Cervical mucus plug

A cervical mucus plug (operculum) is a plug that fills and seals the cervical canal during pregnancy. It is formed by a small amount of cervical mucus that condenses to form a cervical mucus plug during pregnancy.[1]

The cervical mucus plug (CMP) acts as a protective barrier by deterring the passage of bacteria into the uterus, and contains a variety of antimicrobial agents, including immunoglobulins, and similar antimicrobial peptides to those found in nasal mucus.The CMP inhibits the migration of vaginal bacteria towards the uterus, protecting against opportunistic infections that can lead to pelvic inflammatory disease and the onset of preterm labor. Ensuring the presence and proper function of the CMP is essential in reducing severe infections and promoting overall reproductive health.[1]

During pregnancy, the mucus has viscoelastic properties and can be described as cloudy, clear, thick, salty and sticky. It holds innate and adaptive immunity properties allowing for protection of the cervical epithelium during pregnancy. Toward the end of the pregnancy, when the cervix thins, some blood is released into the cervix which causes the mucus to become bloody. As the pregnancy progresses into labor, the cervix begins to dilate and the mucus plug is discharged. The plug may come out as a plug, a lump, or simply as increased vaginal discharge over several days. Loss of the mucus plug does not necessarily mean that delivery or labor is imminent.[2]

Having intercourse or a vaginal examination can also disturb the mucus plug and cause a pregnant individuals to see some blood-tinged discharge, even when labor does not begin over the next few days.[1]

A cervical mucus plug can allow for identification of an individual's ovulation cycle and serve as fertility indicator. The cervical mucus plug proteome changes throughout an individual's menstrual cycle and allows for identification of specific proteins that may represent different stages of ovulation.[3]

Some proteins found within the cervical mucus of patients with endometriosis could serve as potential biomarkers for the disease.[3]

  1. ^ a b c Cite error: The named reference :1 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference :2 was invoked but never defined (see the help page).
  3. ^ a b Fernandez-Hermida Y, Grande G, Menarguez M, Astorri AL, Azagra R (2018). "Proteomic Markers in Cervical Mucus". Protein and Peptide Letters. 25 (5): 463–471. doi:10.2174/0929866525666180418122705. PMID 29667544. S2CID 4956453.