Definitions for "Mucus plug"
A small plug of mucous that seals the cervical opening during pregnancy. Loss of this plug appears as a thick, brownish-pink vaginal discharge. You may or may not be aware of the loss of this plug.
Cervical secretion of mucus used to seal the uterus throughout pregnancy. It is usually released just prior to labor.
A small plug of mucus that seals the cervix to protect your baby from infection.