Women who smoke during pregnancy may affect their future grandchildren's health

Women who smoke while pregnant may not only cause health problems for their children – but also their children’s children. Research suggests the dangers can spill down the generations, with a smoker’s grandchildren also more likely to suffer from asthma. Experts believe the harm caused by smoking in pregnancy can ‘switch on’ bad genes, which are then passed on. During pregnancy, nicotine can affect a baby’s developing lungs, predisposing the infant to childhood asthma. Although this risk is well-known, researchers from Harbor-UCLA Medical Center in California in the US wanted to investigate the implications for future generations. They tested the effect of nicotine exposure during pregnancy on rats, looking not only at their pups, named F1, but also at second generation pups, F2. The researchers found exposure inside the womb resulted in F1 offspring having reduced lung function consistent with asthma. However, it also impaired lung function of F1’s offspring F2, even though the F1 rats were not exposed to nicotine once they were born. A gene function associated with normal lung development was also reduced in both generations of offspring, says a report published in the journal BMC Medicine. Dr Virender Rehan, who led the study, said: ‘When we looked at the effect of nicotine on DNA in the testes or ovaries of the rats they found that nicotine increased the level of methylation in the testes but reduced it in the ovaries. ‘Nicotine also altered methylation of histone proteins in a sex-dependent manner. ‘These epigenetic marks may be the mechanism behind how nicotine-induced asthma is transmitted from one generation to the next.’ He said asthma is the most common chronic disease of childhood and while there are many factors which contribute to asthma, maternal smoking during pregnancy is an avoidable risk. ‘The effects of smoking during pregnancy are, it seems very long lasting’ he added. ‘Stop smoking education and intervention aimed at mothers-to-be and women planning pregnancy needs to take into account the fact that nicotine itself contains dangers to their children and their children’s children.’ Article: 30th October 2012 www.dailymail.co.uk