* Adjusted for infant sheepskin use at one month, exclusive breastfeeding at one month, whether infant exposed to active smoking in the same room, and synthetic pillow use in childhood.

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Synthetic pillow use at 1 month of age was strongly associated with night wheeze or frequent wheeze at age 7 but not moderate wheeze. The association persisted after adjustment for more than twenty potential confounders, including cohort entry criteria. The proportion of children with night wheeze at age seven varied by amount of synthetic bedding (nil, pillow only, quilt only, both, p=0.006).