The inferior one-third portion of the uterus that projects into the vagina is the cervix.
The cervix is part of the female reproductive system and it represents the lower part of the uterus. The cervix is usually 2 to 3 cm long, cylindrical in shape, which changes during pregnancy. The central cervical canal is connecting the uterine cavity and the lumen of the vagina and it is located inside the entire cervix. The central cervical canal is essential for fertilization because sperm must travel trough it to fertilize an egg cell.