Immunotherapy for Recurrent Pregnancy Loss

Abstract When immunomodulation is used on an unselected population with recurrent miscarriage (RM), there is no improvement the live birth rate. However, when the population is selected for a poor prognosis, or immune phenomena, immunotherapy has been shown to be effective. This review discusses four immunomodulatory agents, paternal leucocyte immunization, intravenous immunoglobulin (IVIG), intralipid and filgrastim. The presence of embryonic aneuploidy may confound the results of treatment, creating an impression of futility when treatment may be highly effective in saving those pregnancies which can be saved. Additionally, in an unselected population with RM, there is a relatively good prognosis for a subsequent live birth of 60-80% depending whether the definition of > 2 or > 3 miscarriages is used. Hence the spontaneous prognosis must be taken into account, which has not been the case in previous trials. In this review, the possible immunologically mediated mechanisms of pregnancy loss are discussed, and the means whereby immunotherapy may modulate these mechanisms.