Table 1

Maternal and infant characteristics by employment status, Amsterdam Born Children and their Development study, Amsterdam, the Netherlands, 2003–2004 (N=7561)

Mean (SD) or %Mean (SD) or %
Maternal age (years)31.8 (4.3)29.7 (5.5)
Pre-pregnancy body mass index (kg/m2)22.8 (3.5)23.9 (4.6)
Parity (% primiparae)61.840.2
Education (years)9.9 (3.4)6.6 (4.3)
Marital status (% single)9.817.8
Smoked while pregnant (% yes)8.410.6
Alcohol use while pregnant (% yes)26.612.4
 Other Western4.221.4
 Other non-Western14.610.8
Hypertensive disorder (%)
 Pre-existent hypertension3.34.5
 Pregnancy-induced hypertension15.35.4
 Previous preterm birth (% yes)0.8
 Gestational age (weeks)40.1 (1.2)40.0 (1.2)
 Birth weight (g)3510 (483)3478 (482)
 Gender of the baby (% boys)50.150.7
 Preterm birth (% yes)5.25.7