Intravenous immunoglobulin and recurrent pregnancy loss.

Intravenous immunoglobulin (IVIg) has been used to prevent pregnancy loss, in unexplained recurrent miscarriage, and in antiphospholipid syndrome (APS). When used on an unselected population with recurrent miscarriage, IVIg has not been shown to improve the live birth rate. However, when patients are selected for poor prognosis or autoimmune phenomena, IVIg has been shown to be effective. This article discusses the possible immune mechanisms by which IVIg may act and the effect of confounding factors such as embryonic chromosomal aberrations or anti-beta2-glycoprotein I antibodies in APS. Hence, there may be an impression of futility, when IVIg may be highly effective in saving those pregnancies that can be saved. Additionally, in an unselected population with recurrent miscarriage, there is a relatively good prognosis for a subsequent live birth (60%). Therefore, the spontaneous prognosis must be taken into account, which has not been the case in previous trials.