Air pollution and birth weight in Britain in 1946

Recent studies suggested that air pollution might be related to Low birth w eight. We tested this hypothesis on data from the British 1946 birth cohort . We found a strong association between birth weight and an air pollution i ndex based on coal consumption. Babies born in the must polluted areas were on average 87 grams lighter than those born in the areas with the cleanest air. Adjustment for a number of sociodemographic factors did not change th ese estimates. While confounding by unmeasured factors cannot be ruled out, these historical data support the hypothesis that birth weight could be af fected by air pollution.