Utero-cervical angle to predict the risk of spontaneous preterm birth: a review of literature.

BACKGROUND: The aim of this paper was to evaluate the predictive role of the uterocervical angle (UCA) in spontaneous preterm birth (sPTB). METHODS: A systematic review of the literature was performed including all studies reporting the association between UCA and sPTB. Searches were performed with the use of a combination of keywords: "cervical length," "uterocervical angle," and "preterm birth" from inception of each database to March 2022. The statistical evaluations were carried out using the Comprehensive Meta-Analysis version 3 (Biostat Inc. USA). RESULTS: Sixteen studies all conducted on the second trimester UCA as well as its association with sPTB were included in this study. In all studies the measurements of cervical length (CL) and UCA were performer in the second trimester, except in one that in the third trimester. In most studies the CL is greater than 30 mm and the UCA is greater than 110 °. In seven studies women with symptoms were considered while in 8 studies the women were asymptomatic. CONCLUSIONS: It is too early for it to reach a firm conclusion on UCA utilization in clinical settings. A higher UCA measurement (greater than 150°) is an important risk factor for deliveries before 37 weeks' gestation. It provides a higher diagnostic performance in high risk patients than the CL measurement. However, the most relevant ultrasound parameter for the prediction of delivery within the next few data in women with preterm delivery remains the cervical length. There is a need to consider both markers and create protocols so that the values obtained with UCA and those with CL can make a real contribution to decisions to be made rather than using only CL.

Fetal Cerebellar Area: Ultrasound Reference Ranges at 13-39 Weeks of Gestation.

BACKGROUND AND OBJECTIVES: The present study aims to provide prenatal 2-dimensional ultrasonographic (2D-US) nomograms of the normal cerebellar area. MATERIALS AND METHODS: This is a prospective cross-sectional analysis of 252 normal singleton pregnancies, ranging from 13 to 39 weeks of gestation. The operator performed measurements of the fetal cerebellar area in the transverse plane using 2D-US. The relationship between cerebellar area and gestational age (GA) was determined through regression equations. RESULTS: A significant, strong positive correlation was investigated between the cerebellar area with GA (r-value = 0.89), and a positive correlation indicates that with increasing GA, the cerebellar area increased in all the participants of the study. Several 2D-US nomograms of the normal cerebellar area were provided, and an increase of 0.4% in the cerebellar area each week of GA was reported. CONCLUSIONS: We presented information on the typical dimensions of the fetal cerebellar area throughout gestation. In future studies, it could be evaluated how the cerebellar area changes with cerebellar abnormalities. It should be established if calculating the cerebellar area in addition to the routine transverse cerebellar diameter may help in discriminating posterior fossa anomalies or even help to identify anomalies that would otherwise remain undetected.