RESUMO
PROBLEM: Paternal leukocyte immunotherapy has been used as treatment for spontaneous recurrent miscarriage; however, controversies have raged against the factors influencing its success. METHODS: Five hundred and forty-nine women with three or more unexplained pregnancy losses were offered immunization. Two weeks after the second immunization, serum was tested for anti-paternal cytotoxic antibody (APCA) by cross matching and if revealed positive she was advised pregnancy. Meanwhile, decision trees have been developed by Waikato Environment for Knowledge Analysis package to predict factors influencing APCA production and pregnancy. RESULTS: Of 549 subjects, 93 (16.9%) revealed to have positive APCA, among whom 49(52.7%) had clinically successful pregnancy (> or =28 weeks). Patient's age, consanguinity between couples and previous history of surgery, and infectious, endocrine, immunologic, uterine and cervix disorders were inversely associated with APCA production and clinically successful pregnancy, whilst, number of children was a potent positive predictor. CONCLUSION: Leukocyte immunization could be borne in mind as a therapeutic approach in selected subjects. Younger females with negative past medical history who are not frequent aborters are more likely to take benefit from this therapeutic approach if they do not have any familial relationship with their spouse.