High NK cell activity in early pregnancy correlates with subsequent abortion with normal chromosomes in women with recurrent abortion.

PROBLEM: The aim of this study was to assess the role of natural killer (NK) cells in pregnant women with a history of recurrent spontaneous abortion (RSA).

METHOD OF STUDY: Consecutive 66 pregnant women with a history of RSA were prospectively assessed for peripheral NK cell activity, percentage of the NK cell subsets, and subsequent pregnancy outcome.

RESULTS

NK cell activity in women with subsequent live birth (group I) at 4-5 gestational weeks (GW) (mean +/- SD, 32.5 +/- 12.31%) significantly decreased at 6-7 GW (28.1 +/- 12.1%) and at 8 9 GW (28.0 +/- 11.8%). NK cell activity in women with subsequent abortion with normal chromosomes (group II) at 6 7 GW (41.2 +/- 19.0%) was significantly higher than that in group I women, while NK cell activity at 6-7 GW in women with subsequent abortion with abnormal chromosomes (group III) was the same as the level in group I women.

CONCLUSIONS

High NK cell activity at 6-7 GW correlates with subsequent abortion with normal chromosomes.