Table 2 Odds ratios for different durations of exclusive breastfeeding from a multinomial logistic regression in the whole sample with GDM status, maternal age, parity, deprivation category, BMI and baby birthweight entered as predictor variables

GDM status (total n = 2,866)

GDM (n = 1,649)

1.36 (0.99–1.86)

0.059

1.12 (0.89–1.41)

0.331

0.26 (0.08–0.80)

0.019

0.61 (0.42–0.88)

0.008

0.60 (0.44–0.81)

0.001

No GDM (n = 1,728)

1.00

Maternal age at delivery (total n = 4,944)

1.04 (1.02–1.07)

< 0.001

1.05 (1.03–1.07)

< 0.001

1.02 (0.95–1.10)

0.594

1.04 (1.02–1.07)

0.003

1.09 (1.07–1.11)

< 0.001

Parity (total n = 2,443)

Nulliparous (n = 1,339)

2.24 (1.71–2.94)

< 0.001

1.49 (1.21–1.83)

< 0.001

3.28 (1.33–8.09)

0.010

2.4 (1.75–3.38)

< 0.001

1.73 (1.31–2.30)

< 0.001

Multiparous (n = 2,038)

1.00

SIMD quintile (total n = 2,181)

1 (most deprived, n = 890)

0.54 (0.35–0.84)

0.006

0.32 (0.24–0.44)

< 0.001

0.51 (0.14–1.89)

0.310

0.38 (0.23–0.61)

< 0.001

0.30 (0.20–0.46)

< 0.001

2 (n = 720)

0.64 (0.41-1.00)

0.052

0.42 (0.31–0.58)

< 0.001

0.46 (0.11–1.93)

0.289

0.48 (0.29–0.79)

0.004

0.36 (0.23–0.55)

< 0.001

3 (n = 653)

0.75 (0.47–1.18)

0.210

0.52 (0.38–0.73)

< 0.001

0.55 (0.13–2.29)

0.412

0.39 (0.23–0.69)

< 0.001

0.47 (0.31–0.72)

< 0.001

4 (n = 562)

0.94 (0.58–1.51)

0.793

0.58 (0.41–0.82)

0.002

0.80 (0.20–3.31)

0.761

0.80 (0.48–1.33)

0.376

0.67 (0.44–1.03)

0.065

5 (least deprived, n = 552)

1.00

BMI (n = 2,702)

Normal (n = 834)

0.69 (0.47-1.00)

0.052

1.64 (1.26–2.12)

< 0.001

1.13 (0.34–3.7)

0.846

1.04 (0.67–1.60)

0.876

2.98 (2.01–4.30)

< 0.001

Overweight (n = 651)

0.95 (0.67–1.33)

0.746

1.45 (1.13–1.88)

0.004

1.95 (0.63–6.10)

0.250

1.66 (1.12–2.48)

0.012

2.69 (1.87–3.86)

< 0.001

Obese (n = 1217)

1.00

Birthweight baby kg (n = 4,478)

1.04 (1.02–1.07)

0.001

1.04 (1.02–1.06)

< 0.001

1.03 (0.95–1.12)

0.486

1.31 (1.00-1.06)

0.047

1.07 (1.05–1.10)

< 0.001