Longitudinal evaluation of cervical length and shear wave elastography in women with spontaneous preterm birth

To compare the temporal changes in cervical length (CL) and cervical shear wave elastography (CSWE) across gestation between spontaneous preterm birth (sPTB) and term birth (TB) groups. This was a prospective longitudinal study of 1264 unselected singleton (n = 1143) and twin (n = 121) pregnancies. CSWE for 6 regions of interest (inner, middle, and external parts of anterior and posterior lips) and CL were measured by transvaginal ultrasonography at 11-16, 17-21, 22-25, and 28-33 weeks of gestation. Multilevel mixed-effects analysis was performed to compare CL and CSWE longitudinally between sPTB and TB groups. There were 90 (7.1%) cases of sPTB with delivery <37 weeks. sPTB group had shorter CL across gestation when controlling for maternal weight, conception method, history of cervical surgery and clinical visits (p < 0.001). While there was no difference in CL between the two study groups during the first two visits, a more dramatic decrease in CL was observed in the sPTB group in the later visits (p < 0.05). There was a gradual decrease in CSWE in both study groups during pregnancy. However, sPTB had significantly lower CSWE across gestation, when adjusted for maternal age, weight, height, body mass index, and clinical visits (p = 0.048). Twin pregnancy had no effect on CL and CSWE across gestation (p > 0.05). sPTB group have lower CSWE and CL measurements across gestation, compared with TB group. Evaluation of CL and CSWE trends may be a useful tool for predicting the risk of sPTB. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.