Table 1 Background characteristics of primiparous women aged 25–31 years (reference group) and ≥32 years (advanced age), and for representativeness; comparisons between a sub-sample giving birth in 2003 and all primiparous women aged >25 years in Norway in 2003 (P-value for differences between a sub-sample from 2003 and all Norwegian primiparous women >25 years giving birth in 2003)
From: Experience of childbirth in first-time mothers of advanced age – a Norwegian population-based study
Women in the study | Women ≥ 25 years giving birth in 2003 | |||||
|---|---|---|---|---|---|---|
Age 25-31 | Age ≥32 | All | Sub sample | Norway | ||
n=21 226 | n=8839 | n=30 065 | n=3549 | n=16 760 | ||
% | % | % | % | % | P-value | |
Demographic and social factors | ||||||
Age (years)* | 0.07 | |||||
25-29 | 50.8 | 55.2 | 54.0 | |||
30-34 | 37.6 | 35.2 | 35.1 | |||
35-39 | 10.3 | 8.8 | 9.6 | |||
≥40 | 1.3 | 0.8 | 1.2 | |||
Smoking* | 8.4 | 7.6 | 8.2 | 10.8 | 13.9 | <0.001 |
Single status | 2.9 | 4.9 | 3.5 | 2.7 | 5.7 | <0.001 |
Native language other than Norwegian | 5.9 | 8 | 6.5 | 4.7 | ||
Unemployed | 1.7 | 1.6 | 1.7 | |||
Income (NOR)** | ||||||
<200 000 | 11.2 | 6 | 8.7 | |||
200 000–399 999 | 55.5 | 43.7 | 51.5 | |||
≥400 000 | 29.1 | 46 | 33.7 | |||
Pregravid BMI, mean (kg/m2) | 23.6 | 24.1 | 23.8 | |||
IVF present pregnancy* | 2.6 | 8.9 | 4.4 | 3.8 | 4.9 | <0.001 |
Labour* | ||||||
Mode of delivery | ||||||
Vacuum | 14.2 | 16 | 14.8 | 14.1 | 13.7 | 0.54 |
Forceps | 2.8 | 3.4 | 3 | 2.7 | 2.4 | 0.27 |
Elective cesarean delivery | 3.1 | 6 | 4 | 3.8 | 5.3 | <0.001 |
Emergency cesarian delivery | 9.7 | 13.5 | 10.8 | 11.4 | 12.5 | 0.06 |
Unspecified cesarean delivery | 1.9 | 2.9 | 2.2 | 1.2 | 2.5 | <0.001 |
Prematurity** | 5.5 | 6.4 | 5.8 | 6.5 | 8.8 | <0.001 |
Neonatal Transfer | 9.2 | 10.8 | 9.3 | 10.8 | 12.5 | <0.001 |