Critical Period: Embryology As is well known, a certain organ arises much earlier or later in the embryo than certain others.
How soon after my mucus plug passes will labor begin? Passing a mucus plug is a sign that your cervix is dilating and that your body is preparing for birth. Labor could be hours, days, or even weeks away as the cervix gradually opens. The mucus plug is usually clear, slightly pink or blood tinged in color. It can be stringy mucus or a sticky discharge.
Some breeders report their dogs' mucus plug being expelled up to a week before labor starts, with an average of about four to five days, but then others report birth taking place within a few hours after they notice a mucus plug released all at once in a big clump or the presence of a blood show..