The Role of Cytokines and Immune System in Unexplained Infertility

Abstract

Many factors contribute to infertility, including immune conditions which may lead to immune infertility (immunologic infertility). The aim of this review is to evaluate the peer-reviewed studies reported so far regarding the immune cell sub-populations of T helper (Th) 1, Th2, and Th17 cells, regulatory T cells (Tregs), and cytokines produced by these cells, and their possible interplay in relation to unexplained infertility and to provide a potentially new diagnostic approach to immunologic infertility by investigating the correlation of Th1, Th2, Th17, and Treg and their secreted cytokines. Because the association of the immune system with almost all pathologies is relatively new, albeit remarkable, which opens to research and exciting development, hence we aimed to write this review article. Moreover, this review focuses on the potential roles of cytokines during pregnancy, which we believe will contribute to the understanding of the roles and mechanisms behind the cytokines that affect physiological and pathological conditions during pregnancy.