Infection-induced thrombin production: a potential novel mechanism for preterm premature rupture of membranes (PPROM).



Journal Title

Journal ISSN

Volume Title

Repository Usage Stats


Citation Stats


Preterm premature rupture of membranes is a leading contributor to maternal and neonatal morbidity and death. Epidemiologic and experimental studies have demonstrated that thrombin causes fetal membrane weakening and subsequently preterm premature rupture of membranes. Although blood is suspected to be the likely source of thrombin in fetal membranes and amniotic fluid of patients with preterm premature rupture of membranes, this has not been proved. Ureaplasma parvum is emerging as a pathogen involved in prematurity, which includes preterm premature rupture of membranes; however, until now, prothrombin production that has been induced directly by bacteria in fetal membranes has not been described.This study was designed to investigate whether Ureaplasma parvum exposure can induce prothrombin production in fetal membranes cells.Primary fetal membrane cells (amnion epithelial, chorion trophoblast, and decidua stromal) or full-thickness fetal membrane tissue explants from elective, term, uncomplicated cesarean deliveries were harvested. Cells or tissue explants were infected with live Ureaplasma parvum (1×105, 1×106 or 1×107 colony-forming units per milliliter) or lipopolysaccharide (Escherichia coli J5, L-5014; Sigma Chemical Company, St. Louis, MO; 100 ng/mL or 1000 ng/mL) for 24 hours. Tissue explants were fixed for immunohistochemistry staining of thrombin/prothrombin. Fetal membrane cells were fixed for confocal immunofluorescent staining of the biomarkers of fetal membrane cell types and thrombin/prothrombin. Protein and messenger RNA were harvested from the cells and tissue explants for Western blot or quantitative reverse transcription polymerase chain reaction to quantify thrombin/prothrombin protein or messenger RNA production, respectively. Data are presented as mean values ± standard errors of mean. Data were analyzed using 1-way analysis of variance with post hoc Dunnett's test.Prothrombin production and localization were confirmed by Western blot and immunostainings in all primary fetal membrane cells and tissue explants. Immunofluorescence observations revealed a perinuclear localization of prothrombin in amnion epithelial cells. Localization of prothrombin in chorion and decidua cells was perinuclear and cytoplasmic. Prothrombin messenger RNA and protein expression in fetal membranes were increased significantly by Ureaplasma parvum, but not lipopolysaccharide, treatments in a dose-dependent manner. Specifically, Ureaplasma parvum at a dose of 1×107 colony-forming units/mL significantly increased both prothrombin messenger RNA (fold changes in amnion: 4.1±1.9; chorion: 5.7±4.2; decidua: 10.0±5.4; fetal membrane: 9.2±3.0) and protein expression (fold changes in amnion: 138.0±44.0; chorion: 139.6±15.1; decidua: 56.9±29.1; fetal membrane: 133.1±40.0) compared with untreated control subjects. Ureaplasma parvum at a dose of 1×106 colony-forming units/mL significantly up-regulated prothrombin protein expression in chorion cells (fold change: 54.9±5.3) and prothrombin messenger RNA expression in decidua cells (fold change: 4.4±1.9).Our results demonstrate that prothrombin can be produced directly by fetal membrane amnion, chorion, and decidua cells. Further, prothrombin production can be stimulated by Ureaplasma parvum exposure in fetal membranes. These findings represent a potential novel underlying mechanism of Ureaplasma parvum-induced rupture of fetal membranes.





Published Version (Please cite this version)


Publication Info

Feng, Liping, Terrence K Allen, William P Marinello and Amy P Murtha (2018). Infection-induced thrombin production: a potential novel mechanism for preterm premature rupture of membranes (PPROM). American journal of obstetrics and gynecology, 219(1). pp. 101.e1–101.e12. 10.1016/j.ajog.2018.04.014 Retrieved from

This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.



Liping Feng

Associate Professor of Obstetrics and Gynecology

Liping Feng, MD's research has focused on understanding the mechanisms of pregnancy complications associated with placental development. These works are translated then to the clinical care of women through studies dedicated to identify risk factors and novel biomarkers for early prediction and prevention of adverse birth outcomes.

Dr. Feng devotes her entire career to improving pregnancy outcomes through innovative research. Dr. Feng conducts both basic science/laboratory research, as well as participates in clinical studies. Her laboratory has focused on understanding the mechanisms of placenta-originated pregnancy complications such as preeclampsia and still birth, which are important causes of perinatal and neonates’ mortality and morbidity. Currently, she has three lines of investigation focused on the roles of inflammation/infection, cell aging, and environmental exposure in placental development and subsequent pregnancy complications.

In addition, Dr. Feng has established an international collaboration in Global Women’s Health. She has affiliated with the Duke Global Health Institute (DGHI) and participates in a DGHI research. She has an interest in DGHI education, and service or policy initiatives, including mentoring and teaching graduate and professional students on fieldwork and research.


Terrence Kelburn Allen

Associate Professor of Anesthesiology


Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.