Feto-Maternal Cell Trafficking and Labor

Maternal-fetal cellular trafficking is a complex process in which fetal cells migrate into the maternal circulation and maternal cells migrate into the fetal circulation. This phenomenon can result in long-lived microchimerism within the mother and her progeny. Recently, examination of the levels of trafficking between the mother and fetus has gained momentum with improvements in strategies to detect microchimerism. The long-term consequences of trafficking have been explored in the context of transplant tolerance and autoimmunity. In addition to long-term effects, trafficking may also lead to pregnancy complications, such as preeclampsia, intrauterine growth restriction, and preterm labor, which are the leading causes of morbidity and mortality during pregnancy. Fetal surgery, a strategy that has improved survival in many fetuses with severe congenital anomalies, may enhance cellular trafficking and is often accompanied by pregnancy complications. However, the connection between the two entities remains unknown. In this chapter, we will review current techniques to detect fetal and maternal microchimerism and implications of microchimerism as it relates to maternal and fetal/child health, with a particular emphasis on pregnancy complications. Finally, we will explore the effects congenital abnormalities and fetal surgery on maternal-fetal cellular trafficking.