The Effect of Parental Smoking and Industrial Pollution on Birth Weight

Summary

The effect of maternal and paternal smoking on birth weight was studied in a birth cohort of 9478 children born in a geographically defined area in Northern Finland in 1985–1986. Data were collected in a prospective manner and included 99% of all births in the study area during one year. Some 22.3% of the mothers and 36.5% of the fathers smoked, and in 42.8% of the cases at least one parent smoked. The effect of maternal and paternal smoking on birth weight was studied by analysis of covariance employing 43 confounding variables. Maternal smoking had a highly significant effect, but paternal smoking had no significant effect. The effect of environmental pollution was studied by the same method in a subgroup of 2086 cohort families living in the city of Oulu and its surroundings. Environmental pollution did not affect birth weight either alone or in combination with parental smoking. The effect of paternal smoking on low birth weight, less than 2,500 g, rate was studied also separately among the full-term infants, and after adusting 57 confounding factors it had no statistically significant effect.