We all know that the risks that affect foetuses when a pregnant woman smokes are multiple: premature birth, increased risk of miscarriage... The pictogram ‘prohibited for pregnant women’ is also present on all packets of cigarettes in the UK. But perhaps the ban should be extended to prospective parents in general, as a new study shows that passive smoking could be just as damaging. Passive smoking, a scourge for the foetusResearchers from the Xiangya School of Public Health published a study in the European Journal of Preventive Cardiology that highlights the risks of passive smoking on the foetus. Indeed, the results are there; passive smoking increases the risk of congenital heart defects in the foetus.‘Dads-to-be [and expectant parents in general] should stop smoking,’ says Dr Jiabi Qin from the School of Public Health in Changsha, China, and lead author of the study. ‘Fathers are a major source of passive smoking among pregnant women, which could be even more dangerous for the unborn child than mothers who smoke.’8 out of 1000 babiesCongenital heart defects are responsible for 8 deliveries of stillborn children out of 1000. Since smoking can increase the risk of congenital heart defects, it is strongly recommended that future parents avoid smoking during pregnancy.A recent study even found that stopping smoking during pregnancy is not enough: ‘If you're a smoker, it's important to stop smoking before pregnancy,’ says Tatiana Anderson, a neuroscientist at the Institute for Research on Childhood in Seattle, ‘We found that women who smoked three months before getting pregnant and who stopped in their first trimester still had a 50% higher risk of sudden infant death syndrome compared to that of a non-smoker.’The study by Dr Jiabi Qin and his team is the first meta-analysis examining the relationships between second-parent smoking, passive smoking in the mother, and the risk of congenital heart defects in the foetus. ‘Smoking is teratogenic, which means that smoking can cause developmental malformations during pregnancy (...) Moreover, smoking in the second parent is more common than pregnant women smoking.’A risk during the entire duration of pregnancyThe results of the study are very clear, passive smoking is dangerous in women during the entire pregnancy. But in everyday life avoiding cigarette smoke in the street, on the terrace or at a friend’s is not always easy.