Table 3

Mean differences and 95% CIs between anthropometric measurements at birth in infants whose mothers quit or reduced smoking compared with infants whose mothers did not change their cigarette consumption after the first trimester

No change in cigarette consumption (n=24)Reduced cigarette consumption (n=145)Quit after first trimester (n=50)Non-smoker (n=927)
Mean difference in birth weight (g)0104 (−73 to 282), p=0.250246 (46 to 445), p=0.012290 (115 to 463), p=0.001
Mean difference in crown–heel length (cm)00.65 (−0.11 to 1.40), p=0.0921.14 (0.29 to 1.99), p=0.0201.37 (0.63 to 2.11), p<0.001
Mean difference in occipitofrontal circumference (cm)00.08 (−0.42 to 0.58), p=0.7460.39 (−0.17 to 0.95), p=0.1700.44 (−0.52 to 0.92), p=0.080
  • Analysis adjusted for sex, maternal height, maternal plasma α-tocopherol, maternal plasma cholesterol, paternal smoking, gestation at birth and Scottish Index of Multiple Deprivation.