Active and passive maternal smoking during pregnancy and birth outcomes: the Kyushu Okinawa Maternal and Child Health Study

摘要

BackgroundIn Western countries, active maternal smoking during pregnancy is recognized as the most important preventable risk factor for adverse birth outcomes. However, the effect of passive maternal smoking is less clear and has not been extensively studied. In Japan, there has been only one epidemiological study which examined the effects of active smoking during early pregnancy on birth outcomes although the effects of passive smoking were not assessed.