Association between house renovation during pregnancy and wheezing in the first year of life: The Japan environment and children's study

Background: Wheezing is a common symptom in infants, which may occasionally develop into asthma. There are many factors related to infant wheezing, including anatomical features, viral infections, and passive smoking. There are only a few reports on the association between renovation and pregnancy worldwide, and reports on this association are inadequate in Japan. This study aimed to examine the association between house renovation and new construction during pregnancy and wheezing in infants during the first year of life using data from the Japan Environment and Children's Study (JECS). Methods: Data of pregnant women registered in JECS were collected using self-administered questionnaires during the second/third trimester and 1 month after delivery. Childbirth records were completed by the doctors. Similarly, wheezing in infants was evaluated using self-administered questionnaires 1 year after birth. Logistic regression analysis was used to determine the primary outcome. Results: In total, 75,731 infants, excluding those with unknown gender, who were not singleton infants, and who relocated during pregnancy and the first month of life, were examined in this study. Renovation during pregnancy increased the prevalence of wheezing (odds ratio [OR]: 1.33, 95% confidence interval [CI]: 1.20–1.48) and recurrent wheezing (OR: 1.22, 95% CI: 1.00–1.48) in the first year of life. The relationship between new construction during pregnancy and wheezing in infants was insignificant (OR: 0.98, 95% CI: 0.90–1.06). Conclusions: Renovation during pregnancy may be a risk factor for wheezing in infants, and should be avoided.