Introduction: Preterm birth is the leading cause of neonatal morbidity and mortality not attributable to congenital anomalies or aneuploidy. It has been shown that a shortened cervix is a powerful indicator of preterm births in women with singleton and twin gestations – the shorter the cervical length, the higher the risk of spontaneous preterm birth. Ultrasound measurements of the cervix are a more accurate way of determining cervical length (CL) than using a digital method. Background: There are three approaches that may be used to perform ultrasound measurements of the cervix; these are the transabdominal (TA), transperineal (TP) and the transvaginal (TV) approach. The TV approach is considered to be the gold standard. In women who are considered to be at a high risk of preterm birth it is now recommended that the cervix is measured at the mid‐trimester ultrasound using the TV ultrasound approach. For women considered to be at a historical low risk the TV scan is not recommended, however it has been found that many women who deliver a preterm baby have no known risk factors. Conclusion: There is contradictory evidence in the literature with regard to the correlation between TA, TP and TV measurements. This article provides an overview of these three approaches with a focus on the clinical value for the assessment of the maternal cervix.

Chronic liver diseases are a substantial worldwide problem that are increasing in prevalence.

Ultrasound-induced artifacts appear to affect the transmission of the elastographic main pulse, with cervical position contributing to suboptimal shear wave production in the posterior cervix. Reliable shear wave propagation can be achieved in the anterior cervix in most patients.

1Objectives This research aimed to identify biological and technical confounders in the non-2 pregnant cervix when applying shear wave elastography with an endovaginal transducer.3 Methods Cervical speed measurements were obtained at the internal and external os, anterior 4 and posterior portions of the cervix using a transvaginal approach in 69 non-gravid patients. 5Results Reliable measurements were obtained at the external os and internal os, anteriorly 6 and posteriorly, in 63, 55, 55 and 26 patients respectively. The mean speed obtained at the 7 external os, anteriorly and posteriorly, was 2.52 ± 0.49m/s and 2.87 ± 0.63m/s respectively, 8 and at the internal os anteriorly and posteriorly, 3.29 ± 0.79m/s and 4.10 ± 1.11m/s 9 respectively. The difference in speed between all regions was statistically significant 10 (p<0.05). 11 Conclusion Ultrasound -induced artifacts appear to affect the transmission of the 12 elastographic main pulse, with cervical position contributing to suboptimal shear wave 13 production in the posterior cervix. Reliable shear wave propagation can be achieved in the 14 anterior cervix in most patients. 15 16Retention of a pregnancy requires the cervix to maintain strength to withstand multiple forces 22 from the uterus, from the weight of the growing fetus and amniotic sac, and also passive 23 pressure from the uterine wall. The cervix softens and shortens throughout pregnancy and 24 finally dilates for the fetus to be delivered vaginally. Premature softening of the cervix is 25 associated with early shortening of cervical length and subsequent spontaneous preterm birth 26 (SPTB). 1 The cervix can be described as soft, firm or medium based on a digital 27 examination, but this method is subjective to the clinician, and creates difficulties due to the 28 expectation that the cervix will soften initially at the proximal portion. 1 29Currently, the length of the cervix assessed with transvaginal ultrasound (TVU) is the feature 30 that is assessed to indicate cervical strength and premature softening. 2 A short cervix has 31 been shown to be a significant risk factor for subsequent SPTB. 3 In women with a high risk 32 of SPTB due to medical history, a shortened cervical length on TVU has a sensitivity of over 33 50% for subsequent SPTB. However, in low risk women the sensitivity is reduced to 37%, 4,5 34 and the appropriate method for screening for SPTB in these women is yet to be established. 35With preterm birth affecting 13 million babies every year and the implications for neonatal 36 mortality and morbity, 6 there is a need for a non-invasive technique to assess cervical 37 strength with greater sensitivity than length alone. 38Ultrasound elastography assesses mechanical properties of tissues in the region being 39 examined. The basis for this technique is that soft tissue deforms differently from firm tissue 40 and the elastographic images reflect this difference. 7 Utilizing strain elastography, it has 41 been proposed it may be possible to identify women in the historically low r...

Introduction: Transient elastography is commonly utilised in liver clinics as a non-