Fetal Chromosomal Abnormalities Research Articles

Analysis of copy number variations and possible candidate genes in spontaneous abortion by copy number variation sequencing.

Embryonic chromosomal abnormalities represent a major causative factor in early pregnancy loss, highlighting the importance of understanding their role in spontaneous abortion. This study investigates the potential correlation between chromosomal abnormalities and spontaneous abortion using copy number variation sequencing (CNV-seq), a Next-Generation Sequencing (NGS) technology. We analyzed Copy Number Variations (CNVs) in 395 aborted fetal specimens from spontaneous abortion patients by CNV-seq. And collected correlated data, including maternal age, gestational week, and Body Mass Index (BMI), and analyzed their relationship with the CNVs. Out of the 395 cases, 67.09% of the fetuses had chromosomal abnormalities, including numerical abnormalities, structural abnormalities, and mosaicisms. Maternal age was found to be an important risk factor for fetal chromosomal abnormalities, with the proportion of autosomal trisomy in abnormal karyotypes increasing with maternal age, while polyploidy decreased. The proportion of abnormal karyotypes with mosaic decreased as gestational age increased, while the frequency of polyploidy and sex chromosome monosomy increased. Gene enrichment analysis identified potential miscarriage candidate genes and functions, as well as pathogenic genes and pathways associated with unexplained miscarriage among women aged below or over 35 years old. Based on our study, it can be inferred that there is an association between BMI values and the risk of recurrent miscarriage caused by chromosomal abnormalities. Overall, these findings provide important insights into the understanding of spontaneous abortion and have implications for the development of personalized interventions for patients with abnormal karyotypes.

Prenatal cfDNA Screening for Emanuel Syndrome and Other Unbalanced Products of Conception in Carriers of the Recurrent Balanced Translocation t(11;22): One Laboratory's Retrospective Experience.

Prenatal cell-free DNA screening (cfDNA) can identify fetal chromosome abnormalities beyond common trisomies. Emanuel syndrome (ES), caused by an unbalanced translocation between chromosomes 11 and 22, has lacked a reliable prenatal screening option for families with a carrier parent. A cohort of cases (n = 46) sent for cfDNA screening with indications and/or results related to ES was queried; diagnostic testing and pregnancy outcomes were requested and analyzed. No discordant results were reported or suspected; there were ten true positives with diagnostic confirmation, six likely concordant positives based on known translocations and consistent cfDNA data, and twenty-six true negatives, by diagnostic testing or birth outcomes. For cases with parental testing, all affected ES cases had maternal translocation carriers. Expanded cfDNA may provide reassurance for t(11;22) carriers with screen negative results, and screen positive results appear to reflect a likely affected fetus, especially with a known maternal translocation. Current society guidelines support the use of expanded cfDNA screening in specific circumstances, such as for translocation carriers, with appropriate counseling. Diagnostic testing is recommended for prenatal diagnosis of ES and other chromosome abnormalities in pregnancy. To our knowledge, this cohort is the largest published group of cases with prenatal screening for carriers of t(11;22).

The value of non-invasive prenatal testing for the identification of numerical and structural chromosomal abnormalities and copy number variations in the fetuses

To assess the value of non-invasive prenatal testing (NIPT) for the identification of numerical and structural chromosomal abnormalities and copy number variations (CNVs) in fetuses. 46 197 pregnant women undergoing NIPT at the Prenatal Diagnosis Center of Chenzhou First People's Hospital from January 2018 to December 2021 were selected as the study subjects. Positive cases were subjected to chromosomal karyotyping and copy number variation sequencing (CNV-seq) following amniocentesis. Nearly 50% of common chromosomal aneuploidies were found in the elder pregnant women. Among these, sex chromosome aneuploidies were mainly found in pregnant women with advanced age as well as borderline risks by serological screening. Rare autosomal aneuploidies and CNVs were mainly found in those with borderline or high risks by serological screening. The positive predictive values (PPV) for fetal chromosomal abnormalities indicated by NIPT were as follows: T21 (92.37%, 109/118), T18 (53.85%, 14/26), sex chromosome aneuploidies (45.04%, 59/131), T13 (34.62%, 9/26), CNVs (29.17%, 14/48), and rare autosomal aneuploidies (2.60%, 2/77). NIPT has a high detection rate for T21, T18, T13 and sex chromosome aneuploidies. It can also detect rare autosomal aneuploidies and CNVs, including some rare structural abnormalities, though verification is required by analyzing amniotic fluid samples.

Association of chromosomal abnormalities with prenatal exposure to heavy metals: A nested case-control study in high-risk pregnant women in China

Prenatal exposure to heavy metals causes multiple hazards to fetal growth and development. Epidemiological studies on the association between heavy metals and fetal chromosomal abnormalities (CAs) are lacking. We conducted a nested case-control study in a cohort of high-risk pregnant women in China from September 2018 to June 2021. A total of 387 participants were diagnosed with fetal CAs in the case group and 699 were diagnosed with a normal karyotype in the control group. Amniotic fluid concentrations of 10 metals (barium, cobalt, antimony, manganese, ferrum, copper, selenium, strontium, vanadium, and chromium) were measured using inductively coupled plasma-mass spectrometry. We applied quantile g-computation and weighted quantile sum regression to assess the overall effect of metal mixtures and identify metals with significant weight. Logistic and Poisson regression analyses were used to estimate the effects of metals on CAs and CAs subtypes. Our results showed that the metal mixture concentrations were positively associated with the risk of fetal CAs. In adjusted logistic models, Sb was associated with fetal CAs (OR=1.15, 95% CI: 1.02–1.30), and revealed a linear dose-response relationship between Sb level and the risk of fetal CAs. Additionally, the exploratory analysis revealed that Sb levels were associated with Klinefelter syndrome (OR=1.452, 95% CI: 1.063–1.984) and Turner syndrome (OR=1.698; 95% CI,1.048–2.751). Our study revealed that metal mixtures are associated with a higher risk of fetal CAs and that this association may be driven primarily by Sb. Moreover, we provide a genetic perspective on the effects of heavy metals on sexual development in humans.

NOD-like receptors in pathogenesis of missed and spontaneous abortions

Nucleotide-binding oligomerization domain-like receptors (NOD-like receptors) are cytosolic signaling receptors of innate immune cells recognizing ligands derived from bacteria, viruses, fungi and protozoa. They can initiate apoptosis and pro-inflammatory cytokines production. Meanwhile, the role of decidual NOD-like receptors in pathogenesis of early miscarriages remains unknown. Aim: to study NOD-like receptor (NOD1, NOD2, NLRP1, NLRP3, NLRC4) messenger ribonucleic acid (mRNA) expression in decidual tissue from patients with missedand spontaneous abortions compared to progressive pregnancy.Materials and Methods. NOD1, NOD2, NLRP1, NLRP3, NLRC4 and pathway protein receptorinteracting-serine/threonine-protein kinase 2 (RIP-2) mRNA expression in decidua from 34 patients with missed abortions (group I), 34 patients with spontaneous abortions (group II) and 57 women with progressive pregnancy admitted for artificial abortion (group III, control group) were analyzed by reverse transcription quantitative polymerase chain reaction (PCR) at gestational age of 6–10 weeks. Exclusion criteria were as follows: endocrine disorders, severe extragenital diseases, antiphospholipid syndrome, inherited thrombophilia, uterine malformations and fetal chromosomal abnormalities. Samples were collected by uterine abrasion. Results. It was found that mRNA expression of NOD2 was significantly higher in decidua from patients with missed and spontaneous abortions, whereas for RIP-2 (related to relevant signaling pathway) – in women with missed abortions. A moderate positive correlation between gestational age and mRNA expression for NOD2 (R = 0.48; p = 0.01) and RIP-2 (R = 0.41; p = 0.007) was observed in subjects with progressive pregnancy. In contrast, women with missed abortions showed a moderate negative correlation between body weight and mRNA expression for NOD2 (R = –0.46; p = 0.03) and RIP-2 (R = –0.51; p = 0.02) whereas spontaneous abortions was associated with moderate negative correlation between RIP-2 mRNA expression and body weight (R= –0.47; p=0.04) as well as body mass index (R= –0.48; p = 0.04) along with moderate positive correlation with age of menarche (R = 0.46; p = 0.04). However, compared with progressive pregnancy no significant differences were found in expression level form NOD1, NLRP1, NLRP3 and NLRC4 mRNA in decidua from patients with missed and spontaneous abortions. Conclusion. Elevated NOD2 mRNA expression was observed in decidua from patients with missed and spontaneous abortions compared to progressive pregnancy paralleled with upregulated RIP-2 mRNA expression in missed abortions. Finally, it was found that NOD1, NLRP1, NLRP3 and NLRC4 were not involved in pathogenesis of miscarriages.

Can uterine artery pulsatility index predict fetal chromosomal abnormality in early pregnancy loss? A retrospective cohort study.

Early pregnancy loss (EPL) or spontaneous loss of an intrauterine pregnancy within the first trimester occurs commonly worldwide. It is useful to predict the possibility of fetal chromosomal abnormalities using other cheap and easily available markers. This study aimed to evaluate whether the uterine artery pulsatility index (UtA-PI) can predict fetal chromosomal abnormality in early pregnancy loss (EPL). This was a retrospective cohort study including 148 women who underwent dilation and curettage for missed abortion. The UtA-PI was measured and evaluated by transvaginal ultrasound. Abnormal UtA-PI was identified through the mean of left and right UA-PI ≥ 90th percentiles of the relevant values for the corresponding gestational age. Copy number variation sequencing (CNV-seq) was performed on EPL cases without maternal cell contamination. 107 (72.3%) cases were classified with normal UtA-PI, while 41 (27.7%) cases were classified with abnormal UtA-PI. The fetal chromosomal abnormality rate was significantly higher in cases with normal UtA-PI than in those with abnormal UtA-PI (67.3% vs 22.0%, P = 7.1 × 10-7). Compared to cases with abnormal UtA-PI, the risk of fetal chromosomal abnormalities in cases with normal UtA-PI increased with an odds ratio of 7.3 (95% confidence interval [CI]: 3.2‒17.0, P = 4 × 10-7). The predictive value of normal UtA-PI alone for fetal chromosomal abnormalities was shown to have an area under the curve of 0.67‒0.71 in our population. The UtA-PI seems to be lower and less likely to be elevated in EPL with fetal chromosomal abnormalities compared to those without aneuploidies. We suggest that UtA-PI should be examined in all EPL patients.

Pregnancy, delivery, and neonatal outcomes among women living with Down syndrome: a matched cohort study, utilizing a population database.

We utilized a population database to address the paucity of data around pregnancy outcomes in women with Down syndrome (DS). We conducted a retrospective study using the Health Care Cost and Utilization Project-Nationwide Inpatient Sample Database over 11years, from 2004 to 2014. A delivery cohort was created using ICD-9 codes. ICD-9 code 758.0 was used to extract the cases of maternal DS. Pregnant women with DS (study group) were matched based on age, race, income, and health insurance type to women without DS (control) at a ratio of 1:20. There were a total of 9,096,788 deliveries during the study period. Of those, 184 pregnant women were found to have DS. The matched control group was 3680. After matching, most of the pregnancy and delivery outcomes, such as pregnancy-induced hypertension, gestational diabetes, preterm premature rupture of membrane, chorioamnionitis, cesarean section, operative vaginal delivery, or blood transfusion were similar between participants with and without DS. However, patients with DS were at increased risk of giving birth prematurely (aOR 3.09, 95% CI 2.06-4.62), and having adverse neonatal outcomes such as small for gestational age (aOR 2.70, 95% CI 1.54-4.73), intrauterine fetal demise (aOR 22.45, 95% CI 12.02-41.93), congenital anomalies (aOR 7.92, 95% CI 4.11-15.24), and fetal chromosomal abnormalities. Neonates to mothers with DS are at increased risk of prematurity and other neonatal adverse outcomes. Hence, counseling patients with DS about these risks and increased antenatal surveillance is advised.

The effectiveness of non-invasive prenatal test technology and the prenatal screening algorithm based on various methods for determining foetal aneuploidy.

The purpose was to evaluate the effectiveness of a non-invasive prenatal test (NIPT) using mass parallel sequencing (MPS) to detect trisomy 13, 18, 21 and fetal sex chromosome abnormalities in maternal blood samples by isolating freely circulating foetal extracellular DNA (eDNA), and to develop an algorithm for prenatal screening. The research methods used included blood sampling from patients, isolation of eDNA, determination of DNA concentration and quality, library preparation for sequencing, MPS using an Illumina HiSeq2000, positive and negative control samples, monitoring, and analysis of results using the distributed algorithms platform based on calculations of z-value and the average absolute deviation. Pregnant women were divided into two groups based on gestational age at sampling, group 1; 9-14 weeks and group 2; 15-27 weeks. A total of 377 pregnant women were included with a mean (range) age of 33 (23-44) years. The mean gestational age at the time of blood sampling in group 1 was 11 (9-14) weeks, and in group 2 was 21 (15-27) weeks. In the first group, three cases of trisomy 18 chromosomes were detected in patients aged 43 years old, and female children were subsequently born with Edwards syndrome. In the second group, one case of trisomy 21 was detected in a patient aged 36 years and the pregnancy was terminated at 25 weeks. The analysis of freely circulating foetal eDNA was a sensitive method for detecting chromosomal abnormalities. The study has a practical significance, since the NIPT for frequent aneuploidy considerably exceeds the effectiveness of traditional screening methods and allows identifying chromosomal disorders starting from the 9th week of the gestation period.

CHALLENGES FOR CHROMOSOME ANALYSIS IN PREGNANCY LOSS: LESSONS LEARNED FROM 1208 SAMPLE EXPERIENCE

Objective: Previous studies have shown that half of the spontaneous abortions were associated with fetal chromosomal abnormalities, however it is not always possible to reveal the reasons of pregnancy loss. The aim of the current study was to investigate the frequency of chromosome abnormalities and culture failure rates of pregnancy loss and compare the results with similar studies in the literature.
 
 Material and Methods: The karyotype analysis results of 1208 abortion materials which were obtained from long-term cultures of chorionic villus samples of the patients who were admitted to the Haseki Training and Research Hospital Genetic Diagnosis Center between August 2016 and February 2021, were evaluated retrospectively.
 
 Results: No results were obtained due to culture failure in approximately half of the materials. Numerical anomalies were observed in 87% (116) of abnormal karyotypes that consist of trisomy, monosomy X and triploidy. Trisomies were the most common anomaly. While the frequency of trisomy was significantly higher in the older age group (≥35 years) (p=0.001), the frequency of monosomy X and triploidy were higher in the younger age group. Chromosomal changes whose frequencies were not affected by maternal age were structural chromosomal abnormalities and tetraploidies.
 
 Conclusion: Since the developing new Technologies are still not affordable enough and their widespread use is limited. As a result, current approaches have indicated that chromosome analysis is still a necessary and useful method. It is thought that detecting the chromosomal anomaly that led to abortion facilitates multidisciplinary patient management and enables to provide more accurate and comprehensive genetic counseling. In cases where the chromosome analysis test is not informative, the application of DNA-based tests such as Quantitative Fluorescence PCR (QF-PCR) and molecular karyotyping may help the diagnosis.

Defining the scope of extended NIPS in Western China: evidence from a large cohort of fetuses with normal ultrasound scans

BackgroundStandard noninvasive prenatal screening(NIPS) is an accurate and reliable method to screen for common chromosome aneuploidies, such as trisomy 21, 18 and 13. Extended NIPS has been used in clinic for not only aneuploidies but also copy number variants(CNVs). Here we aim to define the range of chromosomal abnormalities that should be able to identify by NIPS in order to be an efficient extended screening test for chromosomal abnormalities.MethodsA prospective study was conducted, involving pregnant women without fetal sonographic structural abnormalities who underwent amniocentesis. Prenatal samples were analyzed using copy number variation sequencing(CNV-seq) to identify fetal chromosomal abnormalities.ResultsOf 28,469 pregnancies included 1,022 (3.59%) were identified with clinically significant fetal chromosome abnormalities, including 587 aneuploidies (2.06%) and 435 (1.53%) pathogenic (P) / likely pathogenic (LP) CNVs. P/LP CNVs were found in all chromosomes, but the distribution was not uniform. Among them, P/LP CNVs in chromosomes 16, 22, and X exhibited the highest frequencies. In addition, P/LP CNVs were most common on distal ends of the chromosomes and in low copy repeat regions. Recurrent microdeletion/microduplication syndromes (MMS) accounted for 40.69% of total P/LP CNVs. The size of most P/LP CNVs (77.47%) was < 3 Mb.ConclusionsIn addition to aneuploidies, the scope of extended NIPS should include the currently known P/LP CNVs, especially the regions with recurrent MMS loci, distal ends of the chromosomes, and low copy repeat regions. To be effective detection should include CNVs of < 3 Mb. Meanwhile, sufficient preclinical validation is still needed to ensure the clinical effect of extended NIPS.

Retrospective analysis of cell-free fetal DNA prenatal testing of maternal peripheral blood

To assess the value of non-invasive prenatal testing (NIPT) for trisomy 21 (T21), trisomy 18 (T18), trisomy 13 (T13), sex chromosome aneuploidies, chromosomal microdeletions and microduplications using cell-free fetal DNA from peripheral blood samples of pregnant women. A total of 15 237 pregnant women who had undergone NIPT testing at the Maternity and Child Health Care Hospital of Zaozhuang from February 2015 to December 2021 were enrolled in this study. For those with a high risk by NIPT, amniotic fluid samples were collected for G-banding chromosomal karyotyping analysis and chromosomal microarray analysis to verify the consistency of NIPT with results of prenatal diagnosis. All of the women were followed up by telephone for pregnancy outcomes. Among the 15 237 pregnant women, 266 (1.75%) were detected with a high risk for fetal chromosomal abnormality were detected. Among these, 79 (29.7%) were at a high risk for T21, 26 (9.77%) were at a high risk for T18, 9 (3.38%) were at a high risk for T13, 74 (27.82%) were at a high risk for sex chromosome aneuploidies, 12 (4.51%) were at a high risk for other autosomal aneuploidies, and 66 (24.81%) were at a high risk for chromosomal microdeletions or microduplications. 217 women had accepted invasive prenatal diagnosis and respectively 50, 13, 1, 25, 1 and 18 were confirmed with T21, T18, T13, sex chromosome aneuploidies, autosomal aneuploidies and microdeletions/microduplications, and the positive predictive values were 75.76%, 68.42%, 11.11%, 40.32%, 10% and 35.29%, respectively. For 13 042 women (85.59%), the outcome of pregnancy were successfully followed up. During the follow-up, one false negative case of T21 was discovered. No false positive cases for T13 and T18 were found. NIPT has a sound performance for screening T13, T18 and T21, and is also valuable for screening other autosomal aneuploidies, sex chromosome aneuploidies and chromosomal microdeletions/microduplications.

A Novel Paradigm for Non-Invasive Prenatal Genetic Screening: Trophoblast Retrieval and Isolation from the Cervix (TRIC).

As the prevalence of pregnancies with advanced maternal age increases, the risk of fetal chromosomal abnormalities is on the rise. Therefore, prenatal genetic screening and diagnosis have become essential elements in contemporary obstetrical care. Trophoblast retrieval and isolation from the cervix (TRIC) is a non-invasive procedure that can be utilized for prenatal genetic diagnosis. The method involves the isolation of fetal cells (extravillous trophoblasts) by transcervical sampling; along with its non-invasiveness, TRIC exhibits many other advantages such as its usefulness in early pregnancy at 5 weeks of gestation, and no interference by various fetal and maternal factors. Moreover, the trophoblast yields from TRIC can provide valuable information about obstetrical complications related to abnormal placentation even before clinical symptoms arise. The standardization of this clinical tool is still under investigation, and the upcoming advancements in TRIC are expected to meet the increasing need for a safe and accurate option for prenatal diagnosis.

Can we predict peritoneal adhesions formation after cesarean delivery?

To examine demographic and obstetrical factors that are associated with adhesion formation following cesarean delivery. We conducted a population-based study that included all women over 18 years og age who underwent two cesarean deliveries between the years 1988 and 2016 in a large tertiary medical center. We excluded women with adhesions already diagnosed during the first cesarean delivery, history of other abdominal or pelvic surgery, history of pelvic infection or pelvic inflammatory disease, history of endometriosis and history of uterine Müllerian anomalies. In addition, women with a classical or T-shaped uterine incision, non-singleton pregnancies, and fetal chromosomal or structural abnormalities were excluded. During the study period, 32.6% (n = 2283) of women were diagnosed with peritoneal adhesions during the second cesarean delivery. Factors found to be significantly associated with peritoneal adhesions were maternal age 35 years or older at the first cesarean delivery, Bedouin Arab ethnicity, composite of intrapartum and postpartum infectious morbidity, and cesarean deliveries that were performed after the onset of labor. In contrast, having a previous vaginal birth was found to be protective. Our results suggest that a woman's characteristics at her first cesarean delivery and her obstetrical history may be predictive of the likelihood of adhesion formation.

The relationship of maternal polymorphisms of genes related to meiosis and DNA damage repair with fetal chromosomal stability.

To evaluate the association between maternal polymorphisms of NANOS3 rs2016163, HELQ rs4693089, PRIM1 rs2277339, TLK1 rs10183486, ERCC6 rs2228526, EXO1 rs1635501, DMC1 rs5757133, and MSH5 rs2075789 and fetal chromosomal abnormality. This retrospective case-control study included 571 women with fetal chromosome abnormalities (330 pregnant women diagnosed with fetal aneuploidy, 241 with fetal de novo structural chromosome pregnancy) and 811 healthy pregnant women between January 2018 and April 2022. All the above polymorphisms were tested using SNaPshot. All the eight polymorphisms were analyzed for genotypes, alleles, under dominant and recessive genetic models. Significant distribution differences of TLK1 rs10183486 in fetal chromosome structural abnormality were found between the case group and control subjects who were<35 years of age [Genotype: p=0.029; Dominant: OR (95 %CI)=0.46 (0.25-0.82), p=0.01 and allele: OR (95 %CI)=0.47 (0.27-0.82), p=0.01 respectively], while no difference was found in the recessive model [OR (95 %CI)=2.49 (0.31-20.40), p=0.39]. In advanced age subgroups for fetal aneuploidy, significant differences were found in genotypes analysis of PRIM1 rs2277339 (p=0.008), allele analysis of TLK1 rs10183486 [OR (95 %CI)=0.62 (0.42-0.91), p=0.02]. For thefetal chromosome structural abnormality population, HELQ rs4693089 revealed a significant distribution difference (p=0.01) but not in the allele, dominant and recessive genetic models analysis (p>0.05 individually). For older women, maternal PRIM1 rs2277339 and TLK1 rs10183486 polymorphisms may be associated with fetal aneuploidy, while HELQ rs4693089 may be associated with fetal chromosome structural abnormality. Also, carriers of T allele of TLK1 rs10183486 have a lower risk of fetal chromosome structural abnormality in younger women.

Overview of Noninvasive Prenatal Testing (NIPT) for the Detection of Fetal Chromosome Abnormalities; Differences in Laboratory Methods and Scope of Testing.

Although nearly all noninvasive prenatal testing is currently based on analyzing circulating maternal cell-free DNA, the technical methods usedvary considerably. We review the different methods. Based on validation trials and clinical experience, there are mostly relatively small differences in screening performance for trisomies 21, 18, and 13 in singleton pregnancies. Recent reports show low no-call rates for all methods, diminishing its importance when choosing a laboratory. However, method can be an important consideration for twin pregnancies, screening for sex chromosome abnormalities, microdeletion syndromes, triploidy, molar pregnancies, rare autosomal trisomies, and segmental imbalances, and detecting maternal chromosome abnormalities.

The impact of early diagnosis of fetal single-ventricle cardiac defects on reproductive choices

Congenital heart defects are the most common fetal anomaly. Congenital heart defects with single ventricle cardiac defects have high mortality rates, and in pregnancies diagnosed with this condition, patients are often offered termination of pregnancy (TOP) as an option. This study aimed to investigate the relationship between gestational age at diagnosis and reproductive choices in fetuses diagnosed with single ventricle cardiac defects. We conducted a retrospective single-center cohort study in which 158 patients with a fetal diagnosis of single ventricle cardiac defects (SVCD) were reviewed. Cases were categorized as isolated or complex. Complex cases included fetuses with SVCD in addition to other fetal extracardiac anomalies (ECA) or chromosomal abnormalities. 158 patients were diagnosed with SVCDs during the study period. Of those, 37 (23.4%) underwent termination of pregnancy, 113 (71.5%) delivered, and 8 (5.1%) had an intrauterine fetal demise. Gestational age at diagnosis and race were significant predictors of the termination decision. The median gestational age at diagnosis was earlier in the TOP group (20.4 vs. 23.6 weeks) (p < 0.001). SVCD diagnosed in early gestation (11 weeks-14 weeks 5 days) were more likely to terminate compared to Mid (15 weeks-27 weeks 5 days) and late (28+ weeks) gestation (54.2 % vs 23.2% and 2.9%) (p<0.001). Earlier gestational age at diagnosis was correlated with earlier gestational age at termination (r= 0.92, p < 0.001). Termination of pregnancy is more common when the SVCD is diagnosed earlier in gestation. This could be explained by the fact that early diagnoses allow parents to make deliberate and informed decisions.

Fetal congenital gastrointestinal obstruction: prenatal diagnosis of chromosome microarray analysis and pregnancy outcomes

ObjectiveThe aim of this study was to investigate the incidence of chromosome anomalies in different types of congenital gastrointestinal obstruction and assess pregnancy outcomes of fetuses with congenital gastrointestinal obstruction.MethodsA total of 64 cases with gastrointestinal obstruction between January 2014 and December 2020 were enrolled in this study. They were divided into three groups according to sonographic images. Group A: isolated upper gastrointestinal obstruction; Group B: isolated lower gastrointestinal obstruction; Group C: non-isolated gastrointestinal obstruction. The rate of chromosome anomalies in different groups was calculated. Pregnant women with amniocentesis were followed up by medical records and telephone. The follow-up included pregnancy outcomes and development of the live born infants.ResultFrom January 2014 to December 2020, there were 64 fetus with congenital gastrointestinal obstruction underwent chromosome microarray analysis(CMA), the overall detection rate of CMA testing was 14.1%(9/64). The detection rate of Group A, B and C were 16.2%, 0 and 25.0% respectively. 9 fetuses with abnormal CMA results were all terminated. Among 55 fetuses with normal chromosomes, 10(18.2%) fetuses were not found to have any gastrointestinal obstruction after birth. 17(30.9%) fetuses were diagnosed with gastrointestinal obstruction and underwent surgical treatment after birth, one of which had lower gastrointestinal obstruction combined with biliary obstruction and died due to liver cirrhosis. 11(20.0%) pregnancy were terminated due to multiple abnormalities. 5(9.1%) fetuses were intrauterine death. 3(5.5%) fetuses were neonatal deaths. 9(16.4%) fetuses were lost to follow-up.ConclusionIt is crucial to understand whether the gastrointestinal tract abnormality is isolated or associated to other findings. The risk of chromosomal abnormalities in fetuses with isolated lower gastrointestinal obstruction is lower than upper gastrointestinal obstruction. While genetic abnormalities excluded, a promising prognosis is expected for fetuses with congenital gastrointestinal obstruction.

Analysis of Fetal Chromosome Abnormalities by Karyotpye

Prenatal screening is a crucial method employed during the fetal stage to detect and intervene early, thereby ensuring the health of newborn babies. This approach serves to enhance the overall quality of the population and mitigate the severe consequences associated with birth defects. Prenatal screening encompasses various techniques, including epidemiological investigations, fetal imaging ultrasound, maternal blood screening, and amniotic fluid screening by karotype technique. The process involves extracting fetal chromosomes from cells present in the amniotic fluid, followed by cell culture and hypotonic treatment. Subsequently, these chromosomes are stained with G-band and examined under a microscope. The results obtained from prenatal screening in a sample of 121 patients, with an average age of 32 ± 6.69, indicated that 21% of pregnant women had experienced a miscarriage, 23.1% had previously given birth to a malformed baby, 8.3% of families had a genetic disease, and 5% of parents exhibited chromosomal abnormalities. Among the 51 patients screened using the Double test, 26.45% of fetuses exhibited a high risk of birth defects, whereas the Tripple test identified a high risk in 9.09% of the 19 cases. Chromosome analysis of the 121 cases revealed that 15.7% of the fetuses exhibited chromosomal abnormalities, with Edwards syndrome accounting for 5.78%, Down syndrome accounting for 4.96%, chromosomal abnormalities accounting for 3.30%, Patau syndrome accounting for 0.83%, and Turner syndrome accounting for 0.83%. Age over 35 years (r = 0.08 and OR = 0.63), history of miscarriage (r = 0.05 and OR = 1.38), family history of hereditary disease (r = 0.04 and OR = 1.38), and parental chromosomal mutations (r = 0.01 and OR = 1.08) were all found to have a strong positive correlation with fetal abnormalities. Additionally, positive correlations were observed between the results of ultrasound screening (r = 0.22 and OR = 5.48) and blood screening (r = 0.14 and OR = 1.22).&#x0D; Prenatal screening, Amniocentesis, Karyotype, Chromosome, fetal chromosome.&#x0D; &#x0D; &#x0D;

Intra-abdominal umbilical venous diameter and abdominal circumference discordance at 15-20weeks' gestation: simple markers in transverse abdominal plane to predict adverse pregnancy outcomes in monochorionic diamniotic twins.

This study aimed to investigate the association between simple markers in fetal abdominal plane, intra-abdominal umbilical venous diameter (DIUV) and abdominal circumference (AC) discordance at 15-20weeks' gestation, and adverse pregnancy outcomes in monochorionic diamniotic (MCDA) twins. We performed a retrospective analysis of MCDA twins with two live fetuses examined at 15-20weeks from Jun 2020 to Dec 2021 at Beijing Obstetrics and Gynecology Hospital. Measurement of fetal AC and DIUV was performed according to standard protocols. Twin pregnancies with major fetal structural anomalies, chromosomal abnormalities, miscarriage, and twin reversed arterial perfusion sequence were excluded. DIUV and AC discordance in MCDA twins with an adverse pregnancy outcome was compared with a normal pregnancy outcome. Furthermore, the performance of DIUV and AC discordance in predicting adverse pregnancy outcomes in MCDA twins was assessed. A total of 105 women with MCDA twin pregnancies were enrolled, contributing 179 visits. Adverse pregnancy outcomes occurred in 33.3% (35/105) of cases in our study. The intra-observer and inter-observer intraclass correlation coefficient (ICC) of both AC and DIUV were very good or excellent. There was no statistical difference in AC and DIUV discordance (%) between 15-16, 17-18, and 19-20weeks (χ2 = 3.928, P = 0.140; χ2 = 2.840, P = 0.242). Both AC and DIUV discordance were greater in twins with adverse pregnancy outcomes than that in twins with normal pregnancy outcome at each pregnancy periods. Both AC discordance (OR 1.2, 95% CI 1.1-1.3) and DIUV discordance (OR 1.2, 95% CI 1.1-1.2) were associated with adverse pregnancy outcomes. The AUC for predicting adverse pregnancy outcomes by AC discordance was 0.75 (95% CI 0.68-0.83), with a sensitivity of 58.7% (95% CI 51.9-64.5) and a specificity of 86.2% (95% CI 81.7-88.4). The AUC for predicting adverse pregnancy outcomes by DIUV was 0.78 (95% CI 0.70-0.86), with sensitivity and specificity of 65.1% (95% CI 58.1-70.3) and 86.2% (95% CI 81.7-88.4), respectively. The AC discordance and DIUV discordance could predict adverse pregnancy outcomes in MCDA twins. When these simple markers occurred, intensive surveillance was recommended.

Clinical and genetic analysis of a fetus with 17q12 microdeletion syndrome

To explore the clinical phenotype and genetic characteristics of a fetus with 17q12 microdeletion syndrome. A fetus with 17q12 microdeletion syndrome who was diagnosed at Huzhou Maternal & Child Health Care Hospital in June 2020 was selected as the study subject. Clinical data of the fetus was collected. The fetus was subjected to chromosomal karyotyping and chromosomal microarray analysis (CMA). To determine the origin of fetal chromosomal abnormality, its parents were also subjected to CMA assay. The postnatal phenotype of the fetus was also investigated. Prenatal ultrasound revealed polyhydramnios and fetal renal dysplasia. The fetus was found to have a normal chromosomal karyotype. CMA has detected a 1.9 Mb deletion in the 17q12 region, which has encompassed five OMIM genes including HNF1B, ACACA, ZNHIT3, CCL3L1 and PIGW. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the 17q12 microdeletion was predicted as pathogenic copy number variation (CNV). CMA analysis has detected no pathogenic CNV in both parents. After birth, the child was found to have renal cysts and abnormal brain structure. Combined with the prenatal findings, the child was diagnosed with 17q12 microdeletion syndrome. The fetus has 17q12 microdeletion syndrome presenting as abnormalities of the kidney and central nervous system, which are strongly correlated with functional defects of the deletion region involving the HNF1B and other pathogenic genes.