Infertility is a common condition that affects 9%-18% of the general population. The causes of female infertility can be different: genetic, anatomic abnormalities, endocrine and autoimmune disorders. Women with some autoimmune disorders (systemic lupus erythematosus, antiphospholipid syndrome, and autoimmune thyroid disease) are at higher risk of infertility.
Active vitamin D can work as a positive immunomodulator on both the innate and adaptive immune responses. Vitamin D production occurs under the influence of sunlight and are best when there is sunlight exposure without burning of the skin. Insufficient level of vitamin D is prevalent by autoimmune diseases and correlates with disease activity and comobildity (the presence of one or more additional diseases).
Current cohort study found that autoimmune disorders and low vitamin D levels are both contributing to the risk for primary infertility in women. Therefore, vitamin D supplementation may be useful for improving reproductive outcomes in women suffering from primary infertility, in particular for those with coexisting autoimmune disorders.