Interdisciplinary exchange of ideas: progestagens for autoimmunity, biologics for pregnancy complications.

In recent years, there has been a growing interest in the role of immune, alloimmune and autoimmune processes in the pathogenesis of spontaneous preterm birth and recurrent pregnancy loss. The association between an inflammatory response and preterm labor has been established. Indeed, many women suffering from preterm labor have elevated inflammatory markers such as tumor necrosis factor alpha, interleukin 6 and matrix metaloproeinase 8. The role of immune processes in the pathogenesis of recurrent pregnancy loss has also been widely researched. Progesterone induces many physiologic effects necessary for healthy pregnancy, and progestagens supplementation has been used as an approach to prevent preterm labor and recurrent pregnancy loss. Progestagens also have potent anti-inflammatory and immunomodulatory actions. Because preterm labor and recurrent pregnancy loss are associated with abnormal inflammation, progestagens may maintain healthy pregnancy through both endocrine and immunologic actions. These immunologic actions, such as suppression of Th1- and Th17-related responses, enhancement of regulatory T cell (Tregs) activity and suppression of inflammation, may also be involved in pregnancy-induced remission of certain autoimmune diseases such as rheumatoid arthritis (RA) and multiple sclerosis (MS). Accordingly, there is growing interest in the potential therapeutic role of progestagens in the treatment of MS and RA. In this review, we suggest that biologic autoimmune modulators, especially those which affect immune pathways similar to progestagens, may provide more potent and specific effects, and hence better results than progestagens, in preventing preterm labor and recurrent pregnancy loss.