title: Increased Levels of Cell-Free miR-517a and Decreased Levels of Cell-Free miR-518b in Maternal Plasma Samples From Placenta Previa Pregnancies at 32 Weeks of Gestation.
abstract: OBJECTIVE
  The aim of this study was to clarify the association between placenta previa and circulating levels of cell-free pregnancy-associated placenta-specific microRNAs (miRNAs) in maternal plasma.
  
  
  METHODS
  Twenty singleton pregnancies with placenta previa (placenta previa group) and 26 uncomplicated pregnancies (control group) were recruited. Blood sampling was performed at 32 weeks of gestation, and cesarean delivery in all cases of placenta previa was performed at a mean gestational age of 37 weeks. The maternal plasma concentrations of cell-free pregnancy-associated placenta-specific miRNAs (miR-517a and miR-518b) were measured by absolute quantitative real-time reverse transcription-polymerase chain reaction.
  
  
  RESULTS
  Plasma concentrations of cell-free miR-517a were significantly higher in the placenta previa group than that in the control group (P = .011), while the plasma concentration of cell-free miR-518b was significantly lower in the placenta previa group than that in the control group (P = .004). Plasma concentrations of cell-free miR-517a in placenta previa were significantly higher in placenta previa with alert bleeding later group than those in placenta previa without alert bleeding group or control group (P = .030 or .047, respectively) and correlated with the volume of hemorrhage at delivery (R and P value: .512 and .025).
  
  
  CONCLUSIONS
  Plasma concentrations of cell-free miR-517a and miR-518b at 32 weeks of gestation were altered in pregnant women with placenta previa, and the circulating level of cell-free miR-517a in placenta previa may be a predictive marker for the risks of alert bleeding later and massive hemorrhage at delivery.
authors.affiliation: Department of Obstetrics and Gynecology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Hasegawa
authors.affiliation: Department of Obstetrics and Gynecology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan kiyonori@nagasaki-u.ac.jp.
authors.forename: Kiyonori
authors.initials: K
authors.lastname: Miura
authors.affiliation: Department of Obstetrics and Gynecology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Ai
authors.initials: A
authors.lastname: Higashijima
authors.affiliation: Department of Obstetrics and Gynecology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Shuhei
authors.initials: S
authors.lastname: Abe
authors.affiliation: Department of Obstetrics and Gynecology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Shoko
authors.initials: S
authors.lastname: Miura
authors.affiliation: Department of Human Genetics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Koh-ichiro
authors.initials: K
authors.lastname: Yoshiura
authors.affiliation: Department of Obstetrics and Gynecology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Masuzaki
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D002585:Cesarean Section / Q000009:adverse effects; D015536:Down-Regulation; D005260:Female; D005865:Gestational Age; D006801:Humans; D035683:MicroRNAs / Q000097:blood* / Q000235:genetics; D010865:Pilot Projects; D010923:Placenta Previa / Q000097:blood* / Q000175:diagnosis / Q000235:genetics / Q000601:surgery; D006473:Postpartum Hemorrhage / Q000209:etiology; D011247:Pregnancy; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; C546349:MIRN517 microRNA, human; C571457:MIRN518 microRNA, human; D035683:MicroRNAs
keywords: alert bleeding; hemorrhage; maternal plasma; placenta previa; pregnancy-associated microRNA