Flow cytometric crossmatch and early pregnancy loss in women with a history of recurrent spontaneous abortions who underwent paternal leukocyte immunotherapy

OBJECTIVE: The purpose of our study was to evaluate the clinical significance of flow cytometric crossmatch in managing women with unexplained recurrent spontaneous abortions who have been immunized with paternal leukocytes. STUDY DESIGN: Two-color flow cytometric crossmatch was performed after immunotherapy in 69 women with recurrent spontaneous abortions to detect maternal immunoglobulin G antibodies against paternal T lymphocytes. A positive flow cytometric crossmatch was determined by a ≥ 20 channel increases (256 channel linear scale-log amplification) in the fluorescence intensity of the T-cell peak. We analyzed the clinical correlation between flow cytometric crossmatch results and subsequent pregnancy outcome in those patients using the Fisher exact test. RESULTS: In 46 subsequent pregnancies among 69 immunized women the incidence of early subsequent pregnancy wastage was only 6 (17.1%) of 35 in flow cytometric crossmatch-positive patients and 7 (63.6%) of 11 in flow cytometric crossmatch-negative patients (p < 0.01). CONCLUSIONS: These data indicate that a two-color T cell flow cytometric crossmatch predicts subsequent pregnancy outcome in patients undergoing immunotherapy for recurrent spontaneous abortion.