Abstract

Cellular and molecular processes and pathways responsible for successful pregnancy development and maintenance are still mysterious and unknowable clearly. Poor development can cause defects in placentation and fetal outcome, so understanding molecular and cellular mechanisms leading to successful pregnancies can help in the development of a newer intervention to prevent pregnancy complications like preeclampsia, intrauterine growth restriction, pregnancy loss, and premature delivery. All through the pregnancy, the mother’s immune system should actively adapt to the fetal antigens. The frequency of various immune cells in the maternal-fetal interface changes during pregnancy to maintain and support good pregnancy outcomes. How body responds to infections in pregnancy, immunological reasons of the severity of infections in pregnancy and fetal response to infections is discussed in this review along with the involvement and interactions of various immune cells in pregnancy like Nk cells, macrophages, dendritic cells, T cells, Th17 cells, T regulatory cells and B cells.