Uc Science Today

Male fetuses may be more sensitive than females to maternal smoking, before and during a woman’s pregnancy. Chemicals in tobacco may lead to increased vulnerability of developing lymphocytes and cause genetic damage or what scientists call deletions. That’s according to a study by Adam de Smith, an associate researcher at the University of California, San Francisco. "Male fetuses grow quicker than females. So we think perhaps there could be a higher rate of turnover of immune cells in male fetuses compared with females. Those male immune cells are more prone to developing these deletions." Inflammation in mothers’ bodies during pregnancy, possibly exacerbated by tobacco smoke exposure, might also trigger genetic mutations. "It has been shown that there are differences between the inflammation that’s found in mothers carrying male fetuses compared with females. I believe it is a higher inflammation with a male fetus. So that’s another potential mechanism for increasing the number of deletions."