Table 3C.

Risk factors for study outcomes, multivariable estimates (all included women)

Characteristics	Study outcomes
	Caesarean sections n=16 693, 23% RR (95% CI)†	Pregnancy-related maternal complications n=10 163, 14% RR (95% CI)†	Stillbirths n=1620, 2.2% RR (95% CI)†	Neonatal deaths (within 28 days of birth) n=1368, 1.9% RR (95% CI)†	Low birth weight (<2500 g) n=12 347, 17% RR (95% CI)†
Mother’s age (years)
<20	0.80** (0.72 to 0.90)	0.83* (0.73 to 0.95)	0.88 (0.62 to 1.25)	1.28 (0.94 to 1.75)	1.04 (0.92 to 1.16)
20–29	Ref	Ref	Ref	Ref	Ref
>29	1.60** (1.50 to 1.70)	1.38**(1.26 to 1.50)	1.76**(1.45 to 2.12)	1.47**(1.18 to 1.83)	1.28**(1.18 to 1.38)
Mother’s education (grades)
Primary or less (≤4)	0.47** (0.44 to 0.50)	0.69** (0.64 to 0.74)	1.62** (1.38 to 1.89)	1.49** (1.26 to 1.77)	1.14** (1.08 to 1.21)
Secondary (5–10)	0.68** (0.66 to 0.70)	0.89** (0.85 to 0.93)	1.38** (1.22 to 1.57)	1.30** (1.14 to 1.49)	1.14** (1.09 to 1.19)
University (>10)	Ref	Ref	Ref	Ref	Ref
Parity
Nulliparous	1.38** (1.34 to 1.43)	2.00** (1.88 to 2.12)	1.31** (1.18 to –1.45)	1.48** (1.33 to 1.66)	1.35** (1.30 to 1.41)
1–2	Ref	Ref	Ref	Ref	Ref
>2	0.45** (0.38 to 0.53)	0.76* (0.64 to 0.90)	1.22 (0.93 to 1.62)	1.52* (1.14 to 2.04)	1 (0.89 to 1.13)
Anaemia (g/dL)
Severe/moderate (<10)	0.87** (0.83 to 0.92)	0.89** (0.84 to 0.95)	1.43** (1.17 to 1.75)	1.67** (1.33 to 2.08)	1.26** (1.18 to 1.35)
Mild (10>11)	0.90** (0.86 to 0.94)	0.90* (0.85 to 0.96)	1.28* (1.05 to 1.57)	1.28* (1.02 to 1.60)	1.08* (1.01 to 1.15)
Normal (≥11)	Ref	Ref	Ref	Ref	Ref
Body mass index (kg/m2)
Underweight (<18.5)	0.85** (0.82 to 0.88)	0.85** (0.81 to 0.88)	1.1 (1.00 to 1.22)	1.12* (1.00 to 1.25)	1.21** (1.16 to 1.25)
Normal (18.5 to 24.9)	Ref	Ref	Ref	Ref	rRef
Overweight or obese (≥25)	1.57** (1.48 to 1.67)	1.48** (1.36 to 1.60)	0.92 (0.70 to 1.20)	1.11 (0.84 to 1.46)	0.84* (0.76 to 0.94)

*P<0.05, **p

<0.001.

†Obtained by multivariable GEE regression models for each outcome, separately.

GEE, generalised estimating equations.