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Objective: To compare the predictive performance of three different mathematical models for first‐trimester screening of pre‐eclampsia (PE), which combine maternal risk factors with mean arterial pressure (MAP), uterine artery pulsatility index (UtA‐PI) and serum placental growth factor (PlGF), and two risk‐scoring systems. Methods: This was a prospective cohort study performed in eight fetal medicine units in five different regions of Spain between September 2017 and December 2019. All pregnant women with singleton pregnancy and a non‐malformed live fetus attending their routine ultrasound examination at 11 + 0 to 13 + 6 weeks' gestation were invited to participate in the study. Maternal characteristics and medical history were recorded and measurements of MAP, UtA‐PI, serum PlGF and pregnancy‐associated plasma protein‐A (PAPP‐A) were converted into multiples of the median (MoM). Risks for term PE, preterm PE (< 37 weeks' gestation) and early PE (< 34 weeks' gestation) were calculated according to the FMF competing‐risks model, the Crovetto et al. logistic regression model and the Serra et al. Gaussian model. PE classification was also performed based on the recommendations of the National Institute for Health and Care Excellence (NICE) and the American College of Obstetricians and Gynecologists (ACOG). We estimated detection rates (DR) with their 95% CIs at a fixed 10% screen‐positive rate (SPR), as well as the area under the receiver‐operating‐characteristics curve (AUC) for preterm PE, early PE and all PE for the three mathematical models. For the scoring systems, we calculated DR and SPR. Risk calibration was also assessed. Results: The study population comprised 10 110 singleton pregnancies, including 32 (0.3%) that developed early PE, 72 (0.7%) that developed preterm PE and 230 (2.3%) with any PE. At a fixed 10% SPR, the FMF, Crovetto et al. and Serra et al. models detected 82.7% (95% CI, 69.6–95.8%), 73.8% (95% CI, 58.7–88.9%) and 79.8% (95% CI, 66.1–93.5%) of early PE; 72.7% (95% CI, 62.9–82.6%), 69.2% (95% CI, 58.8–79.6%) and 74.1% (95% CI, 64.2–83.9%) of preterm PE; and 55.1% (95% CI, 48.8–61.4%), 47.1% (95% CI, 40.6–53.5%) and 53.9% (95% CI, 47.4–60.4%) of all PE, respectively. The best correlation between predicted and observed cases was achieved by the FMF model, with an AUC of 0.911 (95% CI, 0.879–0.943), a slope of 0.983 (95% CI, 0.846–1.120) and an intercept of 0.154 (95% CI, –0.091 to 0.397). The NICE criteria identified 46.7% (95% CI, 35.3–58.0%) of preterm PE at 11% SPR and ACOG criteria identified 65.9% (95% CI, 55.4–76.4%) of preterm PE at 33.8% SPR. Conclusions: The best performance of screening for preterm PE is achieved by mathematical models that combine maternal factors with MAP, UtA‐PI and PlGF, as compared to risk‐scoring systems such as those of NICE and ACOG. While all three algorithms show similar results in terms of overall prediction, the FMF model showed the best performance at an individual level. © 2024 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Objective: Effective first‐trimester screening for pre‐eclampsia (PE) can be achieved using a competing‐risks model that combines risk factors from the maternal history with multiples of the median (MoM) values of biomarkers. A new model using artificial intelligence through machine‐learning methods has been shown to achieve similar screening performance without the need for conversion of raw data of biomarkers into MoM. This study aimed to investigate whether this model can be used across populations without specific adaptations. Methods: Previously, a machine‐learning model derived with the use of a fully connected neural network for first‐trimester prediction of early (< 34 weeks), preterm (< 37 weeks) and all PE was developed and tested in a cohort of pregnant women in the UK. The model was based on maternal risk factors and mean arterial blood pressure (MAP), uterine artery pulsatility index (UtA‐PI), placental growth factor (PlGF) and pregnancy‐associated plasma protein‐A (PAPP‐A). In this study, the model was applied to a dataset of 10 110 singleton pregnancies examined in Spain who participated in the first‐trimester PE validation (PREVAL) study, in which first‐trimester screening for PE was carried out using the Fetal Medicine Foundation (FMF) competing‐risks model. The performance of screening was assessed by examining the area under the receiver‐operating‐characteristics curve (AUC) and detection rate (DR) at a 10% screen‐positive rate (SPR). These indices were compared with those derived from the application of the FMF competing‐risks model. The performance of screening was poor if no adjustment was made for the analyzer used to measure PlGF, which was different in the UK and Spain. Therefore, adjustment for the analyzer used was performed using simple linear regression. Results: The DRs at 10% SPR for early, preterm and all PE with the machine‐learning model were 84.4% (95% CI, 67.2–94.7%), 77.8% (95% CI, 66.4–86.7%) and 55.7% (95% CI, 49.0–62.2%), respectively, with the corresponding AUCs of 0.920 (95% CI, 0.864–0.975), 0.913 (95% CI, 0.882–0.944) and 0.846 (95% CI, 0.820–0.872). This performance was achieved with the use of three of the biomarkers (MAP, UtA‐PI and PlGF); inclusion of PAPP‐A did not provide significant improvement in DR. The machine‐learning model had similar performance to that achieved by the FMF competing‐risks model (DR at 10% SPR, 82.7% (95% CI, 69.6–95.8%) for early PE, 72.7% (95% CI, 62.9–82.6%) for preterm PE and 55.1% (95% CI, 48.8–61.4%) for all PE) without requiring specific adaptations to the population. Conclusions: A machine‐learning model for first‐trimester prediction of PE based on a neural network provides effective screening for PE that can be applied in different populations. However, before doing so, it is essential to make adjustments for the analyzer used for biochemical testing. © 2023 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the diagnostic accuracy of the Fetal Medicine Foundation (FMF) competing‐risks model, incorporating maternal characteristics, mean arterial pressure (MAP), uterine artery pulsatility index (UtA‐PI) and placental growth factor (PlGF) (the 'triple test'), for the prediction at 11–13 weeks' gestation of preterm pre‐eclampsia (PE) in a Spanish population. Methods: This was a prospective cohort study performed in eight fetal medicine units in five different regions of Spain between September 2017 and December 2019. All pregnant women with a singleton pregnancy and a non‐malformed live fetus attending a routine ultrasound examination at 11 + 0 to 13 + 6 weeks' gestation were invited to participate. Maternal demographic characteristics and medical history were recorded and MAP, UtA‐PI, serum PlGF and pregnancy‐associated plasma protein‐A (PAPP‐A) were measured following standardized protocols. Treatment with aspirin during pregnancy was also recorded. Raw values of biomarkers were converted into multiples of the median (MoM), and audits were performed periodically to provide regular feedback to operators and laboratories. Patient‐specific risks for term and preterm PE were calculated according to the FMF competing‐risks model, blinded to pregnancy outcome. The performance of screening for PE, taking into account aspirin use, was assessed by calculating the area under the receiver‐operating‐characteristics curve (AUC) and detection rate (DR) at a 10% fixed screen‐positive rate (SPR). Risk calibration of the model was assessed. Results: The study population comprised 10 110 singleton pregnancies, including 72 (0.7%) that developed preterm PE. In the preterm PE group, compared to those without PE, median MAP MoM and UtA‐PI MoM were significantly higher, and median serum PlGF MoM and PAPP‐A MoM were significantly lower. In women with PE, the deviation from normal in all biomarkers was inversely related to gestational age at delivery. Screening for preterm PE by a combination of maternal characteristics and medical history with MAP, UtA‐PI and PlGF had a DR, at 10% SPR, of 72.7% (95% CI, 62.9–82.6%). An alternative strategy of replacing PlGF with PAPP‐A in the triple test was associated with poorer screening performance for preterm PE, giving a DR of 66.5% (95% CI, 55.8–77.2%). The calibration plot showed good agreement between predicted risk and observed incidence of preterm PE, with a slope of 0.983 (95% CI, 0.846–1.120) and an intercept of 0.154 (95% CI, −0.091 to 0.397). Conclusions: The FMF model is effective in predicting preterm PE in the Spanish population at 11–13 weeks' gestation. This method of screening is feasible to implement in routine clinical practice, but it should be accompanied by a robust audit and monitoring system, in order to maintain high‐quality screening. © 2023 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Antecedentes: La exploración ecográfica entre las semanas 11 y 14 tiene un papel fundamental en el cribado de anomalías cromosómicas, siendo la medida de la translucencia nucal un método bien establecido y ampliamente aceptado para este fin. Objetivo: Evaluar retrospectivamente la evolución de los fetos con translucencia nucal aumentada y cariotipo normal. Método: Se recogieron los datos de 104 fetos con TN >percentil 95 (p95) entre las semanas 11 y 14, evaluados en nuestro centro. En los 61 que resultaron eu-ploides, se estudió la incidencia de anomalías estructurales diagnosticadas tanto prenatalmente como tras el nacimiento, así como las pérdidas fetales anteparto. De estos fetos, nacieron sanos el 80% cuando la TN estaba entre p95 y 3,4 mm, el 50% con TN entre 3,5 y 4,4 mm, el 30% con TN entre 4,5 y 5,4 mm, y el 18% con TN > 5,5 mm. Entre los 4 recién nacidos euploides con patología, hubo 3 con cardiopatía. Conclusión: La presencia de TN aumentada entre las 11 -14 semanas en fetos euploides se asocia a un incremento del riesgo de anomalías estructurales mayores, principalmente cardiacas. La prevalencia de malformaciones aumenta significativamente con TN >3,5 mm, y el pronóstico gestacional adverso empeora conforme aumenta la medida de la TN.Background: Ultrasound scan has a main role at the 11-14 weeks screening for chromosomal abnormalities. The measurement of nuchal translucency (NT) thickness is a widespread stablished method to achieve this target. Objective: To assess retrospectively the outcome of fetuses with increased nuchal translucency and normal karyotype. Method: Data were collected from 104 fetuses with NT > 95th percentile at 11 to 14 weeks of gestation, followed in our institution. The sixty one euploid fetuses were studied in order to determine the incidence of structural abnormalities, diagnosed either before or after delivery, as well as antenatal fetal loss. Among these fetuses, there were no malformations at birth in 80% for NT between the 95th percentile and 3.4 mm; 50% for NT between 3.5 and 4.4 mm; 30% for NT of 4.5-5.4 mm; and 18% for NT > 5.5 mm. There were 4 euploid newborns with some kind of structural defect at birth, 3 of them presented a cardiac malformation. Conclusion: The presence of increased NT at 11-14 weeks scan in euploid fetuses it's associated with a higher risk of major structural abnormalities, mainly cardiac ones. The prevalence of malformations is significantly increased for NT > 3.5 mm, and the adverse perinatal outcome is directly associated with the thickness of NT.

Objectives: To compare the performance of three sonographic techniques, the 'reverse-face', 'flipped-face' and 'oblique-face' methods, for visualizing the hard and soft palate in diagnosing cleft lip and palate (CLP). Methods: A total of 60 fetuses (10 with CLP) with a gestational age ranging from 20 to 33 weeks were examined. We compared visualization of the secondary palate with the previously described reverse-face and flipped-face methods (the latter modified by us) and the oblique-face method developed by us using Oblique View imaging technology. Results: Among the 10 fetuses with CLP the defect involved the lip, alveolus and secondary palate in seven, and the primary palate only in the remaining three. The upper lip and alveolar ridge were well visualized in all cases with all three methods. Involvement of the hard palate was diagnosed correctly in 71% (5/7) of the cases using the reverse-face view, in 86% (6/7) with the flipped-face view, and in 100% (7/7) with the oblique-face view; the hard palate was correctly found to be intact in 78%, 84% and 86%, respectively, of the 50 normal fetuses examined with each view. Involvement of the soft palate was diagnosed correctly in only one of the seven fetuses with defects of the secondary palate in flipped-face and oblique-face views, and was correctly considered intact in only 16% of normal fetuses in flipped-face view and in 26% in oblique-face images. Conclusions: Accurate visualization of the soft palate requires an excellent initially acquired volume, fluid between the fetal tongue and palate, and curving of the plane to follow the structure of the palate. The oblique-face or flipped-face views make it possible to visualize the soft palate well in selected cases. [ABSTRACT FROM AUTHOR]

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An abstract of the article "Diagnosis of fetal orofacial clefts in the first trimester: a three-dimensional (3D) ultrasound study," by P. Martinez-Ten and colleagues is presented.

Objectives: The aim of this study is to analyze the impact of the introduction of an internal clinical audit on the cesarean section (CS) rate, evaluated according to the Robson Ten Group Classification System (TGCS), and to identify the main contributors to the overall CS rate in order to plan further interventions., Study Design: In 2014, an internal clinic audit committee was established in our center. Modifications of clinical management protocols were also implemented. A retrospective review of clinical records was conducted and pre-audit (2011-2014) results were compared against audit (2015-2018) results. Patients were clustered according to the Robson TGCS and the analyzed outcomes were CS rate and maternal and neonatal results., Results: Between January 2011 and December 2018, 12,766 women gave birth at our institution among which 2,281 CS were analyzed. After the establishment of the clinical audit, the overall CS rate decreased from 20.27% to 14.82 % (p < 0.01). The major contribution to the overall CS rate in both periods were made by Group 2a (nulliparous with a single cephalic pregnancy at term who underwent labor induction: 4.86 % of all cases), followed by Group 5 (patients with a previous C-section: 3.26 %) and Group 1 (nulliparous with a single cephalic pregnancy at term with spontaneous labor: 2.39 %), representing 59.6 % of all CS. The group that showed the greatest reduction to the overall Cs rate was Group 2 (5.77 % vs 3.96 %, OR 1.48 (p < 0.01). No differences in perinatal and maternal results were found between preaudit and audit group., Conclusion: Audit, feedback, and modification of clinical management protocols may be effective in changing clinical practice and reducing CS rates without worsening maternal and neonatal morbimortality. Robson TGCS allowed us to identify which groups had the greatest impact on CS rate in order to establish new strategies that may lead us to optimize the use of this intervention. It seems that efforts to reduce the overall CS rate should be directed on increasing vaginal birth after CS and reducing CS rates in nulliparous women with single cephalic full-term pregnancy., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this paper, the scientific societies SEGO, SEQC ML and AEDP provide a series of consensus-based recommendations for prenatal screening and diagnosis of genetic abnormalities. A set of evaluation indicators are also proposed as a means to improve the quality of the biochemical, ultrasound, and genetic processes involved in prenatal screening and diagnosis of genetic anomalies. Some recommendations are also proposed in relation to invasive prenatal diagnostic procedures, more specifically regarding sample collection and genetic testing. The purpose of this proposal is to unify performance criteria and quality indicators at national level, with audits performed on a regular basis. It is strongly recommended that a national prenatal screening strategy be established and provided with the resources necessary to evaluate the performance of quality indicators and diagnostic procedures under the supervision of health authorities. Protocols should be revised on a regular basis to consider the incorporation of new cost-effective technologies., Competing Interests: Competing interests: Authors state no conflict of interest., (© 2020 Belén Prieto et al., published by De Gruyter, Berlin/Boston.)

Objective: To present our experience with 14 cases of fetal intracranial hemorrhage (ICH)., Methods: Cases of fetal ICH detected in our institution between 2005 and 2016 by ultrasonography. Maternal characteristics, ultrasound and MRI findings, and postnatal outcome were noted., Results: Twelve cases (86.7%) were identified during a third trimester routine scan at a median gestational age of 30.6 weeks. The ICH was classified as Grade 2 in two cases, Grade 3 in three cases, and Grade 4 in nine cases. Nine cases were bilateral and five were unilateral (four left/one right). The 11 MRI available confirmed grade and location and, in six cases (54.5%), added new findings. There were six terminations of pregnancy, one intrauterine fetal death and seven babies born alive. These were followed up for 28 months (range 3-96). Some grade of neurologic impairment was observed in five children (71.4%, one Grade 3/four Grade 4), mainly mild to moderate motor sequelae., Conclusion: Diagnosis of fetal ICH is amenable to antenatal US. Most of the cases identified are of high grade and usually detected during the third trimester. MRI is a valuable complementary tool in evaluating ICH. Conversely to that previously reported, postnatal survival is high but it entails the risk of adverse neurologic outcome in most neonates.

Objective: The brainstem-vermis angle (BVA) and the brainstem-tentorium angle (BTA) have been proposed to quantify vermian and tentorial alterations associated to fetal posterior fossa malformations. Our objective is to evaluate the intra- and inter-observer agreement for the measurement of these angles during the prenatal ultrasound scan., Methods: Fifteen 3 D sets from fetuses with posterior fossa pathology were processed by multiplanar navigation. Four experts in prenatal ultrasound measured the BVA and the BTA on a mid-sagittal view of the fetal brain, following the criteria described by Volpe. Observer 1 did also repeated measurements following both the criteria by Volpe and Ghi. The intraclass correlation coefficient (ICC) was used to test consistency and absolute agreement for intra- and inter-observer measurements. The concordance is poor when ICC <0.40 and excellent when ICC >0.75., Results: Consistency ICC for measurements between the 4 observers was 0.74 (95% CI: 0.54-0.89) for the BVA and 0.55 (95% CI: 0.29-0.78) for the BTA. Absolute agreement ICC was 0.67 (BVA) and 0.45 (BTA). The intra-observer study showed a significantly greater angle with the criteria by Ghi (mean 52.1°, 95% CI: 49.5-54.8) than with the criteria by Volpe (mean 37.4°, 95% CI: 33.1-41.6)., Conclusions: A more precise methodology for the measurement of these angles should be described.

Objective: This paper aimed to determine the feasibility of identification and measurement reproducibility of intracranial translucency (IT) in our population., Methods: This is a prospective study in which five accredited operators attempted to identify and measure the IT during first-trimester sonographic screening for aneuploidy in 990 fetuses. The presence or absence of spina bifida was determined at the time of the second-trimester scan or after birth. Measurement reproducibility was assessed through intraclass correlation coefficient (ICC) on a subgroup of 150 fetuses., Results: Identification and measurement of the IT were possible in 961 (97%) cases. The mean IT anteroposterior diameter was 1.8 mm (SD ± 0.37; range 0.8-3.1), and the size increased linearly with advancing gestation (IT = 0.74 + 0.02 × crown-rump length; r(2) = 0.15, p < 0.0001). The only fetus with spina bifida in this series presented with absent IT. Intra-observer and inter-observer ICCs were 0.79 and 0.75, respectively (95% confidence intervals 0.72-0.84 and 0.67-0.81, respectively; both p < 0.001)., Conclusions: The IT increases linearly with increasing crown-rump length and seems to be of value in the first-trimester detection of spina bifida. It is easy to identify and measure and shows excellent intra-observer and inter-observer reproducibility measurements., (© 2012 John Wiley & Sons, Ltd.)

Objectives: To determine the feasibility of obtaining adequate 3-dimensional (3D) data sets to examine the fetal secondary palate during the second-trimester anatomy scan., Methods: During a 3-month period, 3D data sets of the fetal secondary palate were obtained from consecutive women undergoing routine second-trimester scans. Only structurally normal singleton fetuses with a normal upper lip on 2-dimensional (2D) sonography were included. Three-dimensional data sets were obtained using a mechanical transducer with a 45° sweep and the same settings as for the standard 2D scan, ideally when the fetus was facing the transducer, with mild extension of the head, and the ultrasound beams projecting caudally to cranially to avoid shadowing from the primary palate or mandible. No additional scanning time was allocated for examination of the palate. Acquired 3D data sets were analyzed offline using dedicated software, and the secondary palate was assessed using the "flipped face" technique., Results: Ninety-seven women met entry criteria and underwent second-trimester scans at a median gestational age of 22 completed weeks (range, 18-23 weeks). In 13 (13.4%) cases, it was not possible to obtain a midsagittal view of the face for capturing 3D volume data sets due to fetal position. Additional factors limiting visualization were shadowing from the primary palate in fetuses with flexion of the head in 30 (30.9%) cases, interposition of, or shadowing from, fetal arms or legs in 11 (11.3%), inability to reproduce a true midsagittal plane in 8 (8.2%), and poor image quality in 1 (1%). Therefore, it was only possible to assess the secondary palate in 34 (35.1%) cases., Conclusions: It is not feasible to obtain adequate 3D data sets for offline analysis of the fetal secondary palate in almost two-thirds of second-trimester fetuses during the routine scan. However, suboptimal visualization is primarily due to factors related to fetal position rather than equipment or image quality. This finding suggests that a dedicated scan, during which adequate time can be devoted to obtaining a satisfactory position in which the fetal face can be evaluated, may be warranted in high-risk cases.

Objectives: The purpose of this study was to assess the diagnostic accuracy and infant outcomes of antenatally detected renal duplex anomalies., Methods: An observational longitudinal study of cases of renal duplex anomalies diagnosed on prenatal sonography was conducted. Information on the prenatal sonographic findings, antenatal course, and perinatal outcome was obtained by reviewing the sonography reports and delivery records. Postnatal follow-up, including neonatal and infant evaluations, was obtained from hospital records., Results: During a 7-year period, a total of 24 cases of renal duplex anomalies were identified prenatally. Three cases were excluded from subsequent analysis because of termination of pregnancy after the diagnosis of a severe brain abnormality, loss to follow-up, and an inability to confirm the prenatal diagnosis on neonatal renal sonography. Among the 21 confirmed cases, the presence of two separate renal pelvises was the most common prenatal sonographic feature (n = 15 [71%]), followed by dilatation of a single moiety with a dilated ipsilateral ureter or ureterocele (n = 6 [29%]). In 43% of cases, the renal duplex anomalies had no adverse associations, but in 48%, they were complicated by a urinary tract infection, and 48% of the infants required a surgical procedure during early childhood., Conclusions: Renal duplex anomalies can be accurately diagnosed by prenatal sonography even when there is minimal dilatation of the renal pelvis. Antenatal diagnosis allows planning of postnatal care, which may prevent urinary tract infections and renal function impairment. The natural history of antenatally diagnosed duplex anomalies seems to be overall benign, with urinary tract infections and the need for surgery being the most common complications in affected infants.

Objective: The purpose of this study was to evaluate a new sonographic technique for identifying the nasal bones using the retronasal triangle view, ie, the coronal plane at which the palate and frontal processes of the maxilla are simultaneously visualized., Methods: Three-dimensional (3D) volumes were acquired from women undergoing first-trimester sonographic screening for aneuploidy by 2 accredited operators. Those data sets in which the fetal face was clearly identified were selected for offline analysis by 2 other observers who were unaware of the sonographic or clinical findings. The nasal bones were classified as both present, only 1 present (right or left), or absent according to the presence or absence of 2 small paired echogenic linear structures at the upper tip of the retronasal triangle as determined by 3D navigation in the coronal plane and compared to those findings obtained by 3D navigation in the sagittal plane. Additional 3D data sets involving a subset of 4 first-trimester fetuses with trisomy 21 and absent nasal bones were also analyzed retrospectively and included randomly in the study group., Results: A total of 110 3D data sets were analyzed, of which 86% were obtained transabdominally and 14% transvaginally. The quality of nasal bone identification was classified subjectively by the observers as good in 67% of cases, fair in 29%, and poor in 4%. The nasal bones were classified as at least 1 present in 106 of the cases (96%) and absent in 4 (4%), with complete agreement between observers in both the sagittal and coronal planes (κ = 1). Discrimination between the right and left nasal bones was possible in 89% and 93% for observer A and in 96% and 96% for observer B by assessing the sagittal and coronal views, respectively (right nasal bone: κ = 0.90 [95% confidence interval (CI), 0.79-1]; left nasal bone: κ = 0.85 [95% CI, 0.60-0.99]). The nasal bones were not identified at the level of the retronasal triangle view in any of the fetuses with trisomy 21 and absent nasal bones., Conclusions: This study shows that the nasal bones can be confidently identified as paired echogenic structures located at the upper tip of the retronasal triangle. This coronal view of the fetal face offers the possibility of screening for the presence or absence of the nasal bones in the first trimester, especially when the standard midsagittal views of the fetal face are suboptimal because of fetal or maternal factors. Because both nasal bones can be evaluated simultaneously in the coronal plane, the retronasal triangle view may be advantageous over the conventional midsagittal view assessment, in which only 1 of the 2 nasal bones is evaluated.