“…Among various embryokines, granulocyte-macrophage colony-stimulating factor (GM-CSF) has attracted much attention. GM-CSF is expressed in female genital tract, and as a developmental programming agent, it enhances cell proliferation, embryo progression, blastocyst hatching, and embryo implantation [1,3,[16][17][18][19][20][21][22][23]. Especially, some existing data have indicated a link between decreased GM-CSF levels and reproductive pathologies in women, including miscarriage, intrauterine fetal growth retardation, preeclampsia, and preterm delivery Capsule Although no benefit of GM-CSF on embryo quality was observed, the addition of this factor significantly decreased the occurrence of chemical pregnancy of women aged over 35 years, indicating the role of GM-CSF in improving implantation competence of embryos derived from elderly infertile women.…”