What is the cervix?

The cervix is lowermost part of the uterus, which protrudes like a bottleneck into the upper vagina. The mouth of the cervix is sealed by a mucus plug, which acts as a barrier between the baby and the world. The role of the cervix is vital during pregnancy since it keeps the baby in place during pregnancy and then opens (dilates) during labour to allow the baby to be born.

See also:
Cervix – Incompetent
Cervix – Ripe