PARTNERS SMOKING - A MAJOR DETERMINANT FOR CHANGES IN WOMENS SMOKING-BEHAVIOR DURING AND AFTER PREGNANCY

To study determinants for changes in maternal smoking behaviour during and after pregnancy, questionnaire information on smoking habits was recorded in a cohort of 3710 Norwegian women during early pregnancy, a t delivery, and one year later. Of 3039 cohabiting women with complete information on smoking at all three occasions 31% smoked in early pre gnancy 23% in late pregnancy and 28% one year after delivery. Among th e cohabiting mothers who smoked in early pregnancy, 44% stopped during pregnancy. After adjusting for confounding factors, the odds ratio fo r smoking cessation among these women who had cohabitants who smoked a s opposed to not smoking was 0.2 (95% CI: 0.1-0.2). Among cohabiting n on-smoking women during late pregnancy the odds ratio for being a smok er one year after child birth was 3.0 (95% CI: 2.2-4.0), if their coha bitants smoked as opposed to not smoking. The women's smoking behaviou r changes considerably during and after pregnancy and their cohabitant s' smoking seems to be a major determinant for changes in their smokin g behaviour.