Table 1 Baseline characteristics of the study population

Age (years)

30.8 ± 4.9

32.2 ± 4.4

0.010

Height (cm) ^b)

168 ± 6

169 ± 6

0.202

Pregravid weight (kg) ^b)

63.0 (57.8 - 76.0)

62.0 (56.0 - 69.0)

0.026

Pregravid BMI (kg/m ² )

22.8 (20.6 - 26.6)

21.7 (19.9 - 23.7)

0.003

Weight at booking (kg) ^{c) d)}

64.9 (59.4 - 78.1)

63.7 (58.0 - 70.8)

0.042

BMI at booking (kg/m ² ) ^d)

23.3 (21.2 - 26.8)

22.2 (20.7 - 24.3)

0.008

Gestational age at booking (wk) ^d)

7 (6 - 8)

9 (8 - 11)

<0.0001

Pregravid BMI category

 Normal weight

57 (68.7)

140 (83.8)

0.009

 Overweight

15 (18.1)

20 (12.0)

 Obese

11 (13.3)

7 (4.2)

Parity

 0

53 (63.9)

110 (65.9)

0.385

 1

23 (27.7)

50 (29.9)

 ≥ 2

7 (8.4)

7 (4.2)

Country of birth

 Germany

68 (81.9)

140 (83.8)

0.704

 Others

15 (18.1)

27 (16.2)

Marital status

 Married

48 (57.8)

96 (57.5)

0.958

 Single/Divorced

35 (42.2)

71 (42.5)

Graduation

 None/General secondary school

7 (8.4)

8 (4.8)

0.101

 Intermediate secondary school

24 (28.9)

30 (18.0)

 High school/Grammar school

15 (18.1)

32 (19.2)

 University degree

37 (44.6)

97 (58.1)

Working status

 Full time

52 (62.7)

103 (61.7)

0.502

 Part time

17 (20.5)

43 (25.7)

 Not working

14 (16.9)

21 (12.6)

Smoking

 No

77 (92.8)

157 (94.0)

0.706

 Yes

6 (7.2)

10 (6.0)