A woman’s exposure to nicotine while pregnant may cause asthma in her great-grandchildren, according to researchers from Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center (LA BioMed), who demonstrated the transgenerational transmission of the asthma phenotype to F3 offspring following perinatal nicotine exposure.

“Even though there are multiple causes for childhood asthma, research linking this serious chronic condition to maternal nicotine exposure during pregnancy for up to three generations should give mothers-to-be even more reasons to reconsider smoking,” said Virender K. Rehan, MD, an LA BioMed lead researcher and the corresponding author of the study. “Eliminating the use of tobacco during pregnancy could help halt the rise in childhood asthma and ensure healthier children for generations to come.”

Previous research linked nicotine exposure to asthma in the second generation, according to the authors. Nicotine was affecting both the lung cells and the sex cells in ways that caused the lungs that developed from those cells to develop abnormally, causing asthma. The current study “paves the way for determining the epigenetic mechanisms” behind smoking and the transmission of asthma to future generations, they concluded.