Smoking before pregnancy or while breastfeeding may substantially decrease the fertility of female offspring, according to mouse studies conducted at the University of Toronto in Ontario, Canada (Jurisicova A et al. J Clin Oncol. doi: [published online ahead of print on November 21, 2007]).
Investigators discovered that female mice injected under the skin with polycyclic aromatic hydrocarbons—environmental toxins found in cigarette smoke—before pregnancy or while lactating gave birth to female offspring with ovaries that had reduced numbers of egg-containing follicles.
When the researchers analyzed the mechanisms involved, they found that these effects were mediated through a protein called the aryl hydrocarbon receptor. Activation of this receptor causes increased expression of the gene Harakiri, which is involved in mediating apoptosis, or cell death.
Because polycyclic aromatic hydrocarbons also triggered similar molecular pathways in human ovarian tissue transplanted into mice, the authors raised concern about the transgenerational . . . [Full Text of this Article]
