Provided is a highly safe composition which is to be administered to pregnant and/or breastfeeding women so as to prevent a respiratory disease in infants born to the women. The composition for preventing a respiratory disease comprises a bacterium belonging to the genus Bifidobacterium as an active ingredient. The composition is to be administered to pregnant and/or breastfeeding women so as to prevent a respiratory disease in infants born to the women. This composition is particularly suitable for lowering the risk of the respiratory disease in the infants when the women are exposed to air pollution and/or passive smoking and thus the aforesaid risk is increased.本發明的目的在於提供一種組成物，安全性高，且藉由懷孕期以及／或哺乳期的母體攝取以預防該母體所生出之嬰幼兒的呼吸器官疾病。一種呼吸器官疾病預防用組成物，係以雙岐桿菌屬細菌為有效成分，該組成物為對懷孕期以及／或哺乳期的母體投與，且用以預防該母體所生出之嬰幼兒的呼吸器官疾病。該組成物尤其適用於降低前述母體暴露於空氣污染環境下以及／或二手煙之環境下而提高之前述嬰幼兒的前述呼吸器官疾病的罹患風險。
