Table 1 Maternal characteristics in the study population, n = 3238

Maternal age (years)

 <24

97 (3)

 25-29

774 (24)

 30-34

1363 (42)

 35-39

789 (24)

 ≥40

215 (7)

 Mean (SD)

32 (5)

 Missing data; 0

Parity

 Nulliparous

1960 (61)

 Multiparous

1278 (39)

 Missing data. O

Danish language skills

 Yes

3068 (96)

 No

132 (4)

 Missing data: 38

Cohabitation

 Yes

2949 (93)

 No

236 (7)

 Missing data; 53

Education

 Compulsory school

194 (7)

 Skilled

106 (4)

 Tertitary

210 (7)

 Bachelor or equivalent

897 (31)

 Master or equivalent

1451 (51)

 Missing data: 380

Occupation

 Working

2066 (71)

 Unemployed

166 (6)

 Student

464 (16)

 Other^a

206 (7)

 Missing data: 336

BMI (kg/m²)

 Underweight (<18.5)

154 (5)

 Normal (18.5-24.9)

2291 (77)

 Overweight (25–29.9)

398 (14)

 Obese (>30)

126 (4)

 Mean (SD)

23 (4)

 Missing data: 269

Chronic illness

 Yes

272 (9)

 No

2399 (82)

 Other illness^b

255 (9)

 Missing data: 312