Table 1.
Study and baseline population characteristics among women participating in the Norwegian Mother Child Prospective Cohort Study (2004–2008)
| Baseline population* | Study population | ||
|---|---|---|---|
| n=44,649 % |
n=19,652 % |
||
| Maternal age (years) | |||
| 14–19 | 0.9 | 0.4 | |
| 20–29 | 42.1 | 40.3 | |
| 30–39 | 54.9 | 57.1 | |
| 40–49 | 2.1 | 2.3 | |
| Maternal BMI (kg/m2) | |||
| <18.5 | 3.2 | 2.9 | |
| 18.5–24.9 | 66.1 | 67.2 | |
| 25.0–29.9 | 21.7 | 21.8 | |
| ≥30.0 | 9.0 | 8.1 | |
| Parity | |||
| 0 | 47.1 | 50.0 | |
| 1 | 35.5 | 34.3 | |
| 2 | 13.7 | 12.4 | |
| 3 | 2.8 | 2.4 | |
| 4 or more | 0.9 | 0.8 | |
| Maternal education | |||
| More than 4 years of university or technical | 27.2 | 29.9 | |
| 4 year university degree, regional technical | 40.8 | 43.9 | |
| 3 years high school, junior college | 13.5 | 12.0 | |
| Technical high school | 11.2 | 9.3 | |
| 1–2 years high school | 3.9 | 2.6 | |
| 9-year secondary | 2.2 | 1.1 | |
| Other | 1.4 | 1.4 | |
| Maternal smoking (at 17 weeks) | |||
| None | 79.3 | 82.8 | |
| Quit | 14.5 | 12.6 | |
| Daily | 1.4 | 1.2 | |
| Sometimes | 4.8 | 3.4 | |
*
Represents unique pregnancies with no use of IVF treatment, resulting in a singleton live birth and no death in the first year of life, with a date of birth ≥12 months after NorPD registry began (January 1, 2004)