Immunological factor

 

Dysregulation of the immune system and increased production of autoantibodies have been postulated to be responsible for unexplained subfertility. Auto-immune antibodies like anti-thyroid, anti-ovarian, antinuclear, antiphospholipid and anti-smooth muscle antibodies have been associated with unexplained subfertility [Ref]. While the exact role of these autoantibodies in the pathogenesis of unexplained subfertility is unclear, various theories are put forward such as reducing fertilisation rate, interfering with early implantation and modulating the function of FSH and thereby influencing ovarian function, [Ref]. In addition to the altered immune response, there are suggestions that thrombophilic gene polymorphism like MTHFR (Methylene Tetra HydroFolate Reductase) gene polymorphism could be a cause for unexplained subfertility[Ref]. Again the possible mechanism could be by causing early implantation failure, however, more evidence is needed to confirm[Ref].​