TY - JOUR AB - Recurrent pregnancy loss (RPL) is usually characterized as ≥3 miscarriages before 20 weeks of gestation. Patients with RPL may have autoimmune abnormalities or alloimmune problems. Vitamin D has a major function on the mechanism of immunomodulation at the maternal‑fetal interface. However, whether vitamin D can be used as an effective method to treat patients with RPL requires investigation. It has been reported that vitamin D could prevent the occurrence of antiphospholipid syndrome (APS) by reducing the expression levels of anti‑β2 glycoprotein and tissue factor in RPL cases with APS. In addition, there is an opposite relationship between vitamin D and thyroid peroxidase antibody levels in autoimmune thyroid disease cases with RPL. Vitamin D changes the ratio of T helper (Th) 1/Th2 and regulatory T cell/Th17 to a certain extent, as well as affects the activity of natural killer cells and the production of cytokines to reduce the incidence of RPL. The objective of the current review was to address the research progress of vitamin D in RPL in recent years, which could facilitate the use of vitamin D treatment to enhance the pregnancy outcome of RPL. Collectively, it was suggested that vitamin D may be used as an important and effective immunotherapeutic agent for patients with RPL. AD - Department of Hepatobiliary Surgery and Organ Transplant, The First Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China Department of Obstetrics, The First Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China AU - Zhao,Haoyu AU - Wei,Xiaoqi AU - Yang,Xiuhua DA - 2021/05/01 DO - 10.3892/mmr.2021.12021 IS - 5 JO - Mol Med Rep KW - vitamin D RPL autoimmunity cellular immunity NK cells PY - 2021 SN - 1791-2997 1791-3004 SP - 382 ST - A novel update on vitamin D in recurrent pregnancy loss (Review) T2 - Molecular Medicine Reports TI - A novel update on vitamin D in recurrent pregnancy loss (Review) UR - https://doi.org/10.3892/mmr.2021.12021 VL - 23 ER -