Prevention of recurrent spontaneous abortions by leukocyte transfusions.

One hundred and thirty-nine couples referred because of recurrent abortions with no obvious cause were assessed for genetic similarity using the HLA major histocompatibility system. Comparison with 103 fertile control couples demonstrated that a much higher proportion of couples in the abortion group shared two or more HLA antigens. Using this criterion, 44 wives out of the 139 couples referred, when compared with a child-bearing group, appeared to share a greater than expected number of histocompatibility antigens and were therefore considered suitable for treatment. Twenty-eight wives have received treatment with white cell infusions from erythrocyte-compatible donors and so far they have delivered 17 babies plus 2 second babies. Another 3 wives are pregnant beyond their previous dates for abortions (1 first and 2 second pregnancies). There have been 5 failures (4 first pregnancy and 1 second pregnancy); one of these was treated a second time and has now successfully delivered. Seven couples are awaiting conception. Of the patients who have become pregnant, 81.5% have had successful deliveries. No adverse transfusion reactions have been observed.