Smoking trends before, during, and after pregnancy among women and their spouses.

Background: Pregnancy and childbirth can act as strong factors motivating parents to spontaneously quit smoking. The aim of the present survey was to establish smoking cessation guidelines for this group. The objectives were to clarify the smoking status of parents before, during and after pregnancy, as well as the factors associated with continuous smoking during pregnancy and post-partum smoking relapse among women who had stopped smoking during pregnancy. Methods: A cross-sectional survey with self-administered questionnaires was conducted for the parents of the 908 infants who participated in the official medical and dental examination for 18-month-old infants in Itabashi ward, Tokyo,Japan. Results: The prevalence of smoking among women before, during pregnancy, and at post-partum 18 months at 95% confidence intervals was 29.3% (23.3-35.3%), 9.8% (3.0-16.6%), and 23.1 (16.8%-29.4%), and among their spouses it was 64.3% (60.0-68.6%), 58.1% (53.4-62.7%), and 58.2% (53.5-62.8%), respectively. The positive factors associated with smoking among pregnant women were marriage to a smoker, less education, under stress, and part-time employment rather than unemployment. The positive factors associated with smoking relapse after childbirth among women were breast-feeding <6 months and age under 30 years. Conclusion: Compared with Western countries, the rate of smoking cessation during pregnancy was relatively high in Japan. It is necessary that smoking cessation intervention and support for men be initiated at the early stages of their spouses' pregnancies. These observations could influence the targeting and design of maternal smoking intervention.