The American Association for Thoracic Surgery (AATS) 2023 Expert Consensus Document: Recommendation for the care of children with trisomy 13 or trisomy 18 and a congenital heart defect.

OBJECTIVES: Recommendations for surgical repair of a congenital heart defect in children with trisomy 13 or trisomy 18 remain controversial, are subject to biases, and are largely unsupported with limited empirical data. This has created significant distrust and uncertainty among parents and could potentially lead to suboptimal care for patients. A working group, representing several clinical specialties involved with the care of these children, developed recommendations to assist in the decision-making process for congenital heart defect care in this population. The goal of these recommendations is to provide families and their health care teams with a framework for clinical decision making based on the literature and expert opinions. METHODS: This project was performed under the auspices of the AATS Congenital Heart Surgery Evidence-Based Medicine Taskforce. A Patient/Population, Intervention, Comparison/Control, Outcome process was used to generate preliminary statements and recommendations to address various aspects related to cardiac surgery in children with trisomy 13 or trisomy 18. Delphi methodology was then used iteratively to generate consensus among the group using a structured communication process. RESULTS: Nine recommendations were developed from a set of initial statements that arose from the Patient/Population, Intervention, Comparison/Control, Outcome process methodology following the groups' review of more than 500 articles. These recommendations were adjudicated by this group of experts using a modified Delphi process in a reproducible fashion and make up the current publication. The Class (strength) of recommendations was usually Class IIa (moderate benefit), and the overall level (quality) of evidence was level C-limited data. CONCLUSIONS: This is the first set of recommendations collated by an expert multidisciplinary group to address specific issues around indications for surgical intervention in children with trisomy 13 or trisomy 18 with congenital heart defect. Based on our analysis of recent data, we recommend that decisions should not be based solely on the presence of trisomy but, instead, should be made on a case-by-case basis, considering both the severity of the baby's heart disease as well as the presence of other anomalies. These recommendations offer a framework to assist parents and clinicians in surgical decision making for children who have trisomy 13 or trisomy 18 with congenital heart defect.

Aplasia Cutis Congenita of the Scalp with Bone Defect and Exposed Sagittal Sinus in Trisomy 13 Newborn - a Case Report.

Background: Aplasia cutis congenita is a heterogeneous disorders group with a rare reported incident of 0.5 to 1 in 10,000 births. ACC can be associated with physical defects or syndrome that may help in diagnosis, prognosis and further evaluation of the patient. Trisomy 13 is one of the most common fetal life limiting diagnosis which is associated with ACC of membranous type scalp. Objective: In this article, we report cases of aplasia cutis congenita of the scalp with dura and bone defect and exposed sagittal sinus in newborn diagnosed to have trisomy 13. It emphasizes the importance of ACC associated syndrome which is having high mortality prior to surgical intervention. Case presentation: The patient was born at 35 weeks of gestation. Her physical examination revealed a newborn girl with dysmorphic facial features including widely separated eyes, downward slanting of the palpebral fissure, microphthalmia, retrognathia, and low seat ears. She had area of loss of scalp skin and skull bone with seen brain tissue and sagittal sinus were exposed that was measure 6 by 5 cm in size. Additionally, she had a clenched fist and overlapping fingers and rocker bottom feet. Laboratory investigations include basic labs and the TORCH screen was negative. On the 9th day of life, a chromosomal analysis showed a female karyotype with three copies of chromosome number 13 in all 20 metaphase cells counts. Conclusion: The patient was managed conservatively. However, a multidisciplinary team agreed on do not resuscitate with no further surgical intervention as survival rate of trisomy 13 is poor.

The common trisomy syndromes, their cardiac implications, and ethical considerations in care.

PURPOSE OF REVIEW: To review the incidence of congenital heart disease in the trisomies, highlight the history of cardiac surgery in trisomy 21 comparing it to the increase in cardiac surgery in trisomies 13 and 18, discuss ethical issues specific to trisomies 13 and 18, and suggest a pathway of shared decision-making in the management of congenital heart disease in trisomy 13 and 18, specifically congenital heart surgery. RECENT FINDINGS: Congenital heart disease is prevalent in the trisomies and the management of these defects, especially surgical intervention, has changed. In the late 20th century, survival after cardiac surgery in trisomy 21 vastly improved, significantly decreasing morbidity and mortality secondary to pulmonary hypertension. Similarly, procedures and surgeries have been performed with increasing frequency in trisomy 13 and 18 patients and concomitantly, survival in this patient population is increasing. Yet across the United States, the willingness to perform cardiac surgery in trisomy 13 and 18 is variable, and there is ethical controversy about the correct action to take. To address this concern, a shared decision-making approach with an informed parent(s) is advised. SUMMARY: As the care and management of congenital heart disease changed in trisomy 21, so too it has with trisomy 13 and 18. Physicians and parents should develop goal-directed treatment plans balancing the risk versus benefit and consider cardiac surgical repair if feasible and beneficial.

Low-level mosaic trisomy 13 at amniocentesis in a pregnancy associated with a positive NIPT result suspicious of trisomy 13, a CVS result of mosaic trisomy 13, cytogenetic discrepancy in various tissues and a favorable fetal outcome.

OBJECTIVE: We present low-level mosaic trisomy 13 at amniocentesis in a pregnancy associated with a positive non-invasive prenatal testing (NIPT) result suspicious of trisomy 13, a chorionic villus sampling (CVS) result of mosaic trisomy 13, cytogenetic discrepancy in various tissues and a favorable fetal outcome. CASE REPORT: A 29-year-old, gravida 2, para 1, woman underwent amniocentesis at 20 weeks of gestation because of a positive NIPT result (Z-score = 20.9, positive ≥3) suspicious of trisomy 13 at 11 weeks of gestation and a CVS result of mosaic trisomy 13 at 14 weeks of gestation. At 14 weeks of gestation, CVS revealed the multiplex ligation-dependent probe amplification (MLPA) result of rea X,Y (P095) × 1, 13 (P095) × 3, 18,21 (P095) × 2/X,Y (P095) × 1, 13,18,21 (P095) × 2 and a karyotype of 48,XY,+13,+mar [9]/47,XY,+mar[16]. She was referred to the hospital for genetic counseling at 15 weeks of gestation, and cytogenetic analysis of parental blood revealed 47,XY,+mar in the father and 46, XX in the mother. Fluorescence in situ hybridization (FISH) analysis on the paternal blood showed that the extra dicentric marker was derived from chromosome 15 without the locus SNRPN (15q11.2), and the result was 47,XY,+mar.ish dic(15) (D15Z1++, SNRPN-, PML-)[20]. Amniocentesis at 20 weeks of gestation revealed a karyotype of 47,XY,+mar pat (20/20). Simultaneous interphase FISH analysis on uncultured amniocytes revealed 32% (32/100 cells) mosaicism for trisomy 13. Quantitative fluorescence polymerase chain reaction (QF-PCR) analysis using the DNA extracted from the parental bloods and uncultured amniocytes excluded uniparental disomy (UPD) 13. Prenatal ultrasound findings were normal. The woman was advised to continue the pregnancy, and a phenotypically normal 2708-g male baby was delivered at 38 weeks of gestation, The cord blood, umbilical cord and placenta had the karyotypes of 47,XY,+mar pat and did not have UPD 13. When follow-up at age two months, the neonate was phenotypically normal. FISH analysis on buccal mucosal cells detected 5.3% (5/95 cells) mosaicism for trisomy 13, compared with 0% in the normal control. CONCLUSION: Low-level mosaic trisomy 13 at amniocentesis can be associated with a positive NIPT result suspicious of trisomy 13, a CVS result of mosaic trisomy 13, cytogenetic discrepancy in various tissues and a favorable fetal outcome.

Otolaryngologic Manifestations of Trisomy 13 and Trisomy 18 in Pediatric Patients.

OBJECTIVE: The survival rate of patients with trisomy 13 and trisomy 18 has increased dramatically over the past two decades. We sought to comprehensively describe the otolaryngologic clinical characteristics and procedures required for these patients at our institution. METHODS: We performed algorithmic identification of patients with a diagnosis of trisomy 13 and trisomy 18 for whom the otolaryngology service provided inpatient or outpatient care at our institution between the dates of February 1997 and March 2021. RESULTS: Of the 47 patients studied, 18 patients had a diagnosis of trisomy 13, and 29 had a diagnosis of trisomy 18. Complete trisomy was present in 44% (8/18) of trisomy 13 patients and 55% (16/29) of trisomy 18 patients. 81% of patients were living at the time of the study. About 94% (44/47) of patients required consultation with another specialty in addition to Otolaryngology. Overall, the most common diagnoses among this cohort were gastroesophageal reflux disease (47%), dysphagia (40%), otitis media (38%), and obstructive sleep apnea (34%). Nearly three-quarters (74%) of patients studied required an otolaryngologic procedure. The most common surgical procedure was tonsillectomy and/or adenoidectomy. Patients with trisomy 18 were significantly more likely to have external auditory canal stenosis and obstructive sleep apnea whereas patients with trisomy 13 were more likely to have cleft lip and palate. CONCLUSIONS: Patients with a diagnosis of trisomy 13 or 18 often require multidisciplinary management and the range of required care spans the breadth of otolaryngology. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:1501-1506, 2023.

Improving survival in patients with trisomy 18.

The effects of medical and surgical interventions on the survival of patients with trisomy 18 have been reported, leading to changes in perinatal management and decision-making. However, few studies have fully reported the recent changes in survival and treatment of trisomy 18. We examined how treatment and survival of patients with trisomy 18 have changed over a decade in a Japanese pediatric tertiary referral center. This retrospective cohort study included patients with trisomy 18 who were admitted within the first 7 days of life at the Hyogo Prefectural Kobe Children's Hospital between 2008 and 2017. The patients were divided into early period (EP) and late period (LP) groups based on the birth year of 2008-2012 and 2013-2017, respectively. Changes in treatment and survival rates were compared between the two groups. A total of 56 patients were studied (29 in the EP group and 27 in the LP group). One-year survival rates were 34.5% and 59.3% in the EP and LP groups, respectively. The survival to discharge rate significantly increased from 27.6% in the EP group to 81.5% in the LP group (p < 0.001). The proportion of patients receiving surgery, especially for congenital heart defects, significantly increased from 59% in the EP group to 96% in the LP group (p = 0.001). In our single-center study, survival and survival to discharge were significantly improved in patients with trisomy 18, probably because of increased rate of surgical interventions. These findings may facilitate better decision-making by patients' families and healthcare providers.

Interdisciplinary care of children with trisomy 13 and 18.

Children with trisomy 13 and 18 (previously deemed "incompatible with life") are living longer, warranting a comprehensive overview of their unique comorbidities and complex care needs. This Review Article provides a summation of the recent literature, informed by the study team's Interdisciplinary Trisomy Translational Program consisting of representatives from: cardiology, cardiothoracic surgery, neonatology, otolaryngology, intensive care, neurology, social work, chaplaincy, nursing, and palliative care. Medical interventions are discussed in the context of decisional-paradigms and whole-family considerations. The communication format, educational endeavors, and lessons learned from the study team's interdisciplinary care processes are shared with recognition of the potential for replication and implementation in other care settings.

Increased prenatal detection of 22q11.2 deletion and 22q11.2 duplication after introduction of nationwide prenatal screening for trisomy 21, trisomy 13, and trisomy 18.

OBJECTIVE: To evaluate time of diagnosis of 22q11.2 deletion and 22q11.2 duplication as well as trisomies 21, 13, and 18 before and after introduction of a prenatal screening program including combined first-trimester screening (cFTS) for the trisomies in Denmark in 2004. METHOD: Cross-sectional, population-based register study employing The Danish Cytogenetic Central Register. Proportions of cases diagnosed 1998-2004 and 2005-2017 were compared before 14+0 and 22+0 weeks and birth (prenatal cases) or up to 1 or 10 years of age (postnatal cases). RESULTS: In total, 4562 cases were included. From 1998-2004 to 2005-2017, the proportion of 22q11.2 deletion cases identified prenatally increased from 4.3% (95% CI: 0.9-12.0%) to 27.3% (21.2-34.0%), while for 22q11.2 duplication an increase from 0/6 to 26/87 (prenatal cases/all cases) was observed. Similarly, proportions of trisomies 21, 13, and 18 detected before birth increased. A greater proportion of the studied conditions was identified earlier in pregnancy, but not generally earlier in the postnatal course. CONCLUSION: Proportions of 22q11.2 deletion and 22q11.2 duplication identified prenatally increased after introduction of a prenatal screening program not aimed specifically to identify these conditions,. A greater proportion of all cases were detected earlier in pregnancy, but not earlier postnatally, following introduction of screening.

[Genetic study of a trisomy 13 fetus with a false-negative karyotype by chorionic villi analysis].

OBJECTIVE: To explore the mechanism of a false-negative result from karyotyping of chorionic villi cells for a trisomy 13 fetus featuring multiple malformations. METHODS: For a fetus with multiple malformations by ultrasonography and a 46,XY karyotype by chorionic villi analysis, amniocytes were further analyzed with quantitative fluorescence PCR (QF-PCR), G-banded karyotyping and chromosomal microarray analysis (CMA). Meanwhile, non-invasive prenatal testing (NIPT) was conducted on peripheral blood sample from the pregnant woman to determine the chromosomal composition of cytotrophoblast. After induction of labor, common aneuploidies in placenta and fetal tissue were also analyzed by QF-PCR. RESULTS: QF-PCR, chromosomal karyotyping and CMA analysis of the amniocytes all suggested complete trisomy 13 (47,XY,+13) in the fetus. NIPT also suggested existence of fetal trisomy 13. QF-PCR analysis of the placenta and fetal tissues revealed that cells derived from the maternal surface and right side of fetal surface harbored mosaic trisomy 13, while those derived from other sites of fetal surface of the placenta, umbilical cord, amniotic membrane and fetal muscle tissue harbored trisomy 13. CONCLUSION: Karyotyping of long-term cultured chorionic villus sample may give rise to false negative results due to placental mosaicism. To ensure accurate prenatal diagnosis, discordance between karyotyping of chorionic villi cells, fetal ultrasound and NIPT result should be verified by amniocentesis or cordocentesis and application of multiple cytogenetic and molecular techniques.

Trisomía 9, trisomía 13 y trisomía 18: resultados del análisis citogenético prenatal, Hospital Clínico Universidad de Chile, años 2000-2017 / Trisomy 9, trisomy 13 and trisomy 18: results of the prenatal cytogenical analysis, Hospital Clínico Universidad de Chile, years 2000-2017

INTRODUCCIÓN: En Chile, la norma técnica de la Ley N° 21.030 de 2017 considera tres aneuploidías como letales; las trisomías 9, 13 y 18, cuyo diagnóstico se confirma con un cariograma. No existe a la fecha registro nacional de frecuencia prenatal de estas patologías. OBJETIVO: Determinar la frecuencia de trisomías 9, 13 y 18 en los estudios citogenéticos prenatales en muestras de células obtenidas con amniocentesis y cordocentesis, procesados en el Laboratorio de Citogenética del Hospital Clínico Universidad de Chile. MATERIALES Y MÉTODOS: Estudio descriptivo y retrospectivo de los resultados de cariograma de líquido amniótico (LA) y sangre fetal (SF), procesados desde enero de 2000 a diciembre de 2017. RESULTADOS: Se incluyeron 2.305 muestras (402 de SF y 1.903 de LA), de ellas 442 (19%) fueron trisomías letales (TL), dentro de ellas fueron TL libres 416 (95%), TL estructurales 15 (2,7%) y mosaicos 11 (2,3%). La trisomía 18 fue en ambos tipos de muestra la más frecuente (73,5%), seguida de trisomía 13 (24,2%) y trisomía 9 (2,3%). Se desglosan resultados conforme al tipo de TL, muestra, motivo de derivación, edad materna y edad gestacional. CONCLUSIONES: El cariograma confirma el diagnóstico de aneuploidías y aporta datos relevantes para el consejo genético. La cromosomopatía letal más frecuente fue la trisomía 18. Se observó que uno de cada cinco cariogramas referidos por anomalías congénitas y/o marcadores de aneuploidía revelaban una TL.

INTRODUCTION: In Chile, the technical standard of Law No. 21,030 of 2017 considers three aneuploidies as lethal; trisomies 9, 13 and 18, whose diagnosis is confirmed with a Karyotype. To date there is not a national registry of prenatal frequency of these pathologies. OBJECTIVE: To determine the frequency of trisomies 9, 13 and 18 in prenatal cytogenetic studies in samples of cells obtained with amniocentesis and cordocentesis, processed in the Cytogenetics Laboratory of the Universidad de Chile Clinical Hospital. MATERIALS AND METHODS: Descriptive and retrospective study of the results of karyotypes of amniotic fluid (LA) and fetal blood (SF) processed from January 2000 to December 2017. Results: 2,305 samples (402 of SF and 1,903 of LA) were included, of which 438 (19%) were lethal trisomies (TL), corresponding to free TL 416 (95%), structural TL 12 (2,7%) and mosaics 10 (2.3%). Trisomy 18 was the most frequent in both types of sample (73,5 %), followed by trisomy 13 (24,2%) and trisomy 9 (2.3%). RESULTS are shown according to the type of TL, sample, reason for referral, maternal age and gestational age. CONCLUSIONS: The karyotype confirms the diagnosis of aneuploidies and provides relevant data for genetic counseling. The most frequent lethal chromosomopathy was trisomy 18. It was observed that one in five karyotypes referred for congenital anomalies and / or aneuploidy markers revealed a TL.

Cell-free DNA screening for aneuploidies in 7113 pregnancies: single Italian centre study.

INTRODUCTION: Non-invasive prenatal testing (NIPT) using cell-free foetal DNA has been widely accepted in recent years for detecting common foetal chromosome aneuploidies, such as trisomies 13, 18 and 21, and sex chromosome aneuploidies. In this study, the practical clinical performance of our foetal DNA testing was evaluated for analysing all chromosome aberrations among 7113 pregnancies in Italy. METHODS: This study was a retrospective analysis of collected NIPT data from the Ion S5 next-generation sequencing platform obtained from Altamedica Medical Centre in Rome, Italy. RESULTS: In this study, NIPT showed 100% sensitivity and 99.9% specificity for trisomies 13, 18 and 21. Out of the 7113 samples analysed, 74 cases (1%) were positive by NIPT testing; foetal karyotyping and follow-up results validated 2 trisomy 13 cases, 5 trisomy 18 cases, 58 trisomy 21 cases and 10 sex chromosome aneuploidy cases. There were no false-negative results. CONCLUSION: In our hands, NIPT had high sensitivity and specificity for common chromosomal aneuploidies such as trisomies 13, 18 and 21.

Implementation of a Perinatal Hospice Program.

BACKGROUND: In 2017, the Nebraska Unicameral passed legislative bill 506, which required physicians to inform patients carrying fetuses diagnosed with a life-limiting anomaly of the option to enroll in a comprehensive perinatal hospice program. The bill also required the Department of Health & Human Services to provide information about statewide hospice programs. Families enrolled in hospice programs are better prepared for the birth and death of their child. This large academic medical center was listed on the registry but did not have a formal perinatal hospice program. PURPOSE: Implementation of a comprehensive perinatal hospice program. METHODS: The program was designed and implemented, beginning with the formation of an interdisciplinary team. Guidelines were developed for program referral, care conferences, team communication, and family follow-up. The team was educated. Electronic record documentation and order set were implemented. A data collection process was developed to track referrals and critical data points. RESULTS: The perinatal hospice program has been accepting referrals but has not had any qualifying referrals. IMPLICATIONS FOR PRACTICE: The development of an evidence-based guideline for referral that can improve referral consistency. While trisomy 13 and 18 diagnosis was historically considered life-limiting, these families now have the option of full intervention and transfer for specialists. IMPLICATIONS FOR RESEARCH: Future research will include collecting data from patients who could have benefited from hospice, including infants who were born 20 to 22 weeks, or for maternal reasons. Future research will evaluate the experience after bereavement, the hospice team's experience, and the effectiveness of the referral process.

Quantitative and qualitative Ductus Venosus blood flow evaluation in the screening for Trisomy 18 and 13 - suitability study.

OBJECTIVES: The objective of the paper is the suitability assessment of screening for Trisomy 18 and 13 on the basis of nuchal translucency (NT) measurement, Fetal Heart Rate (FHR), double test, quantitative [Ductus Venosus (DV) Pulsatility Index for Veins (PIV)] and qualitative (the A-wave assessment) blood flow evaluation in the DV. MATERIAL AND METHODS: The study was performed in 7296 singleton pregnancies. In each fetus NT, FHR, DV-PIV were examined. Double test from maternal blood was examined. These ultrasound and biochemical factors were in combined screening investigated. Additional doppler ultrasound markers such as abnormal a-wave in Ductus Venosus and Pusatility Index for Veins of Ductus Venosus were and their impact on Trisomies 18 and 13 screening were examined. RESULTS: Two groups of patients were compared - with chromosomal normal and chromosomal abnormalities - Trisomy 18 and 13. Detection Rate of Trisomies 18 and 13 at the risk cutoff 1/300 using combined screening was 90.2% and FPR was 6%. Detection Rates of examined chromosomal abnormalities using contingent screening were: 92.1% using DV abnormal a-wave and 94.84% using DV-PIV. FPR's for booths parameters 5.8% and 5.4% respectively. CONCLUSIONS: Quantitative analysis of the flow - assessment of DV-PIV in the first trimester significantly influences the improvement of screening values focusing on Trisomy 18 and 13 detection.

Perinatal Counseling Following a Diagnosis of Trisomy 13 or 18: Incorporating the Facts, Parental Values, and Maintaining Choices.

BACKGROUND: Families with a prenatal diagnosis of trisomy 13 or 18 are told many things, some true and some myths. They present with differing choices on how to proceed that may or may not be completely informed. PURPOSE: To provide the prenatal counselor with a review of the pertinent obstetrical and neonatal outcome data and ethical discussion to help them in supporting families with the correct information for counseling. METHODS/SEARCH STRATEGY: This article provides a review of the literature on facts and myths and provides reasonable outcome data to help families in decision making. FINDINGS/RESULTS: These disorders comprise a heterogeneous group regarding presentation, outcomes, and parental goals. The authors maintain that there needs to be balanced decision-making between parents and providers for the appropriate care for the woman and her infant. IMPLICATIONS FOR PRACTICE: Awareness of this literature can help ensure that prenatal and palliative care consultation incorporates the appropriate facts and parental values and in the end supports differing choices that can support the infant's interests.

Prenatal ultrasound findings of holoprosencephaly spectrum: Unusual associations.

OBJECTIVE: The objective of this study is to evaluate the prenatal diagnosis, postnatal characteristics, and the spectrum of associated findings in fetuses with holoprosencephaly (HPE). METHODS: Fetal neurosonograms, postnatal assessment, and chromosomal analysis were performed in a cohort of 25 fetuses with HPE. RESULTS: The prevalence of HPE in high-risk pregnancies was 4.4:10 000. The alobar subtype was the most frequently encountered, with 17 cases (68%). Interestingly, among them, four cases (16%) presented with the rare agnathia-otocephaly complex. Chromosomal abnormalities were detected in 11 cases (44%), the most frequent being trisomy 13 in seven cases (five alobar, one semilobar, and one lobar HPE), followed by trisomy 18 in two cases with semilobar HPE. One case of alobar HPE had 45, XX, t(18;22) (q10;q10), -18p karyotyping, and one case of semilobar HPE was associated with triploidy. Facial malformations in HPE spectrum ranged from cyclopia, proboscis, and arrhinia that were associated with the alobar subtype to hypotelorism and median cleft that were frequent among the semilobar and lobar subtypes. Associated neural tube defects were identified in 12% of cases. CONCLUSION: Our study illustrates the clinical and genetic heterogeneity of HPE and describes different chromosomal abnormalities associated with HPE.

Noninvasive prenatal detection of hemoglobin Bart hydrops fetalis via maternal plasma dispensed with parental haplotyping using the semiconductor sequencing platform.

BACKGROUND: Thalassemia is one of the most common monogenetic diseases in the south of China and Southeast Asia. Hemoglobin Bart's hydrops fetalis syndrome was caused by a homozygous Southeast Asian deletion (-/-) in the HBA gene. Few studies have proved the potential of screen for Bart's hydrops fetalis using fetal cell-free DNA. However, the number of cases is still relatively small. Clinical trials of large samples would be needed. OBJECTIVE: In this study, we aimed to develop a noninvasive method of target-captured sequencing and genotyping by the Bayesian method using cell-free fetal DNA to identify the fetal genotype in pregnant women who are at risk of having hemoglobin Bart hydrops fetalis in a large-scale study. STUDY DESIGN: In total, 192,173 couples from 30 hospitals were enrolled in our study and 878 couples were recruited, among whom both the pregnant women and their husbands were detected to be carriers of Southeast Asian type (-/αα) of α-thalassemia. Prenatal diagnosis was performed by chorionic villus sampling, amniocentesis, or cordocentesis using gap-polymerase chain reaction considered as the golden standard. RESULTS: As a result, we found that the sensitivity and specificity of our noninvasive method were 98.81% and 94.72%, respectively, in the training set as well as 100% and 99.31%, respectively, in the testing set. Moreover, our method could identify all of 885 maternal samples with the Southeast Asian carrier and 36 trisomy samples with 100% of sensitivity in T13, T18, and T21 and 99.89% (1 of 917) and 99.88% (1 of 888) of specificity in T18 and T21, respectively. CONCLUSION: Our method opens the possibility of early screening for maternal genotyping of α-thalassemia, fetal aneuploidies in chromosomes 13/18/21, and hemoglobin Bart hydrops fetalis detection in 1 tube of maternal plasma.

Fetal umbilical cord cyst may evolve to omphalocele during pregnancy.

Omphalocele is rarely complicated by umbilical cord cysts. In our case, an umbilical cord cyst and fetal ascites were detected at 26 weeks' gestation in a fetus with trisomy 13. This changed to omphalocele with subsequently absorbed fetal ascites at 35 weeks' gestation. We propose two hypotheses. The abdominal wall may have been physically pierced or an omphalocele might have preexisted, and the intestinal tract in the hernia sac was pushed by fetal ascites.