IRCT2013110915342N1 IRCT 2014-05-12 Avicenna Research Institute The effect of Prednisolone in reducing of recurrent abortion A randomized controlled trial of prednisolone for women with idiopathic recurrent miscarriage and raised levels of Peripheral natural killer cells . 2013-11-21 anticipated 100 Complete https://irct.ir/trial/14633 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Prevention. N/A Idiopathic Recurrent Abortion. Intervention 1: Case group are treated with prednisolone with this protocol: prednisolone 2 months before taking action to pregnancy; first week 20 mg daily; second week 15 mg daily ; third to seventh week 10 mg daily ; eighth week 5 mg daily.Then recheck NK-cell density , if there is suitable response, taking action to pregnancy will be allowed .After positive pregnancy test ,restarting prednisolone or placebo with this protocol:10mg daily until 14th week of gestational age ,when the dose will be tapered off and stopped. In addition, both of groups equally are treated with empirical treatment which have been effective in past studies of idiopathic recurrent abortion, including : ASA-FA5mg-vit B6. Intervention 2: Control group with placebo before and during pregnancy ;with this protocol: placebo 2 months before taking action to pregnancy; first week 20 mg daily; second week 15 mg daily ; third to seventh week 10 mg daily ; eighth week 5 mg daily.Then recheck NK-cell density , if there is suitable response, taking action to pregnancy will be allowed .After positive pregnancy test ,restarting placebo with this protocol:10mg daily until 14th week of gestational age ,when the dose will be tapered off and stopped. In addition, both of groups equally are treated with empirical treatment which have been effective in past studies of idiopathic recurrent abortion, including : ASA-FA5mg-vit B6.