Abnormal cytokine levels in non-pregnant women with a history of recurrent miscarriage

OBJECTIVE: To compare cytokine levels in serum from non-pregnant women with a history of recurrent miscarriage with those found in non-pregnant women with no such history. STUDY DESIGN: Two patient groups were enrolled into the study. Group 1 comprised 25 non-pregnant women with no history of recurrent miscarriage. Group 2 comprised 50 non-pregnant women who had a history of at least three previous miscarriages. Fifteen of these women have since become pregnant again--10 had a successful pregnancy and five miscarried. Serum levels of IL-4, IFN gamma, IL-12 and IL-18 were measured. RESULTS: Results showed IFN gamma ( 0.68 +/- 0.72 versus 0.45 +/- 0.29 P < 0.05) and IL-12 levels (66 +/- 25 versus 51 +/- 24 P < 0.05) were significantly higher in Group 2 compared to Group 1. Levels of IL-18 were significantly lower in Group 2 patients (318 +/- 140 versus 246 +/- 219 P < 0.05). Of the 15 women who became pregnant, those who miscarried again had significantly higher IL-18 levels when not pregnant than those women whose next pregnancies went successfully to term (547 +/- 20 versus 274 +/- 129 P < 0.05). CONCLUSION: These results suggest that women with a history of recurrent miscarriage can have abnormal cytokine expression even when not pregnant. This may influence the potential for future successful immune modulatory therapy.