The female reproductive system (or female genital system) contains two main parts: the uterus, which hosts the developing fetus, produces vaginal and uterine secretions, and can pass sperm through to the Fallopian tubes; and the ovaries, which produce the female's egg cells. These parts are internal; the vagina meets the external organs at the vulva, which includes the labia, clitoris and urinary meatus. The vagina is attached to the uterus through the cervix, while the uterus is attached to the ovaries via the Fallopian tubes. At certain intervals, the ovaries release an ovum, which passes through the Fallopian tube into the uterus. If, in this transit, it meets with sperm, a single sperm can enter and merge with the egg, fertilizing it. Corresponding equivalent among males is the male reproductive system.