Cigarette smoking during pregnancy and mother's occupation.

The association between mother's occupation and cigarette smoking prevalence during pregnancy was analyzed in over 350,000 Washington State births during the years 1984 through 1988. Smoking prevalence during pregnancy varied markedly by maternal age, race, marital status, and social class, with higher smoking rates found in unmarried women, women 25 through 29 years old, native Americans and whites, and women in low socioeconomic classes. Women who worked in traditionally male occupations or in occupations where alcohol was served had the highest smoking rates. Occupational groups with exposure to toxic or carcinogenic substances (including second-hand smoke) also had elevated smoking rates. These data could be useful in planning intervention strategies, in studies of occupational morbidity and mortality, and in analysis of the reproductive effects of maternal occupational exposures.