1685 (78.5) |
| Education* | |||
| <11 years | 312 (18.8) | 127 (26.3) | 300 (14.1) |
| ≥11 years | 1344 (81.2) | 356 (73.7) | 1834 (85.9) |
Values are numbers (percentages) unless stated otherwise.
*Missing data on smoking: 8 nulliparous, 2 one-child mothers and 10 women with ≥2 children; BMI, 10 nulliparous; education, 21 nulliparous, 5 one-child mothers and 23 women with ≥2 children; OC use: 4 nulliparous, 2 one-child mothers and 14 women with ≥2 children.
BMI, body mass index; OC, oral contraceptive.