Table 1 Self-reported maternal demographics at postnatal enrolment

Number of women (n, %)

1757

769 (43.8)

988 (56.2)

Maternal age, years (mean, SD)

32.7 (5.5)

32.9 (5.8)

32.6 (5.2)

0.3538

 Black/Black mixed

263 (15.0)

145 (18.9)

118 (11.9)

< 0.0001

 Asian/Asian mixed

187 (10.7)

78 (10.1)

109 (11.0)

 White

1230 (70.0)

508 (66.1)

722 (73.1)

 Other

75 (4.3)

37 (4.8)

38 (3.9)

 Missing

2 (0.1)

1 (0.1)

1 (0.1)

First baby

1076 (61.3)

501 (65.2)

575 (58.2)

0.003

Singleton baby

1712 (97.4)

739 (96.1)

973 (98.5)

0.002

 Chronic

84 (10.9)

Not applicable

 Gestational

240 (31.2)

 Pre-eclampsia

311 (40.4)

 Eclampsia

6 (0.8)

 HELLP syndrome

15 (2.0)

 Hypertension (not specified)

202 (26.3)

Education level beyond secondary

1375 (78.3)

587 (76.3)

788 (79.8)

0.086

Currently employed (self-reported)

1321 (75.2)

569 (74.0)

752 (76.1)

0.311

Living with others

1554 (88.5)

668 (86.9)

886 (89.7)

0.069

Any risk factors for hypertension

1395 (79.4)

684 (89.0)

711 (72.0)

< 0.0001

Any mental health condition

307 (17.5)

149 (19.4)

158 (16.0)

0.064

 Spontaneous vaginal birth

1062 (60.4)

421 (54.8)

641 (64.9)

 Elective c-section

304 (17.3)

117 (15.2)

187 (18.9)

 Planned induction (vaginal birth)

289 (16.5)

157 (20.4)

132 (13.4)

 Not discussed - delivered early

24 (1.4)

20 (2.6)

4 (0.4)

 Not discussed – other

78 (4.4)

54 (7.0)

24 (2.4)

 Body mass index, kg/m² (median, IQR)

26 (22.5–30.7)

27 (23.4–32.5)

25 (22–29)

< 0.0001

 Current smoker

97 (5.5)

46 (6.0)

51 (5.2)

0.458

Positive to either Whooley question

124 (7.1)

64 (8.3)

60 (6.1)

OR 1.39 (0.97–2.02)

Missing

134 (7.6)

56 (7.3)

78 (7.9)