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The Italian guidelines on ultrasound in obstetrics and gynecology: Executive summary of recommendations for practice

Structural design in seismic areas could be based on either dissipative or non-dissipative concepts, as for example allowed in European and Italian codes. In the first case, capacity design is the basis of structural dimensioning; both strength and ductility verifications are required. In the second case, structural elements are designed to remain in the elastic field under the assigned design seismic input; ductility verifications are not enforced. In steel structures, these two design approaches might lead to very different seismic structural performances, depending on the role that the non-ductile elements and connections have in the non-dissipative design. This situation might represent a source of weakness and lead to premature failures. In the present work, with reference to a single- storey steel industrial building with moment-resisting frames in the transverse direction and con- centric braces in the longitudinal direction, the critical issues encountered when modelling the post- elastic behaviour of a non-dissipative steel structure are discussed. Subsequently, a comparison is made with a structure with the same geometry, designed with dissipative structural behaviour.

OBJECTIVES: Monoamniotic twin pregnancies are at increased risk of perinatal complications, primarily owing to the risk of cord entanglement. There is no recommendation on whether such pregnancies should be managed in hospital or can be safely managed in an outpatient setting, and the timing of planned delivery is also a subject of debate. The aim of this study was to compare the perinatal outcomes of inpatient vs outpatient fetal surveillance approaches employed among 22 participating study centers, and to calculate the fetal and neonatal death rates according to gestational age, in non-anomalous monoamniotic twins from 26 weeks' gestation. METHODS: The MONOMONO study was a multinational cohort study of consecutive women with monochorionic monoamniotic twin pregnancies, who were referred to 22 university hospitals in Italy, the USA, the UK and Spain, from January 2010 to January 2017. Only non-anomalous uncomplicated monoamniotic twin pregnancies with two live fetuses at 26 + 0 weeks' gestation were included in the study. In 10 of the centers, monoamniotic twins were managed routinely as inpatients, whereas in the other 12 centers they were managed routinely as outpatients. The primary outcome was intrauterine fetal death. We also planned to assess fetal and neonatal death rates according to gestational age per 1-week interval. Outcomes are presented as odds ratio (OR) with 95% CIs. The main outcome was analyzed using both standard logistic regression analysis, in which each fetus was treated as an independent unit, and a generalized mixed-model approach, with each twin pair treated as a cluster unit, considering that the outcome for a twin is not independent of that of its cotwin. RESULTS: 195 consecutive pregnant women with a non-anomalous uncomplicated monoamniotic twin gestation (390 fetuses) were included. Of these, 75 (38.5%) were managed as inpatients and 120 (61.5%) as outpatients. The overall perinatal loss rate was 10.8% (42/390) with a peak fetal death rate of 4.3% (15/348) occurring at 29 weeks' gestation. There was no significant difference in mean gestational age at delivery (31 weeks), birth weight (∼1.6 kg), or emergency delivery rate between the inpatient and outpatient surveillance groups. Based on generalized mixed-model analysis, there was no statistically significant difference in fetal death rates between inpatient management commencing from around 26 weeks compared with outpatient surveillance protocols from 30 weeks (3.3% vs 10.8%; adjusted OR 0.21 (95% CI, 0.04-1.17)). Maternal length of stay in the hospital was 42.1 days in the inpatient group, and 7.4 days in the outpatient group (mean difference 34.70 days (95% CI, 31.36-38.04 days). From 32 + 0 to 36 + 6 weeks, no fetal or neonatal death in either group was recorded. 46 fetuses were delivered after 34 + 0 weeks, and none of them died in utero or within the first 28 days postpartum. CONCLUSION: In uncomplicated monoamniotic twins, inpatient surveillance is associated with similar fetal mortality as outpatient management. After 31 + 6 weeks, and up to 36 + 6 weeks, there were no intrauterine fetal deaths or neonatal deaths. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Objective To assess the performance of fetal magnetic resonance imaging (MRI) in detecting associated anomalies in fetuses diagnosed with isolated corpus callosal (CC) anomaly on multiplanar ultrasound evaluation of the fetal brain (neurosonography). Methods This was a multicenter, retrospective cohort study involving 14 fetal medicine centers in Italy, UK, Portugal, Canada, Austria and Spain. Inclusion criteria were fetuses with an apparently isolated CC anomaly, defined as an anomaly of the CC and no other additional central nervous system (CNS) or extra-CNS abnormality detected on expert ultrasound, including multiplanar neurosonography; normal karyotype; maternal age >= 18 years; and gestational age at diagnosis >= 18 weeks. The primary outcome was the rate of additional CNS abnormalities detected exclusively on fetal MRI within 2 weeks following neurosonography. The secondary outcomes were the rate of additional abnormalities according to the type of CC abnormality (complete (cACC) or partial (pACC) agenesis of the CC) and the rate of additional anomalies detected only on postnatal imaging or at postmortem examination. Results A total of 269 fetuses with a sonographic prenatal diagnosis of apparently isolated CC anomalies (207 with cACC and 62 with pACC) were included in the analysis. Additional structural anomalies of the CNS were detected exclusively on prenatal MRI in 11.2% (30/269) of cases, with malformations of cortical development representing the most common type of anomaly. When stratifying the analysis according to the type of CC anomaly, the rate of associated anomalies detected exclusively on MRI was 11.6% (24/207) in cACC cases and 9.7% (6/62) in pACC cases. On multivariate logistic regression analysis, only maternal body mass index was associated independently with the likelihood of detecting associated anomalies on MRI (odds ratio, 1.07 (95% CI, 1.01-1.14); P = 0.03). Associated anomalies were detected exclusively after delivery and were missed on both types of prenatal imaging in 3.9% (8/205) of fetuses with prenatal diagnosis of isolated anomaly of the CC. Conclusion In fetuses with isolated anomaly of the CC diagnosed on antenatal neurosonography, MRI can identify a small proportion of additional anomalies, mainly malformations of cortical development, which are not detected on ultrasound. (c) 2021 International Society of Ultrasound in Obstetrics and Gynecology.

The identification of intrapartum hypoxia is among the current challenges of the Obstetric practice. Available data have shown that such hypoxic events, despite being rare, most commonly occur in uneventful and apparently low risk pregnancies in appropriately grown fetuses. The antenatal monitoring of fetal wellbeing aims to identify those fetuses at risk of hypoxic events related to labour and delivery and promptly arrange effective interventions in order to prevent adverse perinatal outcomes. Nevertheless, continuous intrapartum monitoring by means of cardiotocography (CTG) has not demonstrated a significant reduction in the incidence of adverse perinatal outcome and has been associated with an increase in the caesarean section rate, particularly among women considered at low risk. Available evidences from the literature suggest that abnormalities in the uterine artery Doppler and in the ratio between fetal cerebral and umbilical Doppler (i.e. cerebroplacental ratio, CPR) are associated with conditions of subclinical placental function occurring in fetuses who have failed to achieve their growth potential, hence at risk of intrapartum complications. The purpose of this study is to prospectively assess maternal and fetal Doppler in early labour in order to evaluate whether abnormalities of the Doppler parameters may identify those fetuses at higher risk of intrapartum distress. L’identificazione delle complicanze ipossiche intrapartum rappresenta una delle sfide della pratica ostetrica moderna. I dati a nostra disposizione dimostrano che tali eventi, seppur rari, hanno incidenza maggiore in gravidanze non complicate e quindi “a basso rischio” sulla base dei criteri clinico-anamnestici che attualmente vengono utilizzati per la definizione del rischio ostetrico. Il monitoraggio prenatale del benessere fetale mira ad identificare quel ristretto gruppo di feti a rischio di complicanze asfittiche correlate con il travaglio ed il parto ed instaurare tempestivamente interventi efficaci per prevenire esiti perinatali sfavorevoli. In tale contesto, l’impiego su ampia scala del monitoraggio intrapartum in continuo mediante cardiotocografia non ha dimostrato una riduzione significativa di eventi avversi perinatali ma ha comportato un significativo aumento del tasso di tagli cesarei, in particolare in pazienti prive di fattori di rischio ostetrico. Recenti evidenze della letteratura hanno dimostrato che, in gravidanze a basso rischio anamnestico e al di fuori del travaglio, la valutazione della velocimetria Doppler delle arterie uterine materne e del rapporto tra la velocimetria Doppler cerebrale e ombelicale (rapporto cerebroplacentare o CPR) nel feto è in grado di identificare condizioni di riduzione della riserva funzionale placentare e conseguente adattamento fetale ad una ipossia placentare cronica, che sono potenzialmente associate con un aumento del rischio di distress intrapartum e di outcomes perinatali avversi anche in gestanti considerate prive di fattori di rischio ostetrico. Il fine ultimo di tale progetto di Dottorato è la valutazione prospettica del triage mediante parametri Doppler velocimetrici materni e fetali misurati all’inizio del travaglio in una coorte di gestanti a basso rischio anamnestico, nell’identificazione dei casi a maggior rischio di distress intrapartum.

This paper proposes a model for analysing the non-linear behaviour of steel concrete composite beams prestressed by external slipping cables, taking into account the deformability of the interface shear connection. By assuming a suitable admissible displacement field for the composite beam, the balance condition is obtained by the virtual work principle. The solution is numerically achieved by approximating the unknown displacement functions as series of shape functions according to the Ritz method. The model is applied to real cases by showing the consequences of different connection levels between the concrete slab and the steel beam. Particular attention is focused on the limited ductility of the shear connection that may be the cause of premature failure of the composite girder.

This article describes the structural design, nonlinear modeling, and seismic analysis of prototype single-storey non-residential steel buildings made of moment-resisting portal frames in the transverse direction and concentric braces in the longitudinal direction. Various design parameters (building geometry, seismic hazard, foundation soil category) and different modeling assumptions (bare frame model, model including cladding elements, ground motions including vertical accelerations, and modeling uncertainties) were considered to investigate their effects on the simulated seismic performance.

Objective: The aim of this study was to report the rate of additional anomalies detected exclusively at prenatal magnetic resonance imaging (MRI) in fetuses with isolated severe ventriculomegaly undergoing neurosonography. Method: Multicenter, retrospective, cohort study involving 20 referral fetal medicine centers in Italy, United Kingdom, Spain and Denmark. Inclusion criteria were fetuses affected by isolated severe ventriculomegaly (≥15 mm), defined as ventriculomegaly with normal karyotype and no other additional central nervous system (CNS) and extra-CNS anomalies on ultrasound. In all cases, a multiplanar assessment of fetal brain as suggested by ISUOG guidelines on fetal neurosonography had been performed. The primary outcome was the rate of additional CNS anomalies detected exclusively at fetal MRI within two weeks from neurosonography. Subgroup analyses according to gestational age at MRI (

Objective: The objective of this study was to longitudinally evaluate maternal echocardiographic findings in uncomplicated twin gestations according to chorionicity. Methods: Healthy women with twin pregnancy were assessed with transthoracic echocardiography across the first, second, and third trimesters. Cardiac findings were compared within each group and between monochorionic (MC) and dicho­rionic (DC) pregnancies. Results: Overall, 19 MC and 48 DC uncomplicated twin pregnancies were included. In the MC group, no significant maternal haemodynamic changes were documented across gestation, with the exception of a decrease in ejection fraction. Compared to DC pregnancies, in the MC set lower cardiac output (second and third trimester, p = 0.001 and p = 0.006, respectively) and higher total vascular resistance (first trimester, p = 0.032) were observed. Regarding the diastolic function in MC twins, significantly higher values were observed for mitral E/A ratio (third trimester, p = 0.014), septal mitral E1/A1 ratio (third trimester, p = 0.030), lateral mitral E1 (second and third trimester, p = 0.014 and p = 0.029, respectively), and E1/A1 ratio (third trimester, p = 0.006). Conclusions: Maternal cardiac adaptation in twin pregnancy seems to differ significantly according to chorionicity. In particular, in MC pregnancies the impairment of diastolic function is less pronounced, presumably due to the lower circulating volume.