It should be a cervical mucus plug, which is a viscous colorless or yellow transparent viscous liquid secreted on the cervix. This is a special protective substance produced by people during pregnancy. When a woman is pregnant, the cervix will become soft and long, and mucus plugs will be secreted to block the cervix, that is, the cervix. Otherwise, bacteria will enter the uterus and affect the normal development of the fetus. The cervical plug will still be secreted, and then it will be gradually diluted, so it can flow out.