Table 2 Multivariate analysis of risk factors associated with Birth defects (n=66,123)

 20-< 35 years

Reference

 < 20 years

1.64 (1.18–2.28)

0.003

 > 35 years

0.94 (0.57–1.54)

0.79

 Brahmin/Chhetri (relatively advantaged group)

Reference

 Others (relatively disadvantaged group)

1.78 (1.46–2.18)

< 0.001

 Clean

 Polluted

2.26 (1.80–2.84)

< 0.001

 Boy

Reference

 Girl

1.35 (1.13–1.61)

0.001

 Nullipara

Reference

 Primipara

1.58 (1.26–1.98)

< 0.001

 Multipara

2.33 (1.84–2.95)

< 0.001

 No

Reference

 Yes

1.80 (0.98–3.28)

0.06

Constant

0.002

< 0.001