Conclusion
The results indicated that the reference range for uNK cell density derived from natural cycles may apply to HRT cycles.
Results
There was no significant difference (P > 0.05) in uNK cell density between natural cycles (median 2.28%, range 0.99%-4.78%) and HRT cycles (median 2.55%, range 0.69%-5.02%) in women undergoing IVF-ET treatment on the putative day of blastocyst transfer. Using reference range from 1.2% to 4.5% for uNK cell density, there was no significant difference (P > 0.05) in high uNK cell density proportion between natural cycles (8%, 6/75) and HRT cycles (10.2%, 11/108).