Trimester Fetuses Research Articles

VP20.03: Search for fetal venous anomalies in mid‐trimester scan

Aim of the study was to identify anomalies of fetal venous system during routine second trimester scan using standard anatomical sections. We examined second trimester fetuses between January 2017 to May 2021. We studied the fetal veins especially the pulmonary veins, SVC, IVC, brachiocephalic, umbilical and portal veins. We studied veins in axial plane at root of neck, axial three vessel view, axial section at the level of stomach bubble and portal sinus, axial section at the level of umbilical vein insertion and sagittal section demonstrating SVC, IVC and right atrium. 20 out of 1700 second trimester fetuses had variations in venous anatomy. 10 fetuses had persistent left superior vena cava, six had persistent right umbilical vein, one had anomalous pulmonary venous drainage, one had interrupted IVC with azygos continuation, one had an intrathymic course of brachiocephalic vein and one had umbilical varix. In persistent left SVC group, one fetus had Choroid plexus cysts, one had right atrial isomerism, one had hypoplastic left ventricle, hemivertebra, pelvicaliectasis and ventriculomegaly. One fetus in the group was showing features of growth restriction. In the persistent right umbilical vein group and in fetus with intrathymic brachiocephalic vein, we did not find any associated anomaly. Fetus with umbilical varix had chorioangioma of the placenta. Fetal venous anomalies are rare group of anomalies. Routine search for venous anatomical variations during mid trimester can be a clue for other associated anomalies. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Analysis of maturation features in fetal brain ultrasound via artificial intelligence for the estimation of gestational age

Optimal prenatal care relies on accurate gestational age dating. After the first trimester, the accuracy of current gestational age estimation methods diminishes with increasing gestational age. Considering that, in many countries, access to first trimester crown rump length is still difficult owing to late booking, infrequent access to prenatal care, and unavailability of early ultrasound examination, the development of accurate methods for gestational age estimation in the second and third trimester of pregnancy remains an unsolved challenge in fetal medicine. This study aimed to evaluate the performance of an artificial intelligence method based on automated analysis of fetal brain morphology on standard cranial ultrasound sections to estimate the gestational age in second and third trimester fetuses compared with the current formulas using standard fetal biometry. Standard transthalamic axial plane images from a total of 1394 patients undergoing routine fetal ultrasound were used to develop an artificial intelligence method to automatically estimate gestational age from the analysis of fetal brain information. We compared its performance-as stand alone or in combination with fetal biometric parameters-against 4 currently used fetal biometry formulas on a series of 3065 scans from 1992 patients undergoing second (n=1761) or third trimester (n=1298) routine ultrasound, with known gestational age estimated from crown rump length in the first trimester. Overall, 95% confidence interval of the error in gestational age estimation was 14.2 days for the artificial intelligence method alone and 11.0 when used in combination with fetal biometric parameters, compared with 12.9 days of the best method using standard biometrics alone. In the third trimester, the lower 95% confidence interval errors were 14.3 days for artificial intelligence in combination with biometric parameters and 17 days for fetal biometrics, whereas in the second trimester, the 95% confidence interval error was 6.7 and 7, respectively. The performance differences were even larger in the small-for-gestational-age fetuses group (14.8 and 18.5, respectively). An automated artificial intelligence method using standard sonographic fetal planes yielded similar or lower error in gestational age estimation compared with fetal biometric parameters, especially in the third trimester. These results support further research to improve the performance of these methods in larger studies.

Increased nuchal translucency after low-risk noninvasive prenatal testing: What should we tell prospective parents?

Three decades ago, the observation that first trimester fetuses with excess fluid accumulation at the back of the neck were more likely to be aneuploid, gave rise to a new era of prenatal screening. The nuchal translucency (NT) measurement in combination with serum biomarkers and maternal age, resulted in the first trimester combined screening (FTCS) program. The introduction of noninvasive prenatal testing (NIPT) over the past decade has introduced the option for parents to receive highly sensitive and specific screening information for common trisomy from as early as 10weeks gestation, altering the traditional pathway FTCS pathway. The retention of the 11-13-week NT ultrasound remains important in the detection of structural anomalies; however, the optimal management of pregnancies with a low-risk NIPT result and an isolated increased NT measurement in an era of advanced genomic testing options is a new dilemma for clinicians. For parents, the prolonged period between the initial diagnosis in first trimester, and prognostic information at each successive stage of investigations up to 22-24weeks, can be emotionally challenging. This article addresses the common questions from parents and clinicians as they navigate the uncertainty of having a fetus diagnosed with an increased NT after a low-risk NIPT result and presents suggested approaches to management.

Analysis of families with fetal congenital abnormalities but negative prenatal diagnosis by whole exome sequencing

Objective: To evaluate the value of whole exome sequencing (WES) in prenatal clinical application. Methods: A total of 1 152 cases of congenital abnormal [including structural malformation, nuchal translucency (NT) thickening and intrauterine growth restriction] with traditional prenatal diagnosis [including G-band karyotype analysis and chromosome microarray analysis (CMA)] negative were analyzed. The congenital abnormal fetuses were divided into retrospective group and prospective group according to the time of WES detection, that is whether the pregnancy termination or not. According to the specific location of fetal malformation and their family history, the cohort was divided into subgroups. The clinical prognosis of all fetuses were followed up, and the effect of WES test results on pregnancy decision-making and clinical intervention were analyzed. According to the follow-up results, the data of fetuses with new phenotypes in the third trimester or after birth were re-analyzed. Results: Among 1 152 families who received WES, 5 families were excluded because of nonbiological parents. Among the remaining 1 147 families, 152 fetuses obtained positive diagnosis (13.3%,152/1 147), including 74 fetuses in the retrospective group (16.1%,74/460) and 78 fetuses in the prospective group (11.4%,78/687). In fetuses with negative CMA and G-band karyotype analysis results but new phenotypes in the third trimester or after birth, the positive rate by WES data re-analysis was 4.9% (8/163). A total of 34 (21.3%, 34/160) fetuses were directly affected by the corresponding positive molecular diagnosis. Among 68 cases of live births with diagnostic variation grade 4, 29 cases (42.7%, 29/68) received appropriate medical intervention through rapid review of WES results. Conclusions: WES could increase the detection rate of abnormal fetuses with negative G-banding karyotype analysis and CMA by 13.3%. Prenatal WES could guide pregnancy decision-making and early clinical intervention. It might be an effective strategy to pay attention to the special follow-up of the third trimester and postnatal fetus and to re-analyze the WES data.

Fetal development and growth of the fissula ante fenestram in the human ear.

Since the fissula ante fenestram (FAF) is considered as a focus of otosclerotic lesion and a route of perilymph leakage, there are few description of prenatal development of the cartilaginous canal passing though the cochlear wall. We examined the sagittal and frontal histological sections of the ear from 32 human fetuses at 8-37 weeks of gestational age. At 8-12 weeks, in the immediately anterior side of a connection between the cochlear and canalicular parts of the otic capsule cartilage, the FAF appeared as a tear of a cartilage between the basal and second turns of the cochlea. The tear became a slit opening to the scala vestibuli. At 13-15 weeks, the FAF, less than 1.2 mm in length, had the anterosuperior and postero-inferior apertures: the former was near the geniculate ganglion and became closed after 15 weeks, while the latter approached the oval window. Third trimester fetuses, the FAF, 1.5-2.0 mm in length, consistently carried a single, postero-inferior aperture extending along the anterior margin of the oval window and it contained no definite epithelium and vessel. Although it was endochondral ossification, there was no clear zonation in cartilage cells of the FAF. A mechanical stress during three-dimensional coiling of the cochlear ducts seemed to provide the FAF. After the FAF was established, the stapes footplate might use a part of the inferior aperture for the syndesmosis. A specific ossification was seen in the FAF, but it might rarely cause the pathological syndesmosis.

ULTRASOUND MEASUREMENT OF TRANSCEREBELLAR DIAMETER (TCD)/ABDOMINAL CIRCUMFERENCE (AC) RATIO IN NORMAL AND GROWTH RESTRICTED FETUSES ABOVE TWENTY WEEKS OF GESTATION

Background: Intrauterine growth retardation (IUGR) is an obstetrical syndrome that is generally associated with increased mortality and morbidity. In IUGR, maternal placental blood flow is extremely compromised and that worsen the inter-villous circulation leading to an end-stage fetal distress. Objective: To compare TCD/AC ratio in both normal and growth restricted fetuses in second and third trimesters and to find if there is any correlation between TCD/AC ratio and EFW. Patients and methods: The study was conducted on 100 singleton pregnant women at EL-Sayed Galal University Hospital and Damanhour Teaching Hospital in the period between March 2019 till May 2020 and the patients were divided into two main equal groups. Group I included pregnant females with normally growing fetuses and Group II included pregnant females with growth restricted fetuses above 20 weeks of gestation. Results: This study demonstrated the usefulness of the single cut-off value (13.75%) of the TCD/AC ratio which may contribute to the early identification of SGA infants. The problem lied in identifying the process at the onset or before the IUGR has become severe. Usually the first parameter to decrease is the fetal AC due to depletion of hepatic glycogen and subcutaneous fat stores. The TCD/AC ratio, which utilized a single cut-off value (13.75%) independent of GA, improved diagnostic sensitivity and specificity in these cases. The possible contribution of the TCD/AC ratio in identifying the fetal growth failure itself, which was more important than predicting weight at birth to be further evaluated. There was no correlation between TCD/AC ratio and EFW and no statistical significant correlation between TCD/AC ratio and UA Doppler. Conclusion: In IUGR fetuses, the fetal TCD was less affected than fetal head circumference (HC) suggesting preferential preservation of cerebellar growth relative to other cranial structures. The TCD/AC ratio was helpful in recognizing abnormal fetal growth even when the GA was uncertain since this ratio was gestational age-independent.

Epidemiology of Pregnancy Complications Through the Lens of Immunological Memory.

In the fifteen minutes it takes to read this short commentary, more than 400 babies will have been born too early, another 300 expecting mothers will develop preeclampsia, and 75 unborn third trimester fetuses will have died in utero (stillbirth). Given the lack of meaningful progress in understanding the physiological changes that occur to allow a healthy, full term pregnancy, it is perhaps not surprising that effective therapies against these great obstetrical syndromes that include prematurity, preeclampsia, and stillbirth remain elusive. Meanwhile, pregnancy complications remain the leading cause of infant and childhood mortality under age five. Does it have to be this way? What more can we collectively, as a biomedical community, or individually, as clinicians who care for women and newborn babies at high risk for pregnancy complications, do to protect individuals in these extremely vulnerable developmental windows? The problem of pregnancy complications and neonatal mortality is extraordinarily complex, with multiple unique, but complementary perspectives from scientific, epidemiological and public health viewpoints. Herein, we discuss the epidemiology of pregnancy complications, focusing on how the outcome of prior pregnancy impacts the risk of complication in the next pregnancy — and how the fundamental immunological principle of memory may promote this adaptive response.

First trimester fetal proportion volumetric measurements using a Virtual Reality approach.

ObjectiveTo establish feasibility and reproducibility of fetal proportion volumetric measurements, using three‐dimensional (3D) ultrasound and a Virtual Reality (VR) system.MethodsWithin a population‐based prospective birth cohort, 3D ultrasound datasets of 50 fetuses in the late first trimester were collected by three ultrasonographers in a single research center. V‐scope software was used for volumetric measurements of total fetus, extremities, head‐trunk, head, trunk, thorax, and abdomen. All measurements were performed independently by two researchers. Intraobserver and interobserver reproducibility were analyzed using Bland and Altman methods.ResultsIntraobserver and interobserver analyses of volumetric measurements of total fetus, head‐trunk, head, trunk, thorax and abdomen showed intraclass correlation coefficients above 0.979, coefficients of variation below 7.51% and mean difference below 3.44%. The interobserver limits of agreement were within the ±10% range for volumetric measurements of total fetus, head–trunk, head and trunk. The interobserver limits of agreement for extremities, thorax and abdomen were −26.09% to 4.77%, −14.14% to 10.00% and −14.47% to 8.83%, respectively.ConclusionFirst trimester fetal proportion volumetric measurements using 3D ultrasound and VR are feasible and reproducible, except volumetric measurements of the fetal extremities. These novel volumetric measurements may be used in future research to enable detailed studies on first trimester fetal development and growth.

Estimating cerebral venous oxygenation in human fetuses with ventriculomegaly using quantitative susceptibility mapping

Rationale and objectivesThe goal of this study was to estimate venous blood oxygen saturation (SvO2) in the superior sagittal sinus (SSS) in fetal brains with ventriculomegaly (VM) using quantitative susceptibility mapping (QSM). Materials and methodsA radiofrequency spoiled gradient echo sequence was used to evaluate data on 19 fetuses with VM (gestational age(GA): median = 29.9 weeks (range 23 to 37.3 weeks)) and 20 healthy fetuses (GA: median = 30.9 (range 22.7 to 38.7 weeks)) at 1.5 T. Susceptibility weighted images encompassing the entire fetal brain were acquired within 1 min. An iterative, geometry constraint-based thresholded k-space division algorithm was used for generating QSM data of the fetal brain. The venous oxygen saturation was calculated using the magnetic susceptibility of the SSS obtained from the QSM data. Mixed-model analysis of variance and interobserver variability assessment were used to analyze the results. ResultsThe median SvO2 values in the entire VM cohort as well as for second and third trimester fetuses (with interquartile range) were: 67.8% (63.2%, 73.6%), 73.1% (69.1%, 77.3%) and 63.8% (59.4%, 68.1%), respectively. The corresponding median SvO2 value in the healthy control group was: 65.3% (58.3%, 68.2%), 67.5% (61.7%, 69.2%) and 60.8% (53.6%, 68.2%), respectively. However, the difference of SvO2 between VM and control groups was not significant at the p = 0.05 level (p = 0.076). The SvO2 was found decreasing significantly with GA in the healthy control group (p < 0.05). ConclusionsWe report for the first time the estimation of cerebral SvO2 in human fetuses with VM using QSM. This measure of oxygen saturation might be beneficial in assessing and monitoring the metabolic status of the fetus in various clinical conditions.

Interactions between PDA-associated polymorphisms and genetic ancestry alter ductus arteriosus gene expression

BackgroundDNA polymorphisms in PTGIS and TFAP2B have been identified as risk factors for patent ductus arteriosus (PDA) in a population composed of preterm infants with European genetic ancestry but not in more genetically diverse populations.GoalTo determine if the effects of TFAP2B and PTGIS polymorphisms on ductus arteriosus (DA) gene expression differ based on genetic ancestry.MethodsDA from 273 human second trimester fetuses were genotyped for TFAP2B and PTGIS polymorphisms and for polymorphisms distributing along genetic ancestry lines. RT-PCR was used to measure the RNA expression of 49 candidate genes involved with DA closure.ResultsSeventeen percent of the DA analyzed were of European ancestry. In multivariable regression analyses we found consistent associations between four PDA-related TFAP2B polymorphisms (rs2817399(A), rs987237(G), rs760900(C), and rs2817416(C)) and expression of the following genes: EPAS1, CACNB2, ECE1, KCNA2, ATP2A3, EDNRA, EDNRB, BMP9, and BMP10, and between the PTGIS haplotype rs493694(G)/rs693649(A) and PTGIS and NOS3. These changes only occurred in DA with European ancestry. No consistent positive or negative associations were found among DA samples unless an interaction between the polymorphisms and genetic ancestry was taken into account.ConclusionPTGIS and TFAP2B polymorphisms were associated with consistent changes in DA gene expression when present in fetuses with European ancestry.ImpactDNA polymorphisms in PTGIS and TFAP2B have been identified as risk factors for patent ductus arteriosus (PDA) in a population composed primarily of preterm infants with European genetic ancestry but not in more genetically diverse populations.The same PTGIS and TFAP2B polymorphisms are associated with changes in ductus gene expression when present in ductus from fetuses with European genetic ancestry.No consistent associations with gene expression can be found unless an interaction between the polymorphisms and genetic ancestry is taken into account.

Sylvian fossa sonographic measurements in 18 to 23 weeks fetuses with and without cerebral malformations

Abnormal sulcation of the brain is frequently associated with severe malformations, but the prenatal diagnosis is challenging, especially in early pregnancy. Our study aimed to investigate the value of Sylvian fossa sonographic biometry in the diagnosis of cerebral malformation in the second trimester of gestation. We prospectively established the normal values of the Sylvian fossa depth in a cohort of nonconsecutive patients, with singleton pregnancies and normal fetuses between 18+0 and 23+0 weeks' gestation. For each patient, a coronal view of the fetal brain, with a clear visualization of the anterior complex and the Sylvian fissure, was acquired by 1 sonologist, who also measured the depth of the fossa. Reproducibility for each parameter was assessed by a second sonologist using stored images. We also retrospectively acquired the same measurements in second trimester fetuses with central nervous system anomalies. In 103 fetuses with a normal sonogram, the mean depth of the Sylvian fossa was 3.9±0.8 mm Interobserver reproducibility analysis demonstrated good results. Notably, 11 of 31 fetuses with cerebral malformations had a Sylvian fossa depth of <-2 z-scores, and these were found to have malformations of cortical development, lissencephaly in particular, or microcephaly. Sonographic measurement of the Sylvian fossa during second trimester is feasible and reproducible. A shallow Sylvian fossa is associated with malformations of cortical development, microcephaly, or both.

Water-fat magnetic resonance imaging of adipose tissue compartments in the normal third trimester fetus.

Assessment of fetal adipose tissue gives information about the future metabolic health of an individual, with evidence that the development of this tissue has regional heterogeneity. To assess differences in the proton density fat fraction (PDFF) between fetal adipose tissue compartments in the third trimester using water-fat magnetic resonance imaging (MRI). Water-fat MRI was performed in a 1.5-T scanner. Fetal adipose tissue was segmented into cheeks, thorax, abdomen, upper arms, forearms, thighs and lower legs. PDFF and R2* values were measured in each compartment. Twenty-eight women with singleton pregnancies were imaged between 28 and 38weeks of gestation. At 30weeks' gestation (n=22), the PDFF was statistically different between the compartments (P<0.0001), with the highest PDFF in cheeks, followed by upper arms, thorax, thighs, forearms, lower legs and abdomen. There were no statistical differences in the rate of PDFF change with gestational age between the white adipose tissue compartments (P=0.97). Perirenal brown adipose tissue had a different PDFF and R2* compared to white adipose tissue, while the rate of R2* change did not significantly change with gestational age between white adipose tissue compartments (P=0.96). Fetal adipose tissue accumulates lipids at a similar rate in all white adipose tissue compartments. PDFF variances between the compartments suggest that accumulation begins at different gestational ages, starting with cheeks, followed by extremities, trunk and abdomen. Additionally, MRI was able to detect differences in the PDFF between fetal brown adipose tissue and white adipose tissue.

Double aneuploidy with karyotype 48,XXY,+18 in first trimester fetus - case report

Double aneuploidy with karyotype 48,XXY,+18 in first trimester fetus - case report

Association Between Abnormal Fetal Head Growth and Autism Spectrum Disorder

Despite evidence for the prenatal onset of abnormal head growth in children with autism spectrum disorder (ASD), studies on fetal ultrasound data in ASD are limited and controversial. We conducted a longitudinal matched case-sibling-control study on prenatal ultrasound biometric measures of children with ASD, and 2 control groups: (1) their own typically developed sibling (TDS) and (2) typically developed population (TDP). The cohort comprised 528 children (72.7% male), 174 with ASD, 178 TDS, and 176 TDP. During the second trimester, ASD and TDS fetuses had significantly smaller biparietal diameter (BPD) than TDP fetuses (adjusted odds ratio for the z score of BPD [aORzBPD] = 0.685, 95% CI= 0.527-0.890, and aORzBPD= 0.587, 95% CI= 0.459-0.751, respectively). However, these differences became statistically indistinguishable in the third trimester. Interestingly, head biometric measures varied by sex, with male fetuses having larger heads than female fetuses within and across groups. A linear mixed-effect model assessing the effects of sex and group assignment on fetal longitudinal head growth indicated faster BPD growth in TDS versus both ASD and TDP in male fetuses (β= 0.084 and β= 0.100 respectively; p< .001) but not in female fetuses, suggesting an ASD-sex interaction in head growth during gestation. Finally, fetal head growth showed conflicting correlations with ASD severity in male and female children across different gestation periods, thus further supporting the sex effect on the association between fetal head growth and ASD. Our findings suggest that abnormal fetal head growth is a familial trait of ASD, which is modulated by sex and is associated with the severity of the disorder. Thus, it could serve as an early biomarker for ASD.

Establishment of a Novel Human Fetal Adrenal Culture Model that Supports de Novo and Manipulated Steroidogenesis.

Disorders affecting adrenal steroidogenesis promote an imbalance in the normally tightly controlled secretion of mineralocorticoids, glucocorticoids, and androgens. This may lead to differences/disorders of sex development in the fetus, as seen in virilized girls with congenital adrenal hyperplasia (CAH). Despite the important endocrine function of human fetal adrenals, neither normal nor dysregulated adrenal steroidogenesis is understood in detail. Due to significant differences in adrenal steroidogenesis between human and model species (except higher primates), we aimed to establish a human fetal adrenal model that enables examination of both de novo and manipulated adrenal steroidogenesis. Human adrenal tissue from 54 1st trimester fetuses were cultured ex vivo as intact tissue fragments for 7 or 14 days. Model validation included examination of postculture tissue morphology, viability, apoptosis, and quantification of steroid hormones secreted to the culture media measured by liquid chromatography-tandem mass spectrometry. The culture approach maintained cell viability, preserved cell populations of all fetal adrenal zones, and recapitulated de novo adrenal steroidogenesis based on continued secretion of steroidogenic intermediates, glucocorticoids, and androgens. Adrenocorticotropic hormone and ketoconazole treatment of ex vivo cultured human fetal adrenal tissue resulted in the stimulation of steroidogenesis and inhibition of androgen secretion, respectively, demonstrating a treatment-specific response. Together, these data indicate that ex vivo culture of human fetal adrenal tissue constitutes a novel approach to investigate local effects of pharmaceutical exposures or emerging therapeutic options targeting imbalanced steroidogenesis in adrenal disorders, including CAH.

Tricuspid Valve Dysplasia at Fetal Autopsy

Introduction: Tricuspid valve abnormalities detected in fetal life include Ebstein anomaly and tricuspid valve dysplasia. The differentiation between these 2 entities can sometimes be challenging in the 2nd trimester fetus. We report a case of tricuspid valve dysplasia diagnosed on fetal autopsy. Case Report: A primigravida was diagnosed at 22 weeks’ gestation to have Ebstein anomaly with severe tricuspid regurgitation. There was intra-uterine fetal demise. On fetal autopsy, the tricuspid valve leaflets were not apically displaced and the leaflets were nodular with rolled up edges. This supported a diagnosis of tricuspid valve dysplasia. Conclusion: The difficulties in differentiating Ebstein anomaly from tricuspid valve dysplasia due to inherent limitations in fetal imaging can be resolved by fetal autopsy. Valvular dysplasia will not have apical displacement of the valve leaflets.

VP10.20: Prenatal stomach position in second and third trimester in fetuses with congenital diaphragmatic hernia

The aim of the study is to determine the variability of stomach position (SP) between second and third trimester in fetuses with left-sided congenital diaphragmatic hernia (LCDH). Fetuses with isolated LCDH (2007-2018) were evaluated from 19 weeks' gestational age (GA) onwards. Two ultrasound scans were performed: US1 in the second trimester (18-<24 weeks' GA) and US2 in the third trimester (≥30 weeks' GA). Only fetuses with available data on both US1 and US2 were included. SP was assessed on stored 2D ultrasound data and scored 1-4 (grade 1: abdominal; grade 2: anterior in chest; grade 3: mid to posterior in the chest and grade 4: retrocardiac) in accordance to the grading system proposed by Cordier et al. Primary outcome was the agreement of SP grade between the second and third trimester. 43 fetuses with LCDH were eligible for inclusion. Of these 43 fetuses, 8 fetuses (19%) showed a grade 1, 8 (19%) a grade 2, 26 (60%) a grade 3 and 1 (2%) a grade 4 SP at US1. In 38 (88%) fetuses SP grade did not differ between US1 and US2 with a strong agreement between these two measurements (kappa = 0.893, 0.750-0.976). Five fetuses were graded different (12%) at US2 compared to US1. SP grade of one fetus changed from grade 1 at US1 to grade 2 at US2. One fetus who was classified as a grade 2 at US1 appeared to be a grade 1 at US2. Two fetuses had grade 3 at US1 and grade 2 at US2. One fetus had a grade 3 SP at US1 and grade 4 at US2. No fetuses changed more than one grade between the US1 and US2. SP grade in fetuses with LCDH is consistent in the majority of cases throughout the second and third trimester of pregnancy. This knowledge could help us in studying the value of prenatal SP throughout gestation as a predictor of postnatal outcomes in LCDH patients.

VP04.01: High‐resolution ultrasound in malformed first trimester fetuses with fetoscopic correlation: a single centre case series

VP04.01: High‐resolution ultrasound in malformed first trimester fetuses with fetoscopic correlation: a single centre case series

Conotruncal heart defects and aortic arch anomalies in fetuses with 22q11.2 deletion syndrome

16 second trimester fetuses with 22q11.2 deletion syndrome have been examined at anatomic-pathological investigation. Main cardiovascular diseases were ascending aorta hypoplasia with aortic valve stenosis (n = 6; 37.5%), truncus arteriosus (n = 5; 31.25%), tetralogy of Fallot (n = 3; 18.75%) and double-outlet right ventricle (n = 1; 6.25%). Ventricular septal defect was present in 16 cases. Associated aortic arch anomalies included interrupted aortic arch (n = 9; 56.25%), right aortic arch (n = 6; 37.5%), retroesophageal ring (n = 1; 6.25%) and aberrant right subclavian arteria (n = 5; 31.25%). 5 fetuses had left ventricular outflow tract obstructive lesions with interrupted aortic arch of type B combined with aberrant right subclavian arteria.

Fluoroquinolone exposure in utero did not affect articular cartilage of resulting foals.

Recent studies have shown that fluoroquinolones, specifically, enrofloxacin and its active metabolite (ciprofloxacin), cross the equine placenta without causing gross or histological lesions in the first and third trimester fetuses or resulting foal. However, it is possible that in utero exposure to fluoroquinolones may cause subtle lesions not detectable by standard means; thus, a more in-depth assessment of potential toxicity is warranted. To use quantitative magnetic resonance imaging (qMRI), biomechanical testing, and chondrocyte gene expression to evaluate the limbs of foals exposed to enrofloxacin during the third trimester of pregnancy. In vivo and control terminal experiment. Healthy mares at 280days gestation were assigned into three groups: untreated (n=5), recommended therapeutic (7.5mg/kg enrofloxacin, PO, SID, n=6) or supratherapeutic (15mg/kg, PO, SID, n=6) doses for 14days. Mares carried and delivered to term and nursed their foals for ~30days. Two additional healthy foals born from untreated mares were treated post-natally with enrofloxacin (10mg/kg PO, SID, for 5days). By 30days, foal stifles, hocks, elbows, and shoulders were radiographed, foals were subjected to euthanasia, and foal limbs were analysed by quantitative MRI, structural MRI, biomechanical testing and chondrocyte gene expression. Osteochondral lesions were detected with both radiography and structural MRI in foals from both enrofloxacin-treated and untreated mares. Severe cartilage erosions, synovitis and joint capsular thickening were identified in foals treated with enrofloxacin post-natally. Median cartilage T2 relaxation times differed between joints but did not differ between treatment groups. A small sample size was assessed and there was no long-term follow-up. While further research is needed to address long-term foal outcomes, no differences were seen in advanced imaging, biomechanical testing or gene expression by 30days of age, suggesting that enrofloxacin may be a safe and useful antibiotic for select bacterial infections in pregnant mares.