Pathological changes in products of conception of aborters with deficient immunologic block factor [s]

The study was performed on 20 aborters 13 of which were seronegative in the blocking factor. The pathological changes especially vasculitis, cellular infiliterate of lymphocytes, histiocytes as well as fibrosis of chorionic villi were more frequent and more marked in these seronegative cases than in seropostive ones. The possible role of absence of blocking factor in production of this changes and hence termination of pregnancy was discussed