Choroid plexus cyst, intracardiac echogenic focus, hyperechogenic bowel and hydronephrosis in screening for trisomy 21 at 11 + 0 to 13 + 6 weeks

Second trimester soft markers: still worth to be mentioned?

Despite the widespread use of cell-free DNA in screening for trisomy 21, soft markers continue to be assessed in the second trimester, leading to confusion about how they affect the risk of trisomy 21, especially after an earlier screening test such as cell-free DNA screening. In this review, we provide an overview of commonly used second trimester soft markers, explain how they can be used to calculate the risk for trisomy 21, and discuss what other chromosomal or structural abnormalities might be associated with these markers. We especially focus on pathogenic copy number variants as these, in aggregate, are common and are very difficult to detect using cfDNA or even standard karyotyping.

Congenital Anomalies of the Kidney and Urinary Tract in Down Syndrome: Prevalence, Phenotypes, Genetics and Clinical Management

Down syndrome (DS), the most common survivable autosomal aneuploidy, is associated with a high prevalence of congenital anomalies of the kidney and urinary tract (CAKUT), significantly increasing the risk of chronic kidney disease (CKD). This review examines the diversity of CAKUT phenotypes reported in individuals with DS, focusing on anomalies affecting the kidney, ureter, bladder, and urethra. According to available literature, hydronephrosis is the most common renal anomaly, often secondary to other CAKUT phenotypes, followed by renal hypoplasia and glomerulocystic disease. Furthermore, obstructive uropathies are also frequent but usually lack detailed characterization in the literature. Key features of CAKUT in DS, including reduced kidney size, renal cystic diseases, acquired glomerulopathies, reduced nephron number, and immature glomeruli heighten the risk of CKD. Also, early detection of lower urinary tract dysfunction (LUTD) is critical to prevent progressive upper urinary tract damage and CKD. Despite the prevalence of CAKUT in DS, reported between 0.22% and 21.16%, there is a lack of standardized diagnostic criteria, consistent terminology, and extended follow-up studies. Systematic screening from infancy, including regular renal monitoring via urinalysis and ultrasound, plays a critical role in the timely diagnosis and intervention of CAKUT. To further enhance diagnostic accuracy and develop effective therapeutic strategies, increased awareness and focused research into the genetic factors underlying these anomalies are essential. Moreover, a multidisciplinary approach is indispensable for managing CAKUT and its associated complications, ultimately ensuring better long-term outcomes and an improved quality of life for individuals with DS.

Hyperechogenic fetal bowel: Current evidence-based prenatal diagnosis and management

Echogenic fetal bowel (EB) is a prenatal ultrasound finding (0.2%-1.4% of all pregnancies) defined as bowel of similar or greater echogenicity than surrounding bone. In fact, the ultrasound assessment is strongly subjective with inter-observer variability. The pathophysiology depends on the underlying condition, apparently related with meconium stasis and hypercellularity. It is often an isolated finding, with possible association with other structural anomalies. About the origin, it was observed in fetuses with cystic fibrosis, congenital infections, thalassemia, intraamniotic bleeding, fetal growth restriction. Fetuses with EB are at increased risk of adverse perinatal outcome, such as intrauterine growth restriction, placental dysfunction and perinatal death, highlighting the need for a thorough antenatal management and post-natal follow-up. It seems to be associated with a plenty of conditions, such as a poor fetal outcome, fetal growth restriction and placental dysfunction. Therefore management requires a multidisciplinary approach with different specialties' involvement and the prognosis is influenced by the underlying pathophysiology. In this complex scenario, the present review aims to define the clinical pathway which should be offered to pregnant women in case of finding of fetal EB ultrasound marker, to rule out any suspected pathological cause.

Screening, Management and Delivery in Twin Pregnancy

The following AWMF guideline (DGGG/AGG & DEGUM responsible) deals with the diagnosis, screening and management of twins as well as the timing and mode of birth.Twin pregnancies can be classified as dichorionic diamniotic (DC DA), monochorionic diamniotic (MC DA) and monochorionic monoamniotic (MC MA) which are always monochorionic.Twin pregnancies can be concordant (both twins are affected) or discordant (only one twin is affected) for chromosomal defects, malformations, growth restriction and hemodynamic disorders.Chorionicity is the prognostically most significant parameter. Monochorial twins have significantly higher risks of intrauterine morbidity and mortality compared to dichorial twins.In particular, general aspects of twin pregnancies such as dating, determination of chorionicity and amnionicity, the labeling of twin fetuses and the perinatal switch phenomenon are discussed.Routine monitoring of MC and DC twin pregnancies with ultrasound at 11-13^+ 6 weeks of gestation for chromosomal defects, invasive prenatal diagnosis, first-trimester NT or CRL discrepancies, early diagnosis of fetal anatomical defects, and management of twins with abnormalities, including selective fetocide, is described.Second trimester screening and management for preterm birth, intrauterine selective growth restriction (sFGR), classification of monochorial twins with sFGR, and management of the surviving twin after the death of the co-twin are described.Complications exclusively affecting MC twins include Twin to Twin Transfusion Syndrome (TTTS) with the important topics screening, prognosis, complications of laser therapy, timing of delivery, risks for brain abnormalities and delayed neurological development, Twin Anemia-Polycythemia Sequence (TAPS) and Twin Reversed Arterial Perfusion (TRAP) Sequence. This also includes MC MA twins as well as conjoined twins.Finally, the birth mode and time for DC and MC twin pregnancies are described.The information is summarized in 62 recommendations for action, 4 tables and 8 illustrations with comprehensive background texts.The guideline is an international guideline adaptation (ISUOG, NICE) as well as a systematic literature search and is up-to-date.

Performance of Chromosomal Microarray Analysis for Detection of Copy Number Variations in Fetal Echogenic Bowel

BACKGROUND

Fetal echogenic bowel (FEB) is associated with an increased risk of poor pregnant outcomes; however, karyotyping fails to detect copy number variations (CNVs) in FEB. This study aimed to evaluate the performance of chromosomal microarray analysis (CMA) for detection of FEB.

METHODS

The medical records of 147 pregnant women with FEB recruited during December 2015 to December 2018 were retrospectively reviewed, and prenatal samples were collected for karyotyping and CMA. The detection of chromosomal abnormality was compared between karyotyping and CMA.

RESULTS

Karyotyping identified eight cases with abnormal karyotypes (5.44% prevalence), including four fetuses with pathogenic aneuploidy, three with chromosome polymorphism and one with balanced chromosome translocation. CMA identified 13 abnormal CNVs (8.84% prevalence), including 4 fetuses with pathogenic aneuploidy as detected by karyotyping and 9 additional CNVs with normal karyotypes; however, CMA failed to detect chromosome polymorphism and balanced chromosome translocation. In fetuses with isolated FEB, no cases presented pathogenic findings and CMA detected two cases with variants of uncertain significance (VOUS). In cases presenting FEB along with other ultrasound abnormalities, CMA detected three cases with pathogenic CNVs and four cases with VOUS in addition to four cases with aneuploidy. There was no significant difference in the detection of abnormal CNVs between the fetuses with echogenic bowel alone and along with other ultrasound abnormalities (10% vs 8.67%, P > 0.05). Except 9 fetuses lost to the follow-up, the other 138 fetuses with echogenic bowel were successfully followed up. Pregnancy was terminated in 5 fetuses with chromosomal abnormality, 2 with pathogenic CNVs and 1 with VOUS, and other 16 with normal karyotypes and CMA findings but showing ultrasound abnormalities or multiple malformations.

CONCLUSION

Isolated FEB is associated with a good prognosis, and a satisfactory pregnant outcome is expected for fetuses with echogenic bowel that are negative for chromosomal anomalies and other severe structure abnormalities. CMA shows an important value in the genetic diagnosis of FEB. As a supplement to karyotyping, CMA may improve the accuracy of prenatal diagnosis of fetal intestinal malformations in pregnant women with FEB.

Isolated echogenic intracardiac foci and the role of cell-free fetal DNA: A cost-effectiveness analysis

OBJECTIVES

Cell-free fetal DNA (cfDNA) has been increasingly incorporated into prenatal aneuploidy screening paradigms given its relatively high sensitivity for Down syndrome (DS). This is often the case when fetal ultrasonographic soft markers are present, such as the relatively common echogenic intracardiac focus (EIF). We sought to evaluate the cost-effectiveness of a screening strategy that included cfDNA screening when an isolated EIF is identified in a low-risk population with prior aneuploidy screening.

METHODS

A decision-analytic model was constructed using TreeAge software with probabilities derived from the literature. Our model compared cfDNA screening following isolated EIF detection in women less than 35 years with prior reassuring first trimester screen compared to a strategy of no further aneuploidy screening. Strategies were compared to generate an incremental cost-effectiveness ratio with a threshold of $100 000/quality-adjusted life year (QALY) and applied to a theoretical cohort.

RESULTS

The cfDNA strategy resulted in 21 fewer DS births and 52 additional QALYs, however, increased costs by $51.3 million. This yielded an incremental cost-effectiveness ratio of $986 503; therefore, it was not a cost-effective strategy.

CONCLUSION

In a low-risk population with prior reassuring aneuploidy screening, it is not cost effective to offer cfDNA after identification of an isolated EIF.

Segmental aneuploidies in fetuses with isolated echogenic intracardiac focus among women younger than 35 years

Studies on the occurrence of segmental aneuploidoidy in fetuses with isolated echogenic intracardiac focus (EIF) are scarce. The aim of this study was to analyze whether there is an association between abnormal segmental aneuploidies and isolated EIF. This was a prospective case-control study. The study participants in the case group were fetuses that were diagnosed with isolated EIF. Samples without fetal ultrasound abnormalities but received prenatal diagnosis for other reasons (serological screening high-risk, voluntary request) were set as controls. All pregnant women were younger than 35 years old at the expected date of childbirth. Copy number variation sequencing (CNV-seq) was performed for all samples. The case group and control group successfully underwent CNV-seq analysis and exhibited 1,099 and 5,616 amniotic fluid samples, respectively. The detection rates of abnormal segmental aneuploidies in the case group and control group were 0.6% (7/1,099) and 1.1% (64/5,616), respectively; no statistically significant difference was found between the two groups (x2 = 2.220, P = 0.136). Isolated EIF did not increase the risk of fetal segmental aneuploidies.

Chromosomal microarray analysis for the detection of chromosome abnormalities in fetuses with echogenic intracardiac focus in women without high-risk factors

To investigate the association between pathogenic copy number variants (p-CNVs) and abnormal karyotypes detected by chromosomal microarray analysis (CMA) and echogenic intracardiac focus (EIF).This was a retrospective study of fetuses with EIF with CMA data at the Prenatal Diagnosis Center of the West China Second University Hospital of Sichuan University between September 2014 and May 2017. Fetuses were assigned to the isolated EIF and non-isolated EIF groups according to the presence of other ultrasound abnormalities.Among 244 pregnant women, there were 143 cases of isolated EIF and 101 of non-isolated EIF. CMA revealed chromosome abnormality (n = 9 (3.7%): trisomy 21, n = 4; sexual trisomy, n = 2; and p-CNV, n = 3), variants of unknown significance (VOUS, n = 19), and benign CNV (b-CNV, n = 216). Among the fetuses with isolated EIF, 5 had chromosomal abnormalities (3.5%). Among the fetuses with non-isolated EIF, four had chromosomal abnormalities (4.0%). All fetuses with trisomy 21 were in the non-isolated group. The frequency of labor induction was 66.7% (6/9) among the fetuses with chromosome abnormality and 21.1% (4/19) among those with VOUS. Among those with chromosomal abnormalities, one (11.1%) had congenital heart disease.In pregnant women without high-risk factors for chromosomal abnormalities, ultrasound abnormalities, including EIF, could be an indication for CMA. Ultrasound abnormalities (including EIF) and chromosome abnormality could indicate a high risk of CHD. The presence of EIF and at least another ultrasound abnormality could indicate a high risk of trisomy 21.

Outcome after prenatal diagnosis of fetal urinary tract abnormalities: A tertiary center experience

Objective:

With the widespread use of ultrasonography for fetal screening, the detection and management of congenital urinary tract abnormalities has become crucial. In this study, we aimed to describe the clinical approaches in patients with prenatally detected urinary tract abnormalities.

Material and Methods:

This study is a retrospective, single-center study performed at a perinatology unit of a university hospital, between 2010 and 2016. The outcomes of 124 patients who were prenatally diagnosed as having urinary tract abnormalities are reported. Variables included in the analysis were fetal sex, birth week and weight, persistency, and necessity surgery after birth for renal pelvic dilatation. Low-risk renal pelvic dilatation was determined as an anterior-posterior (AP) diameter of 4-7 mm at 16-28 weeks, 7-10 mm after 28 weeks, whereas high-risk dilatation was defined as AP measurements of ≥7 mm at 16-28 weeks, ≥10 mm after 28 weeks, respectively.

Results:

The majority of patients consisted of male fetuses with bilateral pelviectasis (62.9%, 20.2%, respectively). The mean age was 28.8±6.4 years. The mean gestational age at birth was 34.2±7.8 weeks. The mean birth weight was 2593±1253.3 g. The need for surgery was greater in high-risk patients than in low-risk patients (58.3% vs. 8.7%) (p<0.002).

Conclusion:

Patients with high-risk antenatal renal pelvic dilatation require surgical treatment after delivery. Close prenatal and postnatal follow-up is mandatory in specialized centers. Perinatologists, neonatologists, pediatricians and pediatric nephrologists, and radiologists should treat these children with a multidisciplinary approach.

Long-Term Outcome of Fetuses with Soft Marker and Without Genetic or Structural Abnormality

Purpose

To determine long-term outcome of infants with isolated or multiple soft markers but no structural or chromosomal abnormalities.

Methods

A retrospective study of 78 pregnant women who were referred for amniocentesis and found to have soft markers including echogenic intracardiac focus/foci (EIF), echogenic bowel (EB), unilateral or bilateral choroid plexus cysts, (UCPCs or BCPCs) mild pyelectasis and single umbilical artery but no structural anomalies and outcomes of the liveborns with a 4- to 9-year follow-up was conducted.

Results

Among 28 fetuses with EIF, allergic asthma and epilepsy were diagnosed in two liveborns. We followed up nine pregnancies with EB, epilepsy was present in one case. Allergic asthma was detected in both UCPCs and BCPCs, whereas epilepsy and attention-deficit/hyperactivity disorder (ADHD) were diagnosed in two liveborns with BCPCs. Twelve liveborns with multiple soft markers were evaluated; no pathology was detected in most of them except one case of allergic asthma, one case of hearing impairment and one case of ADHD.

Conclusions

This study shows longer-term favorable outcomes of the liveborns with isolated or multiple soft markers without any aneuploidy and may provide insight into this debated point.

The recurrence of sonographic 'soft markers': ominous sign or 'just' genetics?

OBJECTIVES

'Soft markers' (SMs) are nonspecific findings that might convey a higher risk for Down syndrome. We sought to determine the recurrence rate of the most common SM in subsequent pregnancies.

METHODS

This is a retrospective study of all women who underwent early or late fetal sonographic anatomical screening in our ultrasound unit. The examined SMs were pyelectasis, thickened nuchal fold (TNF) and echogenic intracardiac foci (EIF). Data on recurrence and pregnancy outcome were retrieved retrospectively.

RESULTS

The database included 20 672 singleton pregnancies; SMs were detected in 2347 (11.1%) of the fetuses and were isolated in 1739 (74%). Rates of solitary findings in the pregnancies were 6.5% (1360/20 672) EIF, 3% (624/18 850) TNF and 1.7% (363/20 672) pyelectasis. The recurrence rate of EIF, TNF and pyelectasis in subsequent consecutive pregnancies was 21%, 27% and 16%, respectively. Overall, 62 cases of Down syndrome were diagnosed in (1 : 333 pregnancies). No cases were diagnosed in patients with recurrent SMs.

CONCLUSION

The high recurrence rate of solitary SM implies for genetic predisposition. These results might improve our counseling for pregnant women affected by the reappearance of solitary SM. Further studies are needed to assess the likelihood ratio for SM if recurrence occurs. © 2017 John Wiley & Sons, Ltd.

Fetal Kidneys Ultrasound Appearance in the First Trimester - Clinical Significance and Limits of Counseling

OBJECTIVE

The objective of this study was to determine the visualizing rate of fetal kidneys at various gestational ages in late first trimester (FT) and to establish the clinical significance of their two-dimensional ultrasound (2DUS) appearance in the FT.

METHODS

In a prospective cross-sectional study, 1456 women from an unselected population underwent a detailed assessment of fetal anatomy at 11+0 -13+4 weeks of gestation with the use of transabdominal sonography. Information on the ultrasound findings, antenatal course and perinatal outcome was obtained in 1331 cases.

RESULTS

44 cases in which a congenital kidney disease was detected by ultrasound in the prenatal period were identified. The renal pathology was suspected in the FT in 8 cases, and confirmed by a standard test (postmortem autopsy or second-trimester scan) in 4 cases. The standard detailed second-trimester scan at 18-22 weeks diagnosed another 23 cases but refuted suspicion in 4 FT positive cases. The third trimester added another 17, all confirmed by the postpartum scan. For FT presence or absence of congenital renal anomalies, sensitivity, specificity, +LRs and -LRs of 2DUS were 9.09%, 99.69%, 29.25, and 0.91.

CONCLUSION

FT prenatal kidneys' visualization is critically dependent on the gestational age. FT diagnosis holds uncertainty. An early diagnosis carries a risk of providing a false-positive or a false-negative result, because the differentiation of the renal system is delayed or the diagnosis is not amenable yet to prenatal ultrasound. No FT findings can exclude the mid-trimester follow-up ultrasound scan. Second and third trimester scan are relevant for congenital kidney diseases.

Fetal imaging: executive summary of a joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Institute of Ultrasound in Medicine, American College of Obstetricians and Gynecologists, American College of Radiology, Society for Pediatric Radiology, and Society of Radiologists in Ultrasound Fetal Imaging workshop

Given that practice variation exists in the frequency and performance of ultrasound and magnetic resonance imaging (MRI) in pregnancy, the Eunice Kennedy Shriver National Institute of Child Health and Human Development hosted a workshop to address indications for ultrasound and MRI in pregnancy, to discuss when and how often these studies should be performed, to consider recommendations for optimizing yield and cost effectiveness, and to identify research opportunities. This article is the executive summary of the workshop.

The utilization of circulating cell-free fetal DNA testing and decrease in invasive diagnostic procedures: an institutional experience

OBJECTIVE

To characterize the patient population utilizing circulating cell-free fetal DNA (ccffDNA) testing at a large academic center and evaluate trends in the performance of invasive diagnostic procedures.

STUDY DESIGN

A retrospective cohort study of all patients who underwent cell-free DNA testing from May to December 2012 was performed.

RESULT

During the study period, 206 patients had cell-free DNA testing. Of those, 75% (155/206) were of ages ⩾ 35 years. Of those undergoing ccffDNA testing, 41% had positive aneuploidy screening and 38% had abnormal ultrasound findings. Only 7% of the patients with negative ccffDNA testing opted for an invasive diagnostic procedure compared with 60% with positive testing (P<0.01). The rate of invasive procedures decreased from 5.9% of all visits to the center during a similar 8-month period in 2010 to 4.1% of all visits during the study period (P<0.01).

CONCLUSION

Our data suggest that ccffDNA testing leads to reduced uptake of invasive procedures.

Fetal imaging: Executive summary of a Joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Institute of Ultrasound in Medicine, American College of Obstetricians and Gynecologists, American College of Radiology, Society for Pediatric Radiology, and Society of Radiologists in Ultrasound Fetal Imaging Workshop

Given that practice variation exists in the frequency and performance of ultrasound and magnetic resonance imaging in pregnancy, the Eunice Kennedy Shriver National Institute of Child Health and Human Development hosted a workshop to address indications for ultrasound and magnetic resonance imaging in pregnancy, to discuss when and how often these studies should be performed, to consider recommendations for optimizing yield and cost-effectiveness and to identify research opportunities. This article is the executive summary of the workshop.

Fetal imaging: executive summary of a joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Institute of Ultrasound in Medicine, American College of Obstetricians and Gynecologists, American College of Radiology, Society for Pediatric Radiology, and Society of Radiologists in Ultrasound Fetal Imaging Workshop

Given that practice variation exists in the frequency and performance of ultrasound and magnetic resonance imaging (MRI) in pregnancy, the Eunice Kennedy Shriver National Institute of Child Health and Human Development hosted a workshop to address indications for ultrasound and MRI in pregnancy, to discuss when and how often these studies should be performed, to consider recommendations for optimizing yield and cost effectiveness, and to identify research opportunities. This article is the executive summary of the workshop.

Follow-up of sonographically detected soft markers for fetal aneuploidy

Sonographic soft markers of fetal Down syndrome were first reported in the 1980s. With improvements in aneuploidy screening, detection rates of 90% and higher are possible, and such screening is offered to women of all ages. The utility of sonographic detection and reporting of soft markers, particularly to women at low risk of fetal aneuploidy, is controversial. Some soft markers have no additional significance beyond an association with aneuploidy, while some potentially indicate other pathology, and therefore require sonographic follow-up or other evaluation. The definitions of soft markers vary among reported series, and any practice using such markers to adjust the risk of aneuploidy should carefully determine the most appropriate definitions as well as likelihood ratios and how to apply these in practice.

Early fetal anatomical sonography

Over the past decade, prenatal screening and diagnosis has moved from the second into the first trimester, with aneuploidy screening becoming both feasible and effective. With vast improvements in ultrasound technology, sonologists can now image the fetus in greater detail at all gestational ages. In the hands of experienced sonographers, anatomic surveys between 11 and 14 weeks can be carried out with good visualisation rates of many structures. It is important to be familiar with the normal development of the embryo and fetus, and to be aware of the major anatomical landmarks whose absence or presence may be deemed normal or abnormal depending on the gestational age. Some structural abnormalities will nearly always be detected, some will never be and some are potentially detectable depending on a number of factors.

Pränatale Detektion fetaler chromosomaler Aberrationen im 1. und 2. Trimenon

Die modernen nichtinvasiven Verfahren der pränatalen Medizin, vertreten vor allem durch das Ersttrimesterscreening, ermöglichen eine frühe Risikoeinschätzung bzgl. der häufigsten Aneuploidien. Durch die flächendeckende Anwendung dieser Methode mit derzeit weit über 4000 zertifizierten Gynäkologen bundesweit stellt dies heute einen weit verbreiteten Standard dar. Die klassische „genetische“ Sonographie, d. h. die Detektierung von Softmarkern als Hinweiszeichen für eine Aneuploidie im 2. Trimenon, hat an Bedeutung verloren. Allerdings ist der Fehlbildungsultraschall im 2. Trimenon nach wie vor von sehr großer Bedeutung und stellt den „Goldstandard“ für die Entdeckung angeborener Fehlbildungen dar. Der Pränatalmediziner muss in der Lage sein, während dieser Untersuchung Softmarker zu erkennen, um ggf. eine Reevalution des mütterlichen Risikos bzgl. Aneuploidien vorzunehmen.

Fetal genitourinary anomalies--a pictorial review with postnatal correlation

An accurate diagnosis of fetal genitourinary abnormality is essential because some genitourinary abnormalities are associated with pulmonary hypoplasia, which ultimately affects the neonatal outcome. Adrenal masses are rare; however, presence of any lesion located at the superior pole of the kidney should raise the possibility of an adrenal mass. Fetal genital anomalies are rare as well and some of the most difficult to diagnose. A combination and pattern of findings allows for specific diagnosis of renal tract abnormalities. This article reviews the imaging appearance of fetal genitourinary abnormalities with perinatal imaging correlation where available.

Role of first-trimester sonography in the diagnosis of aneuploidy and structural fetal anomalies

OBJECTIVE

We sought to determine the sensitivity of the first-trimester scan in the early diagnosis of aneuploidy and structural fetal anomalies in an unselected low-risk population.

METHODS

This was a retrospective chart review of all patients having first-trimester scans between 2002 and 2009. At our center, a survey of fetal anatomy is performed at the time of nuchal translucency assessment at 11 weeks to 13 weeks 6 days. A second-trimester scan is done at 20 to 23 weeks and a third-trimester scan at 32 to 35 weeks. Isolated sonographic findings of choroid plexus cysts and echogenic intracardiac foci were excluded. Lethal anomalies and those requiring immediate surgical intervention at birth were considered major structural anomalies. All scans were performed by a single sonologist certified by the Fetal Medicine Foundation. All neonates were examined at birth by a pediatrician.

RESULTS

Our study included 1370 fetuses. Six cases of aneuploidy (0.4%) were detected. The first-trimester scan detected 5 of 6 cases of aneuploidy (83%), confirmed by karyotype. There were 36 cases of structural fetal anomalies (2.6%); 20 (1.5%) were major anomalies. The first-trimester scan detected 16 of 36 (44%); 20 (56%) were identified by second- or third-trimester scans. The first-trimester scan detection rate for major structural anomalies was 14 of 20 (70%). The 5 that were missed by the first-trimester scan were detected by a second-trimester scan.

CONCLUSIONS

Our study emphasizes the importance of the first-trimester scan in the early detection of aneuploidy and structural fetal anomalies. In this small unselected low-risk population, the first-trimester scan detected 83% of aneuploidies and 70% of major structural anomalies. Our results are comparable to previously published studies from other centers and further exemplify the invaluable role of the first-trimester scan in the early detection of aneuploidy and structural anomalies in an unselected low-risk population.

First-trimester genetic counseling: perspectives and considerations

As first trimester screening has assumed an increasingly dominant role in the obstetric care of prospective parents, the need for genetic counseling has also increased. There are several challenges related to first trimester screening; foremost among them is the need to distinguish between screening and diagnosis. Additional challenges include the need to discuss not only Down syndrome but cardiac defects, developmental/genetic syndromes, adverse pregnancy outcomes, and preeclampsia. In the future, counseling will involve specific risk assessment for a broad range of chromosome abnormalities. This article provides a framework for providing genetic counseling to prospective parents undergoing first trimester screening. However, the counseling session has to be individualized based on the counselor's approach and unique issues and concerns related to the pregnancy.

The Society for Fetal Urology consensus statement on the evaluation and management of antenatal hydronephrosis

The evaluation and management of fetuses/children with antenatal hydronephrosis (ANH) poses a significant dilemma for the practitioner. Which patients require evaluation, intervention or observation? Though the literature is quite extensive, it is plagued with bias and conflicting data, creating much confusion as to the optimal care of patients with ANH. In this article, we summarized the literature and proposed recommendations for the evaluation and management of ANH.

First Trimester Ultrasound Screening: An Update

For many years, the main use of ultrasound in the first trimester of pregnancy was to confirm viability and to establish gestational age. Indeed, the crown-rump length measurement in the first trimester remains the most accurate method to estimate the gestational age even today. However, improvements in ultrasound equipment and improvement in our understanding of normal and abnormal fetal development allows us now to perform a much more complete first trimester fetal evaluation. This pertains not only to the diagnosis of fetal anomalies but also to screening for fetal defects. The combination of the nuchal translucency measurement and maternal serum biochemistries (free β-hCG and PAPP-A) has been shown to be an extremely efficient way to screen for fetal aneuploidy. The addition of other first trimester markers such as the nasal bone evaluation, frontomaxillary facial angle measurement, and Doppler evaluation of blood flow across the tricuspid valve and through the ductus venosus improves the screening performance even further by increasing the detection rates and decreasing the false positive rates. Several of the first trimester markers also are useful in screening for cardiac defects. Furthermore, significant nuchal translucency thickening has been associated with a variety of genetic and nongenetic syndromes. A recently described first trimester marker called the intracerebral translucency appears to hold great promise in screening for open spine defects. Finally, it appears that a first trimester evaluation (uterine artery Doppler and the measurement of certain biochemical markers in the maternal serum) significantly improves the assessment of the risk of preeclampsia.