Abnormal first trimester serum interleukin 18 levels are associated with a poor outcome in women with a history of recurrent miscarriage

PROBLEM: How the maternal immune system adapts to tolerate the fetus is not fully understood, but a successful pregnancy is associated with the production of Th2-type cytokines and miscarriage is associated with the production of Th1-type cytokines.METHOD OF STUDY: Levels of interferon (IFN)-gamma, interleukin (IL)-4, IL-12 and IL-18 were measured in serum from 205 pregnant women of whom 115 pregnant women had a history of recurrent miscarriage.RESULTS: Compared with healthy pregnant women those who miscarried had increased serum levels of the Th1-associated cytokines IFN-gamma, IL-12 and IL-18.CONCLUSIONS: Increased levels of IL-18 appeared to be critical in early pregnancy and were able to discriminate between pregnancies that continued and those that end in miscarriage.