This prospective comparative, controlled clinical study is conducted at Department of Obstetrics and Gynecology, Benha University Hospital, and a private center, from June 2012 . After approval of the study protocol by the Local Ethical Committee and obtaining written fully informed patients' consents. All patients are interviewed about their medical, personal, family, obstetrical and thrombosis history. All patients included in study complain of three or more unexplained consecutive spontaneous abortions.