Crude and adjusted risks of obstetric complications in the different BMI groups compared to normal (OR 1)
Characteristics
 
OR (95% CI)
 
Underweight
BMI < 20
n = 2842
 
Overweight
BM I= 2529.9
n = 5308
 
Obese
BMI = 3034.9
n = 1858
 
Morbidly Obese
BMI > 35
n = 157
 

Pre-eclampsia*
 
Crude
 
0.7(0.50.8)
 
1.7(1.41.9)
 
3.3(2.73.9)
 
7.4(4.811.5)
 

 
Adjusted
 
0.6(0.50.7)
 
1.6(1.21.8)
 
3.1(2.83.5)
 
7.2(4.711.2)
 
Gestational hypertension*
 
Crude
 
0.6(0.50.7)
 
1.6(1.51.8)
 
2.4(2.22.7)
 
3.0(2.14.2)
 

 
Adjusted
 
07(0.60.8)
 
1.5(1.41.7)
 
2.2(2.12.6)
 
3.1(2.04.3)
 
Induced labour*
 
Crude
 
0.8(0.70.9)
 
1.3(1.21.4)
 
2.0(1.82.2)
 
2.6(1.93.5)
 

 
Adjusted
 
0.8(0.80.9)
 
1.3(1.21.4)
 
1.8(1.62.0)
 
1.8(1.32.5)
 
Elective C-section
 
Crude
 
0.7(0.60.9)*
 
1.2(1.01.4)
 
1.4(1.11.8)*
 
3.2(1.95.3)*
 

 
Adjusted
 
0.8(0.61.0)
 
1.1(0.91.3)
 
1.4(1.01.8)
 
3.1(1.76.1)*
 
Emergency CS
 
Crude
 
0.9(0.91.0)
 
1.7(1.51.8)*
 
2.4(2.12.7)*
 
3.2(2.34.5)*
 

 
Adjusted
 
0.9(0.81.1)
 
1.5(1.31.6)*
 
2.0(1.82.3)*
 
2.8(2.03.9)*
 
Postpartum hge
 
Crude
 
0.7(0.60.8)*
 
1.4(1.31.6)*
 
2.3(2.12.6)*
 
2.9(2.04.2)*
 

 
Adjusted
 
0.8(0.71.0)
 
1.1(1.01.2)
 
1.5(1.31.7)*
 
1.3(0.81.9)
 
Preterm delivery (< 37 weeks)
 
Crude
 
1.1(0.91.3)
 
1.0(0.91.1)
 
1.2(1.11.4)*
 
2.1(1.43.1)*
 

 
Adjusted
 
1.0(0.91.3)
 
1.0(0.91.1)
 
1.2(1.01.4)
 
1.6(1.02.7)
 
Preterm delivery (< 33 weeks)
 
Crude
 
0.9(0.71.2)
 
1.0(0.81.2)
 
1.8(1.42.3)*
 
2.8(1.45.4)*
 

 
Adjusted
 
0.9(0.71.1)
 
1.0(0.81.1)
 
2.0(1.32.9)*
 
2.0(0.84.9)
 
Spont. Preterm (< 37 weeks)
 
Crude
 
1.4(1.11.9)
 
0.8(0.61.0)
 
0.9(0.51.1)
 
1.3(1.12.8)
 

 
Adjusted
 
1.4(1.11.9)
 
0.8(0.61.1)
 
1.0(0.51.2)
 
1.2(1.12.8)
 
Post term (> 41 weeks)
 
Crude
 
0.7(0.60.8)*
 
1.2(1.11.3)*
 
1.4(1.11.6)*
 
0.8 (0.41.7)
 

 
Adjusted
 
0.9(0.71.1)
 
0.9(0.81.1)
 
0.9(0.71.1)
 
0.8(0.41.8)
 
Stillbirth
 
Crude
 
0.8(0.51.3)
 
1.2(0.91.6)
 
2.0(1.43.0)
 
2.8(1.07.6)
 

 
Adjusted
 
1.0(0.61.6)
 
1.3(0.91.9)
 
1.8 (1.12.9)*
 
1.1(0.34.1)
 
Birth weight < 2500 g
 
Crude
 
1.4(1.21.6)*
 
0.9(0.71.0)
 
1.1(0.91.3)
 
1.8(1.13.0)*
 

 
Adjusted
 
1.7(1.22.0)*
 
0.9(0.71.1)
 
1.1(0.91.3)
 
0.7(0.41.5)
 
Birth weight > 4000 g*
 
Crude
 
0.4(0.40.6)
 
1.4(1.31.6)
 
1.9(1.72.2)
 
2.3(1.53.5)
 

 
Adjusted
 
0.5(0.40.6)
 
1.4(1.31.6)
 
1.9(1.62.2)
 
2.1(1.33.2)
 

*P value less than 0.05

All variables adjusted for relevant sociodemographic characteristics and year of delivery; induced labour, preterm delivery and caesarean section also adjusted for pre-eclampsia and gestational hypertension; postpartum haemorrhage for induction of labour and caesarean section; birthweight for gestational age and sex

Bhattacharya et al. BMC Public Health 2007 7:168   doi:10.1186/1471-2458-7-168. http://www.biomedcentral.com/1471-2458/7/168

2007 Bhattacharya et al; licensee BioMed Central Ltd.
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