Childhood asthma risk is affected not only by mother’s smoking, but by in utero exposure to grandmother’s smoking. A recent longitudinal study was performed to evaluate effects of grandmother’s smoking on childhood asthma risk. It looked at 966 cases of asthma and 5,915 controls without asthma.
Prenatal exposure of the mother to cigarette smoke did not affect the grandchildren’s risk of being diagnosed with asthma. However, paternal prenatal exposure to their own mother’s smoking was associated with increased risk of persistent wheezing in the daughters of those fathers.
While these results are interesting, the author caution that the results are based on reported symptoms without corroborating biologic evidence.