According to new research presented at the World Cancer Congress in Melbourne, Australia, researchers at the University of Tromsø in Norway have found that about 9% of breast cancer cases in mothers can be averted if women do not smoke cigarettes prior to the birth of their first child.
For the study, researchers identified 137,412 Norwegian women between the ages of 34 and 70. Of those, 90% were mothers. Women were followed for 12 years and results showed that 3,157 of them developed breast cancer. The researchers found that one in 11 of these breast cancer cases could have been prevented had these women not started smoking prior to the birth of their first child.
Breast tissue does not mature completely until after a woman had given birth and breast-fed, so smoking prior to giving birth leaves immature breast cancer more susceptible to carcinogens from cigarette smoke.
In 2014, the U.S. Surgeon General published a report that there is not sufficient evidence to conclude that tobacco smoke causes breast cancer. Around the world, women are smoking tobacco more and more younger women are smoking daily.
Research presented yesterday at the World Cancer Congress shows that one in eleven breast cancer cases in mothers can be prevented if women do not smoke before having their first child.