Having a gas stove, mildew or mold, or water damage in the home during pregnancy was not associated with shorter pregnancy duration or lower birth weight, according to a recent ECHO Cohort study led by Deborah Bennet, PhD, and Jiwon Oh, PhD, of University of California, Davis.

While outdoor air pollution has been linked to adverse birth outcomes such as preterm birth and low birth weight, less is known about the effects of common indoor household exposures during pregnancy such as gas stoves, mold or mildew, and water damage. These exposures can contribute to indoor air pollution or damp conditions that may affect maternal and fetal health.

Overall, the results of this study found no strong overall link between these household exposures and outcomes like preterm birth or birth weight, when looking at the full study population. Using kitchen ventilation, such as a hood or fan, also did not appear to change these results.

However, some differences were seen in certain groups. For example, mold or mildew and water damage were linked to a higher likelihood of early term birth (37-38 weeks) in homes built after 1980, and mold exposure was associated with a higher chance of preterm birth among mothers with higher education. Other patterns varied by race and ethnicity.

These findings suggest that indoor air quality during pregnancy may not have a strong association with birth outcomes overall, but that housing and social factors may influence how these exposures affect health.

“Although the presence of gas stoves, mold, or water damage in the home during pregnancy was not associated with adverse birth outcomes in this population-based study, frequent ventilation through windows or doors is recommended to reduce exposure to potentially harmful indoor air pollutants,” said Dr. Bennett.

Researchers say future studies could provide more details about indoor conditions, including how often gas stoves are used, how well homes are ventilated, and how severe mold or water damage may be.

This collaborative research, titled “Prenatal Exposure to Gas Stoves, Mold, and Water Damage: Associations With Gestational Duration and Fetal Growth in the ECHO Cohort,” is published in Environmental Pollution.