Table 3 Risk ratios showing association between postnatal depression and sociodemographic and pregnancy and birth-related factors

Sociodemographic factors

 Age group

   ≤ 24 years

93

29 (30.1%)

1.23 (0.80–1.89)

NS

  25–29 years

213

45 (21.8%)

0.89 (0.62–1.29)

  30–34 years

337

77 (24.4%)

1

  35 + years

292

60 (20.5%)

0.84 (0.61–1.17)

 Country of birth

  UK

734

172 (24.6%)

1

NS

  Outside UK

197

37 (21.7%)

0.88 (0.61–1.28)

 Ethnicity

  White-British

780

177 (24.1%)

1

NS

  Other

128

27 (21.5%)

0.89 (0.59–1.34)

 IMD quintile

  (Least advantaged) 1

164

44 (25.3%)

1.25 (0.82–1.90)

NS

  2

192

43 (24.3%)

1.20 (0.76–1.89)

  3

187

43 (22.6%)

1.12 (0.73–1.70)

  4

209

45 (24.3%)

1.20 (0.80–1.80)

  (Most advantaged) 5

183

36 (20.2%)

1

 Age when leaving education

  16 years or less

111

37 (31.2%)

1.39 (0.97–2.00)

NS

  17–18 years

247

56 (23.3%)

1.04 (0.75–1.45)

  19 years or over

564

115 (22.4%)

1

 Living with partner

  Yes

836

186 (23.9%)

1

NS

  No

99

25 (23.2%)

0.97 (0.61–1.55)

 Social support ^#

932 (6, 4–7)

209 (4,3–6)

0.76 (0.72–0.81)*

0.78 (0.73–0.84)

 Long-term mental health problem

  Yes

118

70 (60.8%)

3.38 (2.64–4.33)*

2.15 (1.59–2.90)

  No

810

139 (18.0%)

1

1

Pregnancy and birth related factors

 Parity

  Primiparous

595

125 (22.9%)

1

NS

  Multiparous

324

83 (25.3%)

1.11 (0.83–1.47)

 Multiplicity

  Singleton

877

200 (24.0%)

1

NS

  Multiple birth

57

11 (19.0%)

0.79 (0.44–1.43)

 Pregnancy Planning

  Planned

735

154 (22.5%)

1

NS

  Unplanned

189

56 (28.1%)

1.25 (0.92–1.70)

 Satisfaction with labour and birth ^#

888 (7, 5–9)

200 (6, 4–8)

0.89 (0.85–0.92)*

0.94 (0.90–0.97)

 Gestation at birth

  Very pre-term

62

14 (28.6%)

1.21 (0.75–1.96)

NS

  Pre-term

233

50 (23.6%)

1.00 (0.70–1.43)

  Term

630

144 (23.6%)

1

 Birth weight

  Very low birthweight

56

13 (28.0%)

1.15 (0.69–1.91)

NS

  Low birthweight

207

41 (22.7%)

0.93 (0.63–1.37)

  Normal birthweight

647

153 (24.4%)

1

 Length of stay in NNU

  24 h or less

225

40 (17.7%)

1

NS

  25 h to 7 days

391

90 (24.1%)

1.37 (0.93–2.01)*

  8 to 28 days

165

36 (20.3%)

1.15 (0.72–1.82)*

  More than 28 days

85

22 (32.4%)

1.84 (1.12–3.01)*

 Mode of birth

  Vaginal

365

79 (21.9%)

1

NS

  Assisted vaginal

143

33 (25.7%)

1.17 (0.73–1.88)

  Planned caesarean

154

39 (24.9%)

1.14 (0.78–1.66)

  Unplanned caesarean

268

60 (25.2%)

1.15 (0.82–1.61)

 Antenatal anxiety

  Yes

194

93 (49.8%)

3.04 (2.34–3.95)*

1.65 (1.19–2.27)

  No

738

117 (16.4%)

1

1

 Antenatal depression

  Yes

74

41 (54.7%)

2.65 (1.99–3.54)*

NS

  No

858

169 (20.6%)

1

 Smoking during pregnancy

  Yes

61

25 (36.5%)

1.81 (1.21–2.72)*

NS

  No

595

113 (20.2%)

1

 Household smoking/passive smoking during pregnancy

  Yes

152

36 (24.1%)

1.02 (0.68–1.53)

NS

  No

758

167 (23.6%)

1

 Survey year

  2018

485

82 (19.4%)

1

1

  2020

450

129 (27.8%)

1.44 (1.08–1.90)*

1.17 (0.89–1.53)