Cervical mucus prorperties stratifv risk for preterm birth

Abstract

Preterm birth impacts 15 million babies every year, leading to morbidity, mortality, significant health care costs, and lifelong consequences. The causes of preterm birth are unknown, resulting in ineffective treatment, but it is correlated with ascension of vaginal bacteria through the cervix, which is normally protected by a dense mucus plug during pregnancy. This mucus plug, consisting of a tight meshwork of glycoproteins called mucins, should prevent pathogens from accessing the sterile uterine environment. Cervical mucus from women at high risk and low risk for preterm birth was collected and compared. The aim of this study was to discover differences that will lead to clues about why preterm birth occurs, and ultimately what can be done about it in terms of prevention and intervention. Using rheological techniques and a translocation assay, we found that cervical mucus from women at high risk is more translucent and more elastic under both elongational and shear stress, than cervical mucus in normal pregnancies. These properties more closely resemble mucus during ovulation, when spermatozoa can most easily penetrate the barrier, than mucus in normal pregnancy. Furthermore, high risk mucus is more permeable to beads of comparable size to viruses, suggesting the barrier is weakened and foreign particles may harmfully traverse it to cause intrauterine infection. The techniques in this paper have not been previously used to study cervical mucus in the context of preterm labor, but their results may have important implications. If these mucus properties in women indeed permit increased bacterial infection through the cervix, then they can be used to stratify patients, allowing for more personalized prenatal care to lower the rate of preterm birth.