Cytokines in the culture medium of pre-implantation blastocysts could serve as predictive biomarkers for embryo implantation potential in frozen embryo transfer cycles.

Summary: When families use IVF to have a baby, doctors want to pick the best embryo to transfer to the mother. Usually, they just look at how the embryo looks under a microscope. But now, scientists have found a new way to help. By testing the liquid the embryo grows in for tiny signals called "cytokines," doctors might be able to predict which embryo is most likely to lead to a successful pregnancy. This new test is safe for the embryo and could make IVF more successful in the future.