title: Magnetic resonance signal characteristics of the cervix as pregnancy advances.
abstract: The objective of this study is to describe magnetic resonance (MR) signal intensity (SI) changes in the cervix during pregnancy. This is an observational cohort study of women with a history of preterm delivery. MR imaging sequences were performed every 3 to 4 weeks. Using 8 regions of interest, the SIs are quantified and analyzed with respect to gestational age. Twenty-seven MR studies were performed on a cohort of 8 women. The SIs of the external os are significantly greater than those of the internal os ( P = .035). Similarly, the SIs of the outer stroma are greater than those of the inner stroma (P = .002). As gestational age advances, the inner to outer stromal SI ratio increases, primarily because of a decreasing SI in the outer stromal layer (P = .03). The MR SIs of the cervical stromal zones display variability during pregnancy and decrease with advancing gestation.
authors.affiliation: Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center at Dallas, TX 75235-9032, USA. jason.pates@utsouthwestern.edu
authors.forename: Jason A
authors.initials: JA
authors.lastname: Pates
authors.forename: Nicole P
authors.initials: NP
authors.lastname: Yost
authors.forename: Qian
authors.initials: Q
authors.lastname: Oliver
authors.forename: Donald D
authors.initials: DD
authors.lastname: McIntire
authors.forename: Diane M
authors.initials: DM
authors.lastname: Twickler
mesh_terms: D000328:Adult; D002584:Cervix Uteri / Q000166:cytology* / Q000502:physiology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D011247:Pregnancy / Q000502:physiology; D011262:Pregnancy Trimester, Second / Q000502:physiology; D011263:Pregnancy Trimester, Third / Q000502:physiology; D047928:Premature Birth / Q000517:prevention & control; D011295:Prenatal Care / Q000379:methods; D017154:Stromal Cells / Q000166:cytology / Q000502:physiology; D013997:Time Factors