**2. EVs in the female reproductive system**

The female reproductive system contains external and internal parts. Internal genital organs are mainly composed of the gonad (ovary), oviduct, and uterus (namely womb). As an organ whose basic functions are ovulation and the production of hormones, ovary influences a woman's feminine physical characteristics and affects the process of reproduction. In fertilization preparation, an ovulated oocyte enters the oviduct to meet spermatozoa (SPZ). Then fertilization occurs in oviduct when a sperm and an oocyte combine and fuse to form a zygote, which develops into a blastocyte and then implant uterus endometrium to further embryonic development. Finally, in the perinatal period, the fetus is delivered from the dilated cervix [5, 6]. Among these progresses, EVs coordinate the maturation of female gamete and mediate crosstalk to help successful embryo implantation (known as blastocyst implantation) and pregnancy in follicular fluid, oviduct, endometrium, vagina, semen, and embryo.
