The cervix is the entrance to the uterus, or womb.

The uterus is where a woman's egg, fertilised by male sperm, grows into a baby.

The cervix leads from the uterus to the vagina (front passage, or birth canal), which connects the uterus to the outside of the body.

Normally the cervix is almost closed. There is a small space through which sperm can get in, and blood from the monthly period can get out. During labour, the cervix gradually opens up so that the baby can get out.