Incidence Of Chromosomal Abnormalities Research Articles

Etiologic evaluation and pregnancy outcomes of fetal growth restriction (FGR) associated with structural malformations

This study aimed to evaluate the etiology and pregnancy outcomes of fetuses underwent invasive prenatal diagnosis for fetal growth restriction (FGR) accompanied by structural malformations. Data from 130 pregnancies referred for prenatal diagnosis for FGR accompanied by structural malformations were obtained between July 2011 and July 2023. Traditional karyotyping was conducted for all the subjects. A total of 37 (28.5%) cases of chromosomal abnormalities were detected by karyotyping, including 30 cases of numerical anomalies and seven cases of unbalanced structural anomalies. Trisomy 18 was the most common abnormalities, accounting for 51.4%, significantly higher than any other chromosomal abnormality. The cohort was predominantly comprised of early-onset FGR (88.5%) compared to late-onset FGR (11.5%). The incidences of chromosomal abnormalities in this two groups were 29.6% (34/115) and 20.0% (3/15), respectively (p > 0.05). The majority (74.6%, 97/130) of the cohort were affected by a single system malformation, with chromosomal abnormalities found in 19.6% (19/97) of cases. In pregnancies of structural malformations involving two and multiple systems, the frequencies were 56.5% (13/23), and 50.0% (5/10), respectively. Single nucleotide polymorphism array (SNP array) was performed in parallel for 65 cases, revealing additional 7.7% cases of copy number variants (CNVs) compared to karyotyping. Polymerase chain reaction (PCR) was used for detection of cytomegalovirus (CMV) DNA in 92 cases. All fetuses with FGR associated with two or more system malformations were either terminated or stillborn, irrespective of chromosomal aberrations. Conversely, 71.8% of pregnancies with a single-system malformation and normal genetic testing results resulted in live births. Furthermore, two (2.2%) cases tested positive for CMV DNA, leading to one termination and one case of serious developmental disorder after birth. Our study suggests that structural malformations associated with FGR are more likely to affect a single organ system. When multiple systems are involved, the incidence of chromosomal abnormalities and termination rates are notably high. We advocate for the use of CMA and CMV DNA examinations in FGR cases undergo invasive prenatal diagnosis, as these tests can provide valuable insights for etiological exploration and pregnancy management guidance.

Developmental, cytogenetic and epigenetic consequences of removing complex proteins and adding melatonin during in vitro maturation of bovine oocytes.

In vitro maturation (IVM) of germinal vesicle intact oocytes prior to in vitro fertilization (IVF) is practiced widely in animals. In human assisted reproduction it is generally reserved for fertility preservation or where ovarian stimulation is contraindicated. Standard practice incorporates complex proteins (CP), in the form of serum and/or albumin, into IVM media to mimic the ovarian follicle environment. However, the undefined nature of CP, together with batch variation and ethical concerns regarding their origin, necessitate the development of more defined formulations. A known component of follicular fluid, melatonin, has multifaceted roles including that of a metabolic regulator and antioxidant. In certain circumstances it can enhance oocyte maturation. At this stage in development, the germinal-vesicle intact oocyte is prone to aneuploidy and epigenetic dysregulation. To determine the developmental, cytogenetic and epigenetic consequences of removing CP and including melatonin during bovine IVM. The study comprised a 2 x 2 factorial arrangement comparing (i) the inclusion or exclusion of CP, and (ii) the addition (100 nM) or omission of melatonin, during IVM. Cumulus-oocyte complexes (COCs) were retrieved from stimulated cycles. Following IVM and IVF, putative zygotes were cultured to Day 8 in standard media. RNAseq was performed on isolated cumulus cells, cytogenetic analyses (SNP-based algorithms) on isolated trophectoderm cells, and DNA methylation analysis (reduced representation bisulfite sequencing) on isolated cells of the inner-cell mass. Removal of CP during IVM led to modest reductions in blastocyst development, whilst added melatonin was beneficial in the presence but detrimental in the absence of CP. The composition of IVM media did not affect the nature or incidence of chromosomal abnormalities but cumulus-cell transcript expression indicated altered metabolism (primarily lipid) in COCs. These effects preceded the establishment of distinct metabolic and epigenetic signatures several days later in expanded and hatching blastocysts. These findings highlight the importance of lipid, particularly sterol, metabolism by the COC during IVM. They lay the foundation for future studies that seek to develop chemically defined systems of IVM for the generation of transferrable embryos that are both cytogenetically and epigenetically normal.

Chromosomal abnormalities and structural defects in fetuses with increased nuchal translucency at a Chinese tertiary medical center.

To explore the pregnancy outcomes of fetuses with increased NT thickness. This was a retrospective study of fetuses with increased NT (≥95th centile) at 11-14 weeks of gestation between January 2020 and November 2020. Among 264 fetuses with increased NT, the median of CRL and NT was 61.2 mm and 2.41 mm. Among them, 132 pregnancy women chose invasive prenatal diagnosis (43 cases of chorionic villus sampling (CVS), 89 cases of amniocentesis). Eventually, 16 cases of chromosomal abnormalities were discovered, including 6 cases (6.4%) of trisomy 21, 4 cases (3%) of trisomy 18, 1 case (0.8%) of 45, XO, 1 case (0.8%) of 47, XXY and 4 cases (3.03%) of CNV abnormalities. The major structural defects included hydrops (6.4%), cardiac defects (3%), and urinary anomalies (2.7%). The incidences of chromosomal abnormalities and structural defects in the NT < 2.5 mm group were 1.3 and 6%, while the incidences were 8.8 and 28.9% in the NT≥2.5 group. Increased NT was associated with high risk of chromosomal abnormalities and structural anomalies. Chromosomal abnormalities and structural defects could be detected when NT thickness was between 95th centile and 2.5 mm.

Comparison of results of prenatal diagnosis by different techniques for fetuses with increased nuchal translucency

To assess the value of chromosomal microarray analysis (CMA) and trio-whole exome sequencing (trio-WES) for fetuses with increased nuchal translucency (NT) thickness. Sixty two pregnant women who had visited Urumqi Maternal and Child Care Health Hospital between June 2018 and June 2020 for NT ≥ 3.0 mm at 11 ~ 13+6 gestational weeks were selected as study subjects. Relevant clinical data were collected. The patients were divided into 3.0 ~ ＜3.5 mm (n = 33) and ≥3.5 mm groups (n = 29). Chromosome karyotyping analysis and chromosomal microarray analysis were carried out. And trio-WES analysis was performed on 15 samples with NT thickening but negative CMA results. The distribution and incidence of chromosomal abnormalities in the two groups were compared by using chi-square test. The median age of the pregnant women was 29 years old (22 ~ 41 years old), the median thickness of NT was 3.4 mm (3.0 ~ 9.1 mm), and the median gestational age at the detection was 13+4 weeks (11+5 ~ 13+6 weeks). Chromosome karyotyping analysis has detected 12 cases of aneuploidies and 1 case of derivative chromosome. The detection rate was 20.97% (13/62). CMA has detected 12 cases of aneuploidies, 1 case of pathogenic CNV and 5 cases of variant of uncertain significance (VUS), with a detection rate of 29.03% (18/62). The aneuploidy rate for the NT ≥ 3.5 mm group was higher than that for the 3.0 ≤ NT < 3.5 mm group [3.03% (1/33) vs. 41.38% (12/29), χ² = 13.698, P < 0.001]. There was no statistically significant difference between the two groups in the detection rate of fetal pathogenic CNV and VUS (χ² = 0.028, P > 0.05). Trio-WES analysis of 15 samples with negative CMA result and no structural abnormality has identified 6 heterozygous variants, including SOS1: c.3542C>T (p.A1181V) and c.3817C>G (p.L1273V), COL2A1: c.436C>T (p.P146S) and c.3700G>A (p.D1234N), LZTR1: c.1496T>C (p.V499A), and BRAF: c.64G>A (p.D22N), respectively. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), all of the variants were rated as VUS. NT thickening can indicate chromosome abnormality, and CMA and trio-WES may be used for the prenatal diagnosis.

Clinical Value of Genetic Susceptibility Genes for Myeloid Neoplasm in Myeloproliferative Neoplasm

To investigate the influence of genetic susceptibility genes for myeloid tumors on the clinical characteristics of patients with myeloproliferative neoplasm (MPN). Two hundred and thirty-two patients with MPN diagnosed at the Second Hospital of Tianjin Medical University from September 2017 to December 2021 were collected, myeloid neoplasm-related genes were detected by targeted next-generation sequencing, and germline mutations were verified. The clinical characteristics and prognosis of MPN patients with germlines mutations in the genetic susceptibility gene for myeloid neoplasm were analyzed. The germline mutation carrier rate of myeloid neoplasm genetic susceptibility gene in MPN patients was 21.6% (50/232), and the PV, ET and PMF patients carrying germline mutations of genetic susceptibility gene for myeloid neoplasm were 25/114 (21.9%), 8/69 (11.6%) and 17/49 (34.7%), respectively, among which PMF patients had the highest carrier rate (P=0.01) and were older (P=0.02). The incidence of chromosomal abnormalities in MPN patients carrying the genetic susceptibitity genes for myeloid neoplasm was higher than that in the non-carrier group (26.5% vs 11.8%, P=0.05). Germline mutations in the genetic susceptibility gene of myeloid neoplasm in MPN patients were mainly concentrated in the RAS pathway, and patients with germline mutations in the genetic susceptibility gene of myeloid neoplasm associated with the RAS pathway had shorter survival without AML progression (P<0.0001). The overall survival time in MPN patients with CBL and TP53 germline mutations was shorter than that of non-carrier group (P=0.001; P=0.043). In MPN, PMF patients are more likely to carry germline mutations in the genetic susceptibility gene for myeloid neoplasm. MPN patients with germline mutations carring the genetic susceptibility gene for myeloid neoplasm are prone to chromosomal abnormalities; Patients with MPN who have germline mutations in the genetic susceptibility gene for myeloid neoplasm in the RAS pathway are more likely to develop AML; CBL and TP53 germline mutations affect the overall survival of MPN patients.

Application of Complete Prenatal Diagnosis in Fetal Ultrasound Abnormalities.

To investigate the value of prenatal diagnosis in fetal ultrasound abnormalities. Amniotic fluid samples of pregnant women who underwent invasive amniocentesis for ultrasound examination suggestive of fetal ultrasound structural abnormalities and soft markers of abnormalities during pregnancy from January 2016 to June 2021 at the Prenatal Diagnostic Center of Putian College Hospital were collected for amniotic fluid cell culture and G manifest band karyotype analysis. (1) Most pregnant women with ultrasound abnormalities were delivered at the age of 23 to 32 years. (2) There were 66 cases of abnormal karyotype with an abnormal incidence of 9.64% (66/685), with chromosomal number abnormalities predominating. (3) Fetal ultrasound abnormalities are mainly soft markers of abnormalities. (4) The comparison of ultrasound abnormalities in the low and high maternal-fetal age groups was not statis-tically significant. (1) Fetal ultrasound abnormalities are mainly soft markers of abnormalities. (2) The rate of fetal chromosomal abnormalities was the highest among the soft ultrasound indicators with NT thickening. (3) The incidence of fetal ultrasound abnormalities did not increase with increasing age. There was no statistical difference in the incidence of chromosomal abnormalities between the low age group and the high age group. (4) Fetal ultrasound testing provides a scientific and accurate basis for clinical heritage counseling and rebirth counseling, especially for chromosomal aneuploidy number abnormalities.

PMON33 Non-Syndromic SRY Negative 46 XX Testicular Disorder of Sex Development (DSD): A Rare Cause of Infertility

Abstract Introduction Male infertility can be categorized as endocrine and systemic disorders, primary testicular defects in spermatogenesis, sperm transport disorders and idiopathic male infertility. Chromosomal abnormalities are one of the primary testicular defects. The overall incidence of chromosome abnormalities in infertile men is estimated to be around 5.8%. XX male is a rare sex chromosomal disorder in infertile men. We present case of a young patient with infertility, azoospermia, hypergonadotropic hypogonadism and classical (46, XX) karyotype with negative FISH and SRY gene. Case report: 28-Year-old gentleman was referred to adult endocrinology clinic as part of work up for infertility. Initial work up included 2 semen analyses which were consistent with azoospermia. Examination revealed height 180 cm, weight 77 kg, a body mass index 24 kg/m2, normal phenotypic male without gynecomastia and had normal male pattern hair distribution. Genital examination showed normal male phallus without hypospadias, a hypoplastic scrotum, bilateral firm testes, with no varicocele or hydrocele. Labs were suggestive of compensated primary hypogonadism (FSH 47.9 mIU/ml, LH 20.4 mIU/ml, total testosterone 397.9 ng/dl by LC/MS, free testosterone 15.76 ng/dl by equilibrium dialysis, Inhibin B &amp;lt; 10 pg/ml, and anti-Mullerian hormone 0.390 ng/ml. Given normal testosterone levels, he was not started on testosterone replacement. Karyotype analysis revealed 46 XX and FISH was negative for SRY gene. CT imaging of abdomen and pelvis did not reveal any Mullerian structures, prostrate and seminal vesicles reported as normal. Patient met with a Urologist and was informed that testicular sperm extraction will not be a possibility for him. Patient had a detailed consultation with a geneticist for genetic and family counseling. Chromosome microarray analysis was obtained and was normal. Invitae Disorders of sex development (DSD) panel obtained for genetic sequencing of 53 genes including SOX-9, DHH, WNT4, WT1, was found to be non-diagnostic. Conclusion and Discussion SRY negative 46 XX male is a DSD and a rare genetic cause of male factor infertility, with a discrepancy between genotype and phenotypic sex. In the case presented, genetic work up for potential etiologies has been unrevealing. Further studies are needed to identify the genetic causes of the SRY negative 46 XX male phenotype. Physicians involved in care of these patients should orient with clinical management and prognosis. For Classical 46 XX Males seeking fertility, the current options include invitro-fertilization with donor sperm or adoption only. Testosterone replacement should be considered to correct hypogonadism for physical and sexual well-being. Genetic consultation should be sought in all these cases. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

PMON33 Non-Syndromic SRY Negative 46 XX Testicular Disorder of Sex Development (DSD); A rare cause of Infertility

Abstract Introduction Male infertility can be categorized as endocrine and systemic disorders, primary testicular defects in spermatogenesis, sperm transport disorders and idiopathic male infertility. Chromosomal abnormalities are one of the primary testicular defects. The overall incidence of chromosome abnormalities in infertile men is estimated to be around 5.8%. XX male is a rare sex chromosomal disorder in infertile men. We present case of a young patient with infertility, azoospermia, hypergonadotropic hypogonadism and classical (46, XX) karyotype with negative FISH and SRY gene. Case report: 28-Year-old gentleman was referred to adult endocrinology clinic as part of work up for infertility. Initial work up included 2 semen analyses which were consistent with azoospermia. Examination revealed height 180 cm, weight 77 kg, a body mass index 24 kg/m2, normal phenotypic male without gynecomastia and had normal male pattern hair distribution. Genital examination showed normal male phallus without hypospadias, a hypoplastic scrotum, bilateral firm testes, with no varicocele or hydrocele. Labs were suggestive of compensated primary hypogonadism (FSH 47.9 mIU/ml, LH 20.4 mIU/ml, total testosterone 397.9 ng/dl by LC/MS, free testosterone 15.76 ng/dl by equilibrium dialysis, Inhibin B &amp;lt; 10 pg/ml, and anti-Mullerian hormone 0.390 ng/ml. Given normal testosterone levels, he was not started on testosterone replacement. Karyotype analysis revealed 46 XX and FISH was negative for SRY gene. CT imaging of abdomen and pelvis did not reveal any Mullerian structures, prostrate and seminal vesicles reported as normal. Patient met with a Urologist and was informed that testicular sperm extraction will not be a possibility for him. Patient had a detailed consultation with a geneticist for genetic and family counseling. Chromosome microarray analysis was obtained and was normal. Invitae Disorders of sex development (DSD) panel obtained for genetic sequencing of 53 genes including SOX-9, DHH, WNT4, WT1, was found to be non-diagnostic. Conclusion and Discussion SRY negative 46 XX male is a DSD and a rare genetic cause of male factor infertility, with a discrepancy between genotype and phenotypic sex. In the case presented, genetic work up for potential etiologies has been unrevealing. Further studies are needed to identify the genetic causes of the SRY negative 46 XX male phenotype. Physicians involved in care of these patients should orient with clinical management and prognosis. For Classical 46 XX Males seeking fertility, the current options include invitro-fertilization with donor sperm or adoption only. Testosterone replacement should be considered to correct hypogonadism for physical and sexual well-being. Genetic consultation should be sought in all these cases. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

EP11.02: Incidence of chromosomal abnormalities in fetuses with ventriculomegaly

EP11.02: Incidence of chromosomal abnormalities in fetuses with ventriculomegaly

Analysis results of 169 cases of chorionic villus samples of missed abortion using high throughput sequencing.

This study aimed to evaluate the use of high-throughput sequencing (HTS) technology to detect chromosomes in chorionic villus samples of missed abortion embryos and investigate its utility in the genetic diagnosis of missed abortion. HTS was used to assess chorionic villus samples obtained from 169 patients with missed abortions from August 2020 to March 2022, at the Second Affiliated Hospital of Guangxi Medical University. The test results were statistically analyzed. To investigate the impact of advanced age on the incidence of chromosomal abnormalities, the patients were divided into two groups: elderly (≥35 years) and nonelderly pregnant women (<35 years). (1) Among the samples of 169 patients, 100 (59.17%) cases of chromosomal abnormalities were detected. Among these 100, 90 (90%) had chromosomal numerical abnormalities and 10 (10%) had chromosomal structural abnormalities. (2) Chromosomal numerical abnormality was abnormalities mainly included aneuploidy (92.22%, 83/90), with trisomy (62.22%, 56/90) and monosomy (22.22%, 20/90) accounting for the majority. The top three numerical abnormalities included 18 cases of Turner syndrome (monosomy X; 20%, 18/90), 10 cases of trisomy 16 (11.11%, 10/90), and 10 cases of trisomy 22 (11.11%, 10/90). (3) Villous chromosomal abnormalities were found in 48 (70.59%) elderly pregnant women, and 52 (51.48%) nonelderly pregnant women, with statistically significant differences (p < 0.05). (1) Chromosomal abnormality is an important cause of missed abortion, it majorly includes chromosomal numerical abnormality, of which most cases are of aneuploidy. (2) Advanced age may increase the risk of embryonic chromosomal abnormalities. (3) Villus chromosome detection using HTS has a positive value and can be used for analyzing and determining the causes of missed abortion.

A Retrospective Cohort Analysis of the Genetic Assay Results of Foetuses with Isolated and Nonisolated Umbilical Cord Cyst.

ObjectiveTo analyse the risk of clinical chromosomal abnormalities in foetuses with umbilical cord cysts.MethodsData from all genetic assays that were performed as part of invasive prenatal diagnoses of umbilical cord cysts between October 2014 and June 2021 were retrospectively collected from Guangdong Women and Children Hospital. We compared the differences in genetic assay findings in isolated and nonisolated umbilical cord cyst cohorts.ResultsA total of 49 singleton pregnancies and 2 foetuses that were one of the cotwins in monochorionic twin pregnancies were enrolled in the cohort; 20 isolated and 31 nonisolated umbilical cord cysts were identified in the cohort. One foetus (5%, 1/20) in the isolated umbilical cord cyst group showed chromosomal abnormalities and 17p12 microduplication. Twelve cases (38.7%, 12/31) of chromosomal abnormalities, including seven cases of trisomy 18, two cases of trisomy 13 and three cases of microdeletion, were identified in the nonisolated umbilical cord cyst group. The incidences of chromosomal abnormalities between the two groups were significantly different (1/20, 5% vs 13/31, 38.7%, p=0.003). There was no relative pathological medical exome sequencing finding in the three foetuses suffering from nonisolated umbilical cord cysts whose parents chose to undergo chromosomal microarray analysis (CMA) and medical exome sequencing.ConclusionThis retrospective cohort study evaluated the value of CMA in foetuses with umbilical cord cysts and suggested that copy number variants (CNVs) may be the basic genetic aetiological factors that should be considered for diagnostic evaluation. We recommended CMA as a basic genetic evaluation in cases of umbilical cord cysts, especially in nonisolated cases.

Recurrent pregnancy loss: fewer chromosomal abnormalities in products of conception? a meta-analysis.

To compare the prevalence of chromosomal abnormalities detected in products of conception (POCs) between recurrent pregnancy loss and sporadic pregnancy loss. A systematic search was performed in the PubMed and Embase databases from inception to December 31, 2020. Relevant studies analysing the association between the number of pregnancy losses and the incidence of chromosomal abnormalities were included. Independent data extraction was conducted and study quality was assessed. Meta-analyses were carried out to calculate odds ratios by using fixed- or random-effects models according to statistical homogeneity. A total of 8320 POCs in 19 studies were identified for the meta-analyses. The incidence of chromosomal abnormalities in sporadic pregnancy loss was significantly higher than that in recurrent pregnancy loss. In subgroup analyses, the following studies reported a high incidence of abnormal outcomes of sporadic pregnancy loss: studies with ≥ 300 samples, studies published before 2014, studies conducted in European and American countries, and studies with analyses using conventional karyotype techniques. Moreover, the incidence of chromosomal abnormalities in women with two pregnancy losses was significantly higher than that in women with three or more pregnancy losses. However, there was no difference in the distribution of abnormal types between sporadic and recurrent pregnancy loss or between two and three or more pregnancy losses. The prevalence of chromosomal abnormalities detected in POCs was lower in recurrent pregnancy loss than in sporadic pregnancy loss, and decreased with an increasing number of pregnancy losses.

Prenatal diagnosis and clinical outcomes of 297 fetuses with conotruncal defects

Objective: To analyze the prenatal diagnosis results and pregnancy outcomes of conotruncal defects (CTD) fetuses, and to explore the correlation between the CTD and chromosome diseases. Methods: A total of 297 cases of invasive prenatal diagnosis and chromosome analysis were collected at the Prenatal Diagnosis Center of Guangzhou Women and Children's Medical Center due to CTD from January 1st, 2011 to December 31th, 2019. According to ultrasonic diagnosis, CTD fetuses were divided into 6 subtypes: tetralogy of Fallot (109 cases), pulmonary atresia (30 cases), transposition of the great arteries (77 cases), double outlet right ventricle (53 cases), truncus arteriosus (14 cases) and interrupted aortic arch (14 cases). According to whether they were combined with intracardiac or extracardiac abnormalities, they were divided into simple group (134 cases), combined with other intracardiac abnormalities group (86 cases), combined with extracardiac abnormalities group (20 cases), combined with intracardiac and extracardiac abnormalities group (37 cases) and only combined with ultrasound soft marker group (20 cases), the last 4 groups were referred as non-simple types. The chromosome test results and pregnancy outcomes of each type and group were analyzed retrospectively. Results: Among the 297 CTD fetuses, the chromosome abnormality rate was 17.5% (52/297). There were 21 cases of abnormal chromosome number, 28 cases of pathogenetic copy number variantions and 3 cases of mosaics. All the 19 cases of micropathogenic fragments smaller than 5 Mb were detected by chromosomal microarray analysis (CMA). Among all the subtypes of CTD, the chromosomal abnormality rate of truncus arteriosus was the highest, at 7/14; while the rate of transposition of the great arteries was the lowest, at 5.2% (4/77). There were significant differences in the rate of chromosomal abnormalities between simple and non-simple types [10.4% (14/134) vs 23.3% (38/163); χ²=8.428, P=0.004]. In each group, the chromosomal abnormality rate was the highest in the combined with intracardiac and extracardiac abnormalities group, at 37.8% (14/37), and the lowest in the simple group, at 10.4% (14/134). There was no significant difference in the rate of chromosomal abnormalities in all subtypes of simple group (all P>0.05). Among 112 cases of live birth, 1 case was 22q11.2 microdeletion syndrome, 5 cases of postnatal clinical diagnosis and prenatal ultrasound diagnosis were not completely consistent, 5 cases died after birth. Conclusions: The incidence of chromosomal abnormalities is high in fetuses with CTD. CTD fetuses with concurrent extrapardiac malformations are more likely to incorporate chromosomal abnormalities. CMA technology could be used as a first-line genetic detection method for CTD. After excluding chromosomal abnormalities, most of the children with CTD have good prognosis.

Correlation of Maternal Age and Chromosomal Abnormality in Products of Conception- A Single Centric Study

Purpose: The purpose of this study is to find out the types and incidence rate of chromosomal abnormalities and the relationship between maternal age and chromosomal abnormality in products of conception by retrospective analysis. Method: Karyotype study using standard GTG banding and FISH study for aneuploidy detection was done from products of conception samples. Results: A total of 513 cases of products of conception were studied retrospectively. 98 cases were studied by conventional cytogenetic technique and 415 cases were studied by a FISH method. The chromosomal abnormality was observed in 97 cases (18.91%). Trisomy was found to be a major chromosomal abnormality amongst the cases studied, followed by triploidy and monosomy. A higher incidence of chromosomal abnormality was found in women with advanced maternal age as compared to the maternal age less than 35 years.

Prevalence of common aneuploidy in twin pregnancies

The incidence of chromosomal abnormalities in twin pregnancies is not well-studied. In this retrospective study, we investigated the frequency of chromosomal abnormalities in twin pregnancies and compared the incidence of chromosomal abnormalities in dichorionic diamniotic (DD) and monochorionic diamniotic (MD) twins. We used data from 57 clinical facilities across Japan. Twin pregnancies of more than 12 weeks of gestation managed between January 2016 and December 2018 were included in the study. A total of 2899 and 1908 cases of DD and MD twins, respectively, were reported, and the incidence of chromosomal abnormalities in one or both fetuses was 0.9% (25/2899) and 0.2% (4/1908) in each group (p = 0.004). In this study, the most common chromosomal abnormality was trisomy 21 (51.7% [15/29]), followed by trisomy 18 (13.8% [4/29]) and trisomy 13 (6.9% [2/29]). The incidence of trisomy 21 in MD twins was lower than that in DD twins (0.05% vs. 0.5%, p = 0.007). Trisomy 21 was less common in MD twins, even when compared with the expected incidence in singletons (0.05% vs. 0.3%, RR 0.15 [95% CI 0.04–0.68]). The risk of chromosomal abnormality decreases in twin pregnancies, especially in MD twins.

Analysis of the results of chromosomal trisomies 21, 18 and 13 screening among 40 628 women by non-invasive prenatal testing

To assess the clinical value of non-invasive prenatal testing (NIPT) for the screening of trisomy and copy number variations (CNVs) of chromosomes 21, 18 and 13. From January 2015 to December 2019, 40 628 pregnant women underwent NIPT testing using high-throughput sequencing and bioinformatics analysis to test the cell-free fetal DNA in maternal plasma. High-risk pregnant women underwent invasive prenatal diagnosis, while low-risk ones were followed up by telephone. The three most common indications included intermediate risk of serological screening, high risk of serological screening and advanced maternal age. Among all pregnant women, 257 cases were detected as trisomy 21, 18 and 13 (170, 49 and 38 cases, respectively). 227 cases chose invasive prenatal diagnosis, with respectively 122, 28 and 10 cases confirmed. The positive predictive value (PPV) was 81.33% (122/150), 65.12% (28/43), 29.41% (10/34), respectively. Two false negative cases of trisomy 18 were found during follow-up. Meanwhile, NIPT has detected 46 cases (15, 16 and 15 cases, respectively) CNVs on chromosomes 21, 18 and 13, among which 37 cases underwent invasive prenatal diagnosis. There were 5, 3 and 5 positive cases, which yielded a PPV of 41.67% (5/12), 25%(3/12) and 33.33%(5/15), respectively. Two other chromosome CNVs were accidentally discovered among the false positive samples. The incidence of chromosomal abnormalities in the serological screening high-risk group was 52.02%, which was significantly higher than other groups. NIPT has a high sensitivity and specificity for the screening of trisomies 21, 18 and 13, while its accuracy for detecting CNVs of chromosomes 21, 18 and 13 needs to be improved. As a screening method, NIPT has a great clinical value, though there are still limitations of false positive and false negative results.Comprehensive pre- and post-test genetic counseling should be provided to the patients.

P–524 Is polycystic ovary syndrome really a risk factor for embryonic chromosomal aberrations? A multicenter retrospective cohort study

Abstract Study question Does the rate of embryonic chromosomal aberrations increase in the setting of PCOS independent of maternal age and BMI? Summary answer Controlling for maternal age and BMI, embryonic chromosomal aberration rate was not significantly different with controlled women undergoing preimplantation genetic testing for monogenic defects (PGT-M). What is known already It has been reported that women with PCOS have higher risk of early spontaneous pregnancy loss, and it is well known that embryonic chromosomal abnormalities play an important role as a direct factor. However, whether PCOS women have increased risk of embryonic chromosomal aberrations remains inconclusive. Study design, size, duration A multicenter retrospective cohort study was undertaken examining the incidence of chromosomal abnormalities in blastocysts using next-generation sequencing (NGS) for women undergoing PGT-M with and without PCOS (1398 PGT cycles, 5577 blastocysts) from 3 university-affiliated IVF centers between 2015 and 2019. Participants/materials, setting, methods: The blastocyst formation rate and the incidence of chromosomal abnormalities were compared between 163 PCOS women and 1235 non-PCOS women. Main results and the role of chance: Stratification analysis by maternal age with matched BMI showed no differences with regard to blastocyst formation rates for women with and without PCOS aged 20–29y (55.0% vs. 58.5%), 30–34y (54.7% vs. 58.9%) and &amp;gt;35y (56.7% vs. 52.4%), P &amp;gt; 0.05. The total embryonic chromosomal aberration rates for women aged 20–29y, 30–34y and &amp;gt;35y with and without PCOS were were also comparable, which were respectively 121/331 (36.4%) vs. 496/1209 (41.0%); 89/251 (35.5%) vs. 903/2175 (41.5%) and 72/130 (55.4%) vs. 789/1481 (53.3%), P &amp;gt; 0.05. Multivariate regression showed that controlling for maternal age and BMI, PCOS were not an independent risk factor for embryonic chromosomal abnormalities (OR = 0.89, 95% CI = 0.62 ∼ 1.35, P = 0.73). Limitations, reasons for caution The study is mainly limited by its retrospective design and relatively smaller sample size for PCOS group which carries inherent potential for bias (i.e. misclassifification and errors due to inadequate clinical notes). Wider implications of the findings: Our results indicated that chromosomal abnormalities might not be the most important causal factor for the increased risk of early pregnancy loss for women with PCOS. By contrary, the non-chromosomal embryonic aberrations and/or maternal intrauterine factors could play more important role and needs to be clarifified Trial registration number not applicable’

P–566 Advanced paternal age can influence aneuploidy rate in egg donation cycles with poor sperm quality

Abstract Study question Could advanced paternal age influences the embryos aneuploidy rate in eggs donation cycles with poor sperm quality? Summary answer In case of severe male factors increased paternal age can affect embryos aneuploidy rate in egg donation cycles. What is known already While the impact of advanced maternal age on reproductive is well understood, the effect of paternal age on reproductive function is controversial. Many studies have shown that Advanced Paternal Age (APA) could impact on male fertility potential affecting testicular function and sperm quality. Moreover, APA also has been associated with increased epigenetics changes and DNA mutations. Increased paternal age could be associated with different types of disorders such as autism, schizopherenia and bipolar disorders. Egg donation cycles, controlling female variables, represent the ideal model for the study of the impact of paternal age on reproductive outcomes. Study design, size, duration We retrospectively analyzed 43 egg donation cycles (October 2014-January 2020) with ≥ 50% survival rate of vitrified/warmed oocyte. Only cycles with poor sperm quality were considered. Cycles were divided in two GROUPS: group–1 included male paternal age ≤ 45 while group–2 included male paternal age &amp;gt;45. Data, shown as avarage±SD, were analyzed with Chi square or Student-t test. Participants/materials, setting, methods Group–1 included 20 cycles and 219 oocytes, male age was 40,89 ±6.12; Group–2 included 17 cycles and 173 oocytes, male age was 51±6.06. Respectively, in Group 1 and in Group 2, donor age were 22.4±2.65 and 24.8±3.88 (NS). All oocytes were injected with abnormal sperm samples according to WHO 2010. Embryos were cultured in time-lapse system until blastocyst stage. Trophectoderm biopsy and PGT-A analysis were performed according to standardized laboratory protocols. Main results and the role of chance Oocytes survival rates in Group1 and 2 were 86% (188/219) and 90.7% (157/173) (NS), respectively. Fertilization rates in Group1 and –2 were 71.42 (135/189) and 73.45% (119/162) (NS), respectively. The total number of obtained embryos (transferred + frozen) were 81 and 801 in Group–1 and –2, respectively. The rates of obtained embryos per reiceved occytes were 37% (81/219) and 46.24% (80/173) in Group–1 and –2 (p &amp;lt; 0.7), respectively. The PGT-A analysis showed 38.7% (31/80) and 31.17% (24/77) of euploid (NS) and 25% (20/80)and 42.85% (33/77) of aneuploid embryos (P &amp;lt; 0.05) in Group–1 and –2, respectively. Mosaic embryos were 33.5% (26/80) and 27.27%(21/77), in Group–1 and –2, respectively. (NS). These results indicate that in presence of severe male factor, advanced paternal age could increase embryos aneuploidy rate raising incidence of chromosomal abnormalities. Limitations, reasons for caution Each donor was stimulated with different protocols according to her history and hormones levels. Nothing is known about which type of sperm parameters (semen amount, morphology or motility) have a major impact when focusing on the embryos genetic outcome. Wider implications of the findings: To better known the effect of APA, it could be necessary identify embryos chromosomal abnormalities and the correlation with specific sperm parameters. Further studies should be done to confirm the APA effect in patients with severe male factors and define a cut-off male age where PGT-A should be recommended. Trial registration number Not applicable

Molecular Cytogenetic Study in Patients with Acute Lymphoblastic Leukemia (ALL) in Erbil Province

Background: Acute lymphoblastic leukemia (ALL) is the most common malignancy in children and is also important in older adults. Chromosome number or structure abnormalities are seen in approximately 90% of children and 70% of adult patients with ALL. The aim of this study was to determine the prevalence of these chromosomal abnormalities in ALL patients using Fluorescence in situ Hybridization (FISH) technique and to define the frequency of chromosomal abnormalities of ALL patients in adults and children in Erbil Province. Methods: In this cross-sectional study, we evaluated karyotype results in blood samples, that collected from 55 patients with ALL (in both sexes) in Nanakaly Hospital in Erbil Province. Thirty healthy individuals were selected as the control group. Patients ages ranged between 1 to 63 years old. The samples were centrifuged to extract nucleated cells. The cells were then subjected to hypotonic shock, fixed with methanol and acetic acid. A cell suspension was then prepared for FISH technique. After examining the samples with fluorescent microscope, the obtained data along with demographic and baseline characteristics of patients were entered in SPSS software, then statistically analyzed. Results: The prevalence of chromosomal abnormalities among ALL group was 52.7% (n = 29). Of these, 31¬% (9 people) had abnormalities in chromosome number and 69¬% (20 people) had abnormalities in chromosome structure. The most common chromosomal abnormality was translocation t (9; 22), which accounted for 31¬% of all abnormalities and its prevalence among ALL patients was 16.4¬%. Clonal trisomy and t (12; 21) also accounted for 13.8% and 10.3% of abnormalities, respectively. Clonal trisomy was the most common abnormality in chromosome number, accounting for 44.4% (n = 4) of abnormalities. Only one patient with single chromosome X (X0) pattern was observed in patients. There was no significant (P&gt; 0.05) relationship between the incidence of chromosomal abnormalities with gender, family history, history of surgery and bacterial infection, occupation, place of residence, smoking and blood type as stated from the questionnaire form. Conclusion In the current study, concluded that at least one chromosomal abnormality was found in more than half of all patients with ALL. Structural abnormalities were more common than chromosome number abnormalities. Normal karyotype was more frequent in this current study. The frequencies of some cytogenetic abnormalities such as hyperdiploidy and t (9;22) in the current study findings were comparable to those reported in the literature. The results of this study in Erbil Province can be used as baseline information for treatment decision and research purposes in ALL patients. We recommend the use of advanced molecular techniques in the future to better elucidate cryptic cytogenetic abnormalities.

The Relationship between Prenatal Diagnosis Indications and Abnormal Chromosomal Karyotypes: A Retrospective Cohort of 4646 Cases in Beijing from 2012-2019.

Chromosomal abnormalities are one of the genetic disorders caused by abnormal chromosome number or structure and can endanger multiple organs, morphology and function of the systems in the human body. This study aims to investigate the relationship between prenatal diagnosis indications and abnormal karyotypes to improve prenatal screening. The karyotype analyses were carried out on 4646 pregnant women with prenatal diagnosis indications referred to the first medical center of Chinese PLA General Hospital from 2012 to 2019. The incidence, distribution, and statistical features of chromosomal abnormality of different prenatal diagnosis indications were analyzed, and the relationships with the prenatal diagnosis indications were assessed. A total of 351 fetal chromosomal abnormalities were detected in 4646 karyotypes, with an incidence of 7.6%. The chromosomal abnormality incidence in the single indication group, two indications group, and three indications group was 5.8%, 16.1%, and 70.0%, respectively, indicating a statistically significant difference (p < 0.05). Advanced maternal age (AMA), high-risk maternal serum screening (MSS), and non-invasive prenatal DNA testing (NIPT) were the important indications for predicting abnormal karyotype. The number of prenatal diagnosis indications was highly correlated with fetal chromosomal abnormalities. The overall incidence of chromosomal abnormalities showed a tendency to increase with age. The incidence of Trisomy 21 was 3.2%, accounting for 42.5% of all chromosomal abnormalities, and the incidence tended to increase with maternal age. Prenatal karyotype analysis of pregnant women with prenatal diagnosis indications can effectively prevent the birth of defective children. AMA, MSS and NIPT were the important indications for predicting abnormal karyotype. In addition, the number of prenatal diagnosis indications is highly correlated with chromosomal abnormalities.