Oral corticosteroids in treatment of unexplained recurrent pregnancy loss; Rationale for administration in the PREMI trial.

Unexplained recurrent pregnancy loss affects many fertile couples who want to conceive. Possibly, the maternal immune system is involved in the underlying mechanism of such unexplained cases and immune-suppressing corticosteroids can be used to modulate this system and improve pregnancy outcome. As a high quality, sufficiently powered randomized controlled trials in the unselected unexplained RPL population is currently lacking, the PREMI (Prednisolone administration in patients with unexplained REcurrent Miscarriages) trial was designed. Here, we discuss the rationale for the administration of prednisolone, including its potential mechanisms, safety, administration protocol and study population.