Abstract
Evidence of bidirectional cell traffic between fetal and maternal departments is well established in pregnancy. The amount of cell traffic varies, however, with mode of delivery. Maternal–fetal traffic is highest with vaginal and lowest with cesarean section delivery. Fetal–maternal cell traffic follows opposite dynamics. Cell traffic has the potential to establish microchimerism of donor cells within the recipient. The presence of such microchimerism in recipients of cell traffic has been associated by some investigators with the occurrence of autoimmune diseases. Since this association between cell traffic, microchimerism and the development of autoimmune diseases has remained unproven, this article proposes that, if microchimerism is causally connected to the occurrence of autoimmune diseases, the prevalence of autoimmune diseases in offspring should correlate with their mode of delivery. The design of appropriate population studies would seem to be urgent because confirmation of this hypothesis would establish the mode of delivery as a controlling therapeutic modality in preventing autoimmune diseases in offspring.