Fraction of the peripheral blood concentration of CD56+/CD16-/CD3- cells in total natural killer cells as an indication of fertility and infertility

Objective: To determine whether the peripheral blood concentration of CD56(+)/CD16(-)/CD3(-) cells, the main natural killer (NK) subpopulation that colonizes the endometrium in the middle and late secretory phase, can be related to fertility or infertility status. Design: A case control study. Setting: Immunopathology department of an infertility laboratory. Patient(s): A total 99 women were selected (group 1: consecutive spontaneous aborters, n = 25; group II: sporadic spontaneous aborters, n = 30; group III: infertile, n = 33; group IV: controls, n = 11). Intervention(s): Immunophenotyping of women grouped according to their fertility status. Main Outcome Measure(s): Peripheral blood lymphocytes were examined by two- and three-color flow cytometry. Result(s): A statistically significant association between endometrial-type peripheral blood (PB) NK cell concentrations and fertility status (groups I and IV vs. groups II and III) was documented. The %(/TOTAL PB)CD56(+)CD16(-) CD3(-) NK cells was significantly higher [1] in fertile (groups I and IV) than in sporadic aborters/infertile (groups II and III) women, [2] in group I when compared with groups II and III, and [3] in group IV when compared with groups II and III. Conclusion(s): This study indicates that diminished numbers of the %(/TOTAL)CD56(+)CD16(-)CD3(-) - NK cells are related to sporadic aborters and infertile women. Thus, the fraction could be used as an indicator of subsequent successful implantation and maintenance of gestation. (C) 2003 by American Society for Reproductive Medicine.