Figure 1.

Schematic representation of the sperm travel through the female reproductive tract. Sperm enter in contact with the different extracellular vesicles produced in the vagina, the uterus and the oviduct. Once fertilization takes place, the embryo will come into contact with the EVs produced by the oviduct and the uterus where the embryo and the future fetus will remain for the rest of the pregnancy until delivery. Note that the embryo also produces EVs that allow bidirectional communication with the mother tissue (oviduct).