Researchers at Warwick Medical School have discovered that recurrent pregnancy loss can be due to a dysfunctional monthly fertility window, raising hope new treatments can be developed to help women who suffer from repeated miscarriages.

Usually, the release of certain cytokine and activation of its receptor in cells in the uterus induces an inflammatory response, which controls the stage that we are familiar with as the two to three days of peak fertility, or the fertility window.

But work at the Clinical Sciences Research Laboratories at Warwick Medical School showed clearly that in patients with a record of recurrent pregnancy loss, this inflammatory response was prolonged. When the fertility window remains open too long, embryos implant out-of-phase into an environment that cannot support the pregnancy, which leads to miscarriage.

The discovery means intervention targeting the related cytokine and receptor in the uterus may help prevent miscarriages by regulating the fertility window, researchers say.