Table 2

Crude association of birth weight with environmental and occupational exposures and maternal and infant characteristics

Variable n Estimated2-150change in birth weight p Value (95% CI)
Maternal characteristics:
 Age (y):
  26–29526210.559(−50 to 91)
  30–401021670.001(68 to 266)
 Height tertile before pregnancy (cm):
  1st (147–159)244Referent
  2nd (160–163)314240.478(−43 to 92)
  3rd (164–180)2341120.003(40 to 184)
 BMI tertile before pregnancy (kg/m2):
  1 (14.17–20.31)264Referent
  2 (20.32–23.42)260640.068(−5 to 133)
  3 (23.43–37.46)2681000.004(31 to 168)
 College education or above250890.004(28 to 149)
 Passive smoking457−530.066(−109 to 4)
Infant characteristics:
 Parity (one or more)32830.257(−60 to 25)
 Female baby386−970.001(−153 to −40)
Occupational exposures:
 Exposure to benzene354−580.044(−115 to −2)
 Perceived work stress142−840.026(−158 to −10)
 Noise at work207−360.275(−100 to 29)
 Physical exertion194−320.337(−98 to 33)
 Other hazards108−300.471(−112 to 52)
 Work mainly in a sitting posture495180.552(−41 to 76)
  • 2-150 All the estimates were derived from a linear regression model with adjustment for a linear and a square terms of gestational age.