NK cell activity and subsets in women with a history of spontaneous abortion. Cause, number of abortions, and subsequent pregnancy outcome

Abstract

Objective: The aim of this study was to assess the role of NK cells in nonpregnant women with a history of spontaneous abortion.

Study design: 113 nonpregnant women with a history of spontaneous abortion were assessed for peripheral NK cell activity and percentage of NK cell subsets, in relation to the cause of abortions, the number of spontaneous abortions, and subsequent pregnancy outcome (n = 56).

Results: Neither NK cell activity nor subsets showed a significant difference in relation to the cause or number of spontaneous abortions. NK cell activity in nonpregnant women who later experienced subsequent abortion with normal chromosomes (n = 10) (mean +/- SD: 42.8 +/- 15.8%) was relatively higher than that in women with subsequent live birth (control, n = 39) (32.1 +/- 13.7%) (p = 0.099). NK cell activity in women who later experienced subsequent abortion with abnormal chromosomes (n = 7) (28.7 +/- 21.4%) was the same as the level in the control.

Conclusion: Peripheral NK cell activity or subsets during nonpregnant status were not related to the cause or number of previous spontaneous abortions. A relation between preconceptional NK cell activity and later experiencing abortion with normal chromosomes should be further studied.