Mucus plugs in the cervix are quite different from their potentially fatal counterparts in the lungs. Cervical mucus plugs form during pregnancy from normal vaginal discharge at the base of the cervix to prevent bacteria from reaching the uterus, and thus the fetus. Although the mucus plug may come out near the end of pregnancy, this does not always make it an immediate indicator of labor. It is often confused with other aspects of pregnancy.
What exactly is a cervical mucus plug?
A cervical mucus plug is exactly what it sounds like—a thick, gelatinous blob of the mucus created by the cervix. It’s usually cream or even tan in color, but because the cervix may sometimes bleed, it may be have shades of pink or brown. This is not necessarily something to be concerned about, but sometimes it can be. It not only creates a barrier for the opening of the cervix, but will actually plug the entire cervical canal. In addition to preventing bacteria access to the uterus and fetus, the mucus plug will deliver antimicrobials, like immunoglobulin, to help keep the environment healthy and safe.
In the last stage of pregnancy, vaginal discharge often increases significantly. This is often mistaken for the mucus plug, but it is actually distinct. Because the mucus plug is sometimes expelled in bits and pieces rather than as one big glob, this is understandable. A woman’s water breaking is also completely different from losing the mucus plug.
Why does it come out?
In a perfect world, the release of the mucus plug would indicate that labor is on the way. However, every woman is different, so this is not always the case. As pregnancy progresses, the cervix begins to expand and thin, preparing for birth. This process can take some time, but mucus plug isn’t always held in for the duration. Since size, shape, and consistency all differ among women, it may come out earlier in some women, especially if it is of a thicker consistency. Mild stressors to the vagina, such as sex or an exam by a doctor, have the potential to shake it loose.
What if it comes out early?
As long as a woman is at the end of her pregnancy, there is usually nothing to worry about. In fact, some women have more than one mucus plug; if one comes out early enough, another one may form over the next few days. Some women don’t even notice when they lose their mucus plug. While others might lose it a few weeks before labor actually begins, it might not come out until the amniotic sac (or “water”) breaks, releasing a rush of fluid. However, if the mucus plug comes out earlier than 36 weeks or has an excessive amount of blood in it, experts recommend seeking medical assistance.
