Reference ranges for fetal brain structures using magnetic resonance imaging: systematic review

[Prenatal imaging - role of fetal MRI]

Congenital abnormalities occur in about 3 in 100 fetuses. Prenatal ultrasound is the standard technique to detect these fetal abnormalities. In Germany, three ultrasound examinations are provided in the first, second, and third trimesters, respectively. Fetal magnetic resonance imaging (MRI) can be used as an adjunct technique to provide further information in cases of congenital abnormalities.A literature search was performed on PubMed focusing on publications that used fetal MRI as a secondary approach after prenatal ultrasound.MRI is a safe imaging method that does not harm the fetus when used during pregnancy. Some publications with experts in radiology show a very clear diagnostic advantage with respect to performing MRI on fetuses with brain abnormalities, while other publications with experts in neurosonography do not find the advantage to be that evident. Both techniques are clearly user-dependent.Fetal MRI can supplement the information obtained by fetal ultrasound and can provide additional information or exclude others. Diagnosis made by an interdisciplinary cooperation based on all available ultrasound and MRI findings is the key to optimal imaging and advice for expectant parents. · Fetal MRI poses no risk for the fetus.. · MRI aids prenatal ultrasound in the evaluation of prenatal findings.. · Tavares de Sousa M, Schönnagel BP, Denecke J et al. Prenatal imaging - role of fetal MRI. Fortschr Röntgenstr 2025; 197: 385-396.

Prenatal assessment of brain malformations on neuroimaging: an expert panel review

Brain malformations represent a heterogeneous group of abnormalities of neural morphogenesis, often associated with aberrations of neuronal connectivity and brain volume. Prenatal detection of brain malformations requires a clear understanding of embryology and developmental morphology through the various stages of gestation. This expert panel review is written with the central aim of providing an easy-to-understand road map to improve prenatal detection and characterization of structural malformations based on the current understanding of normal and aberrant brain development. For every developmental stage, the utility of each available neuroimaging modality, including prenatal multiplanar neuro sonography, anatomical MRI and advanced MRI techniques, as well as further insights from post-mortem imaging, has been highlighted.

Lung volumes are increased in fetuses with transposition of the great arteries on intrauterine MRI

Fetal brain size is decreased in some children with complex CHDs, and the distribution of blood and accompanying oxygen and nutrients is regionally skewed from early fetal life dependent on the CHD. In transposition of the great arteries, deoxygenated blood preferentially runs to the brain, whereas the more oxygenated blood is directed towards the lungs and the abdomen. Knowledge of whether this impacts intrauterine organ development is limited. We investigated lung, liver, and total intracranial volume in fetuses with transposition of the great arteries using MRI.Eight fetuses with dextro-transposition and without concomitant disease or chromosomal abnormalities and 42 fetuses without CHD or other known diseases were scanned once or twice at gestational age 30 through 39 weeks. The MRI scans were conducted on a 1.5T system, using a 2D balanced steady-state free precession sequence. Slices acquired covered the entire fetus, slice thickness was 10 mm, pixel size 1.5 × 1.5 mm, and scan duration was 30 sec.The mean lung z score was significantly larger in fetuses with transposition compared with those without a CHD; mean difference is 1.24, 95% CI:(0.59;1.89), p < 0.001. The lung size, corrected for estimated fetal weight, was larger than in the fetuses without transposition; mean difference is 8.1 cm3/kg, 95% CI:(2.5;13.7 cm3/kg), p = 0.004.In summary, fetuses with dextro-transposition of the great arteries had both absolute and relatively larger lung volumes than those without CHD. No differences were seen in liver and total intracranial volume. Despite the small number of cases, the results are interesting and warrant further investigation.

Automated Craniofacial Biometry with 3D T2w Fetal MRI

Objectives

Evaluating craniofacial phenotype-genotype correlations prenatally is increasingly important; however, it is subjective and challenging with 3D ultrasound. We developed an automated landmark propagation pipeline using 3D motion-corrected, slice-to-volume reconstructed (SVR) fetal MRI for craniofacial measurements.

Methods

A literature review and expert consensus identified 31 craniofacial biometrics for fetal MRI. An MRI atlas with defined anatomical landmarks served as a template for subject registration, auto-labelling, and biometric calculation. We assessed 108 healthy controls and 24 fetuses with Down syndrome (T21) in the third trimester (29-36 weeks gestational age, GA) to identify meaningful biometrics in T21. Reliability and reproducibility were evaluated in 10 random datasets by four observers.

Results

Automated labels were produced for all 132 subjects with a 0.03% placement error rate. Seven measurements, including anterior base of skull length and maxillary length, showed significant differences with large effect sizes between T21 and control groups (ANOVA, p<0.001). Manual measurements took 25-35 minutes per case, while automated extraction took approximately 5 minutes. Bland-Altman plots showed agreement within manual observer ranges except for mandibular width, which had higher variability. Extended GA growth charts (19-39 weeks), based on 280 control fetuses, were produced for future research.

Conclusion

This is the first automated atlas-based protocol using 3D SVR MRI for fetal craniofacial biometrics, accurately revealing morphological craniofacial differences in a T21 cohort. Future work should focus on improving measurement reliability, larger clinical cohorts, and technical advancements, to enhance prenatal care and phenotypic characterisation.

Assessment of fetal corpus callosum biometry by 3D super-resolution reconstructed T2-weighted magnetic resonance imaging

Objective

To assess the accuracy of corpus callosum (CC) biometry, including sub-segments, using 3D super-resolution fetal brain MRI (SR) compared to 2D or 3D ultrasound (US) and clinical low-resolution T2-weighted MRI (T2WS).

Method

Fetal brain biometry was conducted by two observers on 57 subjects [21-35 weeks of gestational age (GA)], including 11 cases of partial CC agenesis. Measures were performed by a junior observer (obs1) on US, T2WS and SR and by a senior neuroradiologist (obs2) on T2WS and SR. CC biometric regression with GA was established. Statistical analysis assessed agreement within and between modalities and observers.

Results

This study shows robust SR to US concordance across gestation, surpassing T2WS. In obs1, SR aligns with US, except for genu and CC length (CCL), enhancing splenium visibility. In obs2, SR closely corresponds to US, differing in rostrum and CCL. The anterior CC (rostrum and genu) exhibits higher variability. SR's regression aligns better with literature (US) for CCL, splenium and body than T2WS. SR is the method with the least missing values.

Conclusion

SR yields CC biometry akin to US (excluding anterior CC). Thanks to superior 3D visualization and better through plane spatial resolution, SR allows to perform CC biometry more frequently than T2WS.

Too short or too long: impact of corpus callosal measurement on prenatal counseling

Linked article: This Correspondence comments on Corroenne et al. Click here to view the article.

Automatic biometry of fetal brain MRIs using deep and machine learning techniques

Linear biometric measurements on magnetic resonance images are important for the assessment of fetal brain development, which is expert knowledge dependent and laborious. This study aims to construct a segmentation-based method for automatic two-dimensional biometric measurements of fetal brain on magnetic resonance images that provides a fast and accurate measurement of fetal brain. A total of 268 volumes (5360 images) magnetic resonance images of normal fetuses were included. The automatic method involves two steps. First, the fetal brain was segmented into four parts with a deep segmentation network: cerebrum, cerebellum, and left and right lateral ventricles. Second, the measurement plane was determined, and the corresponding biometric parameters were calculated according to clinical guidelines, including cerebral biparietal diameter (CBPD), transverse cerebellar diameter (TCD), left and right atrial diameter (LAD/RAD). Pearson correlation coefficient and Bland-Altman plots were used to assess the correlation and agreement between computer-predicted values and manual measurements. Mean differences were used to evaluate the errors quantitatively. Analysis of fetal cerebral growth based on the automatic measurements was also displayed. The experiment results show that correlation coefficients for CBPD, TCD, LAD and RAD were as follows: 0.977, 0.990, 0.817, 0.719, mean differences were - 2.405 mm, - 0.008 mm, - 0.33 mm, - 0.213 mm, respectively. The correlation between the errors and gestational age was not statistically significant (p values were 0.2595, 0.0510, 0.1995, and 0.0609, respectively). The proposed automatic method for linear measurements on fetal brain MRI achieves excellent performance, which is expected to be applied in clinical practice and be helpful for prenatal diagnosis and clinical work efficiency improvement.

Effect of magnet strength on fetal brain biometry - a single-center retrospective MRI-based cohort study

PURPOSE

Abnormal fetal brain measurements might affect clinical management and parental counseling. The effect of between-field-strength differences was not evaluated in quantitative fetal brain imaging until now. Our study aimed to compare fetal brain biometry measurements in 3.0 T with 1.5 T scanners.

METHODS

A retrospective cohort of 1150 low-risk fetuses scanned between 2012 and 2021, with apparently normal brain anatomy, were retrospectively evaluated for biometric measurements. The cohort included 1.5 T (442 fetuses) and 3.0 T scans (708 fetuses) of populations with comparable characteristics in the same tertiary medical center. Manually measured biometry included bi-parietal, fronto-occipital and trans-cerebellar diameters, length of the corpus-callosum, vermis height, and width. Measurements were then converted to centiles based on previously reported biometric reference charts. The 1.5 T centiles were compared with the 3.0 T centiles.

RESULTS

No significant differences between centiles of bi-parietal diameter, trans-cerebellar diameter, or length of the corpus callosum between 1.5 T and 3.0 T scanners were found. Small absolute differences were found in the vermis height, with higher centiles in the 3.0 T, compared to the 1.5 T scanner (54.6th-centile, vs. 39.0th-centile, p < 0.001); less significant differences were found in vermis width centiles (46.9th-centile vs. 37.5th-centile, p = 0.03). Fronto-occipital diameter was higher in 1.5 T than in the 3.0 T scanner (66.0th-centile vs. 61.8th-centile, p = 0.02).

CONCLUSIONS

The increasing use of 3.0 T MRI for fetal imaging poses a potential bias when using 1.5 T-based charts. We elucidate those biometric measurements are comparable, with relatively small between-field-strength differences, when using manual biometric measurements. Small inter-magnet differences can be related to higher spatial resolution with 3 T scanners and may be substantial when evaluating small brain structures, such as the vermis.

Corpus callosal reference ranges: systematic review of methodology of biometric chart construction and measurements obtained

OBJECTIVE

Adequate reference ranges of size of the corpus callosum (CC) are necessary to improve characterization of CC abnormalities and parental counseling. The objective of this study was to evaluate the methodology used in studies developing references charts for CC biometry.

METHODS

We conducted a systematic review of studies on fetal CC biometry using a set of predefined quality criteria of study design, statistical analysis and reporting methods. We included observational studies whose primary aim was to create ultrasound or magnetic resonance imaging charts for CC size in a normal population of fetuses. Studies were scored against a predefined set of independently agreed methodological criteria, and an overall quality score was given for each study.

RESULTS

Twelve studies met the inclusion criteria. Quality scores ranged between 17.4% and 95.7%. The greatest potential for bias was noted for the following items: sample selection and sample-size calculation, as only 17% of the studies were population-based and had consecutive or random recruitment of patients and with a justification of the sample size; number of measurements obtained for CC biometry, as only 17% of the studies performed more than one measurement per fetus and per scan; and description of characteristics of the study population, as only 8% of the studies clearly reported a minimum dataset of demographic characteristics.

CONCLUSIONS

Our review demonstrates substantial heterogeneity in methods and final biometric values of the fetal CC across the evaluated studies. The use of uniform methodology of the highest quality is essential in order to define a 'short' CC and provide appropriate parental counseling. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Should we expand indications for targeted fetal neurosonography?

Linked article: This Correspondence comments on Paules et al. Click here to view the article

Role of prenatal magnetic resonance imaging in fetuses with isolated severe ventriculomegaly at neurosonography: A multicenter study

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 (

RESULTS

187 fetuses with a prenatal diagnosis of isolated severe ventriculomegaly on neurosonography were included in the analysis. Additional structural anomalies were detected exclusively at prenatal MRI in 18.1% of cases. When considering the type of anomaly, malformations of cortical development were detected on MRI in 32.4% cases, while midline or acquired (hypoxemic/hemorrhagic) lesions were detected in 26.5% and 14.7% of cases, respectively. There was no difference in the rate of additional anomalies when stratifying the analysis according to either gestational age at MRI or laterality of the lesion. At multivariate logistic regression analysis, the presence of additional anomalies only found at MRI was significantly higher in bilateral compared versus unilateral ventriculomegaly (OR: 4.37, 95% CI 1.21-15.76; p = 0.04), while neither maternal body mass index, age, severity of ventricular dilatation, interval between ultrasound and MRI, nor gestational age at MRI were associated with the likelihood of detecting associated anomalies at MRI.

CONCLUSION

The rate of associated anomalies detected exclusively at prenatal MRI in fetuses with isolated severe ventriculomegaly is lower than previously reported, but higher compared to isolated mild and moderate ventriculomegaly. Fetal MRI should be considered as a part of the prenatal assessment of fetuses presenting with isolated severe ventriculomegaly at neurosonography.

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Key Words

• Central nervous system
• Fetal magnetic resonance imaging
• Fetal ultrasound
• MRI
• Neurosonography
• Prenatal diagnosis
• Ventriculomegaly

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MESH Headings

• Cohort Studies
• Female
• Fetus
• Humans
• Hydrocephalus/diagnostic imaging
• Magnetic Resonance Imaging
• Pregnancy
• Prenatal Diagnosis
• Retrospective Studies
• Ultrasonography, Prenatal

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Affiliation(s)

Daniele Di Mascio Department of Maternal and Child Health and Urological Sciences, Sapienza University of Rome, Italy
Asma Khalil Fetal Medicine Unit, Saint George's Hospital, London, United Kingdom; Vascular Biology Research Centre, Molecular and Clinical Sciences Research Institute, St George's University of London, United Kingdom
Gianluigi Pilu Unit of Obstetrics, Department of Medical and Surgical Sciences, University of Bologna, Italy
Giuseppe Rizzo Division of Maternal and Fetal Medicine, Ospedale Cristo Re, University of Rome Tor Vergata, Rome, Italy; Department of Obstetrics and Gynecology The First I.M. Sechenov Moscow State Medical University, Moscow, Russia
Massimo Caulo Department of Neuroscience, Imaging and Clinical Sciences, Institute for Advanced Biomedical Technologies, "G. D'Annunzio" University of Chieti, Italy
Marco Liberati Centre for Fetal Care and High-risk Pregnancy, Department of Obstetrics and Gynecology, University of Chieti, Italy
Antonella Giancotti Department of Maternal and Child Health and Urological Sciences, Sapienza University of Rome, Italy
Christoph Lees Department of Surgery and Cancer, Institute of Reproductive and Developmental Biology, Imperial College London, United Kingdom; Centre for Fetal Care, Queen Charlotte's and Chelsea Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom
Paolo Volpe Fetal Medicine Unit, Di Venere and Sarcone Hospitals, Bari, Italy
Danilo Buca Centre for Fetal Care and High-risk Pregnancy, Department of Obstetrics and Gynecology, University of Chieti, Italy
Ludovica Oronzi Centre for Fetal Care and High-risk Pregnancy, Department of Obstetrics and Gynecology, University of Chieti, Italy
Alice D'Amico Centre for Fetal Care and High-risk Pregnancy, Department of Obstetrics and Gynecology, University of Chieti, Italy
Sara Tinari Centre for Fetal Care and High-risk Pregnancy, Department of Obstetrics and Gynecology, University of Chieti, Italy
Tamara Stampalija Unit of Fetal Medicine and Prenatal Diagnosis, Institute for Maternal and Child Health IRCCS Burlo Garofolo, Trieste, Italy; Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
Ilaria Fantasia Unit of Fetal Medicine and Prenatal Diagnosis, Institute for Maternal and Child Health IRCCS Burlo Garofolo, Trieste, Italy
Lucia Pasquini Fetal Medicine Unit, Department for Women and Children Health, AOU Careggi, Florence, Italy
Giulia Masini Fetal Medicine Unit, Department for Women and Children Health, AOU Careggi, Florence, Italy
Roberto Brunelli Department of Maternal and Child Health and Urological Sciences, Sapienza University of Rome, Italy
Valentina D'Ambrosio Department of Maternal and Child Health and Urological Sciences, Sapienza University of Rome, Italy
Ludovico Muzii Department of Maternal and Child Health and Urological Sciences, Sapienza University of Rome, Italy
Lucia Manganaro Department of Radiology, Anatomo-Pathology and Oncology, Sapienza University of Rome, Italy
Amanda Antonelli Department of Radiology, Anatomo-Pathology and Oncology, Sapienza University of Rome, Italy
Giada Ercolani Department of Radiology, Anatomo-Pathology and Oncology, Sapienza University of Rome, Italy
Sandra Ciulla Department of Radiology, Anatomo-Pathology and Oncology, Sapienza University of Rome, Italy
Gabriele Saccone Department of Neuroscience, Reproductive Sciences and Dentistry, School of Medicine, Federico II University of Naples, Italy
Giuseppe Maria Maruotti Department of Neuroscience, Reproductive Sciences and Dentistry, School of Medicine, Federico II University of Naples, Italy
Luigi Carbone Department of Neuroscience, Reproductive Sciences and Dentistry, School of Medicine, Federico II University of Naples, Italy
Fulvio Zullo Department of Neuroscience, Reproductive Sciences and Dentistry, School of Medicine, Federico II University of Naples, Italy
Claudiana Olivieri Fetal Medicine Unit, Di Venere and Sarcone Hospitals, Bari, Italy
Tullio Ghi Department of Medicine and Surgery, Unit of Surgical Sciences, Obstetrics and Gynecology, University of Parma, Italy
Tiziana Frusca Department of Medicine and Surgery, Unit of Surgical Sciences, Obstetrics and Gynecology, University of Parma, Italy
Andrea Dall'Asta Department of Surgery and Cancer, Institute of Reproductive and Developmental Biology, Imperial College London, United Kingdom; Centre for Fetal Care, Queen Charlotte's and Chelsea Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom; Department of Medicine and Surgery, Unit of Surgical Sciences, Obstetrics and Gynecology, University of Parma, Italy
Silvia Visentin Department of Woman' and Child's Health, University of Padova, Padova, Italy
Erich Cosmi Department of Woman' and Child's Health, University of Padova, Padova, Italy
Francesco Forlani Department of Obstetrics and Gynaecology, Arnas Civico Hospital, Palermo, Italy
Alberto Galindo Fetal Medicine Unit, Maternal and Child Health and Development Network, University Hospital 12 de Octubre, Complutense University of Madrid, Department of Obstetrics and Gynaecology, Madrid, Spain
Cecilia Villalain Fetal Medicine Unit, Maternal and Child Health and Development Network, University Hospital 12 de Octubre, Complutense University of Madrid, Department of Obstetrics and Gynaecology, Madrid, Spain
Ignacio Herraiz Fetal Medicine Unit, Maternal and Child Health and Development Network, University Hospital 12 de Octubre, Complutense University of Madrid, Department of Obstetrics and Gynaecology, Madrid, Spain
Filomena Giulia Sileo Fetal Medicine Unit, Saint George's Hospital, London, United Kingdom; Department of Biochemical, Metabolic and Neural Sciences, International Doctorate School in Clinical and Experimental Medicine, University of Modena and Reggio Emilia, Modena, Italy; Unit of Obstetrics and Gynecology, Azienda Unità Sanitaria Locale - IRCCS, Reggio Emilia, Italy
Olivia Mendez Quintero Fetal Medicine Unit, Saint George's Hospital, London, United Kingdom
Ginevra Salsi Unit of Obstetrics, Department of Medical and Surgical Sciences, University of Bologna, Italy
Gabriella Bracalente Fetal Medicine Unit, Department of Obstetrics and Gynecology, Osp. Cà Foncello Treviso, Italy
José Morales-Roselló Servicio de Obstetricia, Hospital Universitario y Politécnico La Fe, Valencia, Spain; Departamento de Pediatría Obstetricia y Ginecología, Universidad de Valencia, Spain
Gabriela Loscalzo Servicio de Obstetricia, Hospital Universitario y Politécnico La Fe, Valencia, Spain; Departamento de Pediatría Obstetricia y Ginecología, Universidad de Valencia, Spain
Marcella Pellegrino Department of Woman, Child Health and Public Health, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy
Marco De Santis Department of Woman, Child Health and Public Health, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy
Antonio Lanzone Department of Woman, Child Health and Public Health, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy
Cecilia Parazzini Pediatric Radiology and Neuroradiology Department, Children's Hospital V. Buzzi, Università di Milano, Italy
Mariano Lanna Fetal Therapy Unit 'Umberto Nicolini', Children's Hospital, V. Buzzi Università di Milano, Italy
Francesca Ormitti Department of Radiology - Azienda Ospedaliera Universitaria di Parma, Italy
Francesco Toni IRCCS Istituto delle Scienze Neurologiche UOC Neuroradiologia, Bologna, Italy
Flora Murru Unit of Paediatric Radiology, Institute for Maternal and Child Health IRCCS Burlo Garofolo, Italy
Marco Di Maurizio UOC Radiodiagnostica, AOU Meyer, Florence, Italy
Elena Trincia UOC Neuroradiologia, Osp. Cà Foncello Treviso, Italy
Raquel Garcia Complejo Hospitalario Universitario Insular - Materno Infantil de Canarias, Las Palmas de Gran Canaria, Spain
Olav Bennike Bjørn Petersen Center for Fetal Medicine and Ultrasound, Department of Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark; Department of Clinical Medicine, University of Copenhagen, Denmark
Lisa Neerup Center for Fetal Medicine and Ultrasound, Department of Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
Puk Sandager Center for Fetal Medicine, Department of Obstetrics and Gynecology, Aarhus University Hospital, Aarhus, Denmark; Institute for Clinical Medicine, Aarhus University, Aarhus, Denmark
Federico Prefumo Division of Obstetrics and Gynecology, Department of Clinical and Experimental Sciences, University of Brescia, Italy
Lorenzo Pinelli Neuroradiology Unit, Pediatric Neuroradiology Section, ASST Spedali Civili, Brescia, Italy
Ilenia Mappa Division of Maternal and Fetal Medicine, Ospedale Cristo Re, University of Rome Tor Vergata, Rome, Italy
Cecilia Acuti Martellucci Department of Medical Sciences, University of Ferrara, Italy
Maria Elena Flacco Department of Medical Sciences, University of Ferrara, Italy
Lamberto Manzoli Department of Medical Sciences, University of Ferrara, Italy
Ilaria Giangiordano Department of Child and Adolescent Neuropsychiatry, Local Health Unit of Avezzano-Sulmona-L'Aquila, Sulmona, Italy
Luigi Nappi Fetal Medicine Unit, Department of Medical and Surgical Sciences, University of Foggia, Italy
Giovanni Scambia Department of Woman, Child Health and Public Health, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy
Vincenzo Berghella Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, USA
Francesco D'Antonio Centre for Fetal Care and High-risk Pregnancy, Department of Obstetrics and Gynecology, University of Chieti, Italy.

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