How long Japanese mothers quit smoking when they start raising children? New evidences from a very large national data

Background: The exposure of children to secondhand smoke at home and elsewhere has been largely an overlooked problem in Japan, regardless of widely well spread knowledge about health risk of secondhand smoke exposure to children. Furthermore, evidence and study are limited and little is known about relationship between smoking behavior and socio-economic factors in Japan. Objectives: Our broad perspective is to identify the important risk factors of women’s smoking. We first focus on mother who has greater impact on child health. Thus, our main interest here is to demonstrate mothers’ behavior during the course of one year after child birth. We also address association between women’s smoking behavior from several different point of views including their characteristic, family or social environments. Methods: The four different years (2001, 2004, 2007, 2010) of Comprehensive Survey of Living Conditions, a nationally representative data, are used. Multivariate logistic regression is conducted as setting one for smoking and zero for non-smoking. Followed by this, marginal effects of each variable are estimated. Results: Mothers cessation of smoking after delivery is unstable in Japan, depending on the age and the parity of a child. For a first child, more than two-thirds of women who used to smoke, abstain from smoking at least for one year. For a second child, compared with a first child, only a half of the mothers quits temporarily in its first year. In both cases, cessation efforts decline rapidly over time. By the time a mother has a third child, she barely quits smoking. Although an increasing proportion of mothers are quitting in the first year, the difference narrows considerably in subsequent years. We also found that, among Japanese women, such factors as marital status, husband’s smoking status, other smokers in household are strongly related to smoking, while job-types, living with head of household’s parents, and housing have differential impacts on it.