OBJECTIVE: To explore the genetic etiology and related factors in 1 065 women with spontaneous abortions. METHODS: All patients have presented at the Center of Prenatal Diagnosis of Nanjing Drum Tower Hospital from January 2018 to December 2021. Chorionic villi and fetal skin samples were collected, and the genomic DNA was assayed by chromosomal microarray analysis (CMA). For 10 couples with recurrent spontaneous abortions but normal CMA results for abortive tissues, non-in vitro fertilization-embryo transfer (IVF-ET) pregnancies and no previous history of live births and no structural abnormalities of the uterus, peripheral venous blood samples were collected. Genomic DNA was subjected to trio-whole exome sequencing (trio-WES). Candidate variants were verified by Sanger sequencing and bioinformatics analysis. Multifactorial unconditional logistic regression analysis was carried out to analyze the factors that may affect chromosomal abnormality in spontaneous abortions, such as the age of the couple, number of previous spontaneous abortions, IVF-ET pregnancy and history of live birth. The incidence of chromosomal aneuploidies in spontaneous abortions during the first trimester was compared in young or advanced-aged patients by chi-square test for liner trend. RESULTS: Among the 1 065 spontaneous abortion patients, 570 cases (53.5%) of chromosomal abnormalities were detected in spontaneous abortion tissues, which included 489 cases (45.9%) of chromosomal aneuploidies and 36 cases (3.4%) of pathogenic/likely pathogenic copy number variations (CNVs). Trio-WES results have revealed one homozygote variant and one compound heterozygote variants in two pedigrees, both of which were inherited from the parents. One likely pathogenic variant was detected in the patient from two pedigrees. Multifactorial unconditional Logistic regression analysis suggested that age of patient was an independent risk factor of chromosome abnormalities (OR = 1.122, 95%CI: 1.069-1.177, P < 0.001), the number of previous abortions and IVF-ET pregnancy were independent protective factors for chromosomal abnormalities (OR = 0.791, 0.648; 95%CI: 0.682-0.916, 0.500-0.840; P = 0.002, 0.001), whilst the age of husband and history of live birth were not (P > 0.05). The incidence of aneuploidies in the abortive tissues has decreased with the number of previous spontaneous abortions in young patients (χ² = 18.051, P < 0.001), but was not significantly correlated with the number of previous spontaneous abortions in advanced-aged patients with spontaneous abortions (P > 0.05). CONCLUSION Chromosomal aneuploidy is the main genetic factor for spontaneous abortion, though CNVs and genetic variants may also underlie its genetic etiology. The age of patients, number of previous abortions and IVF-ET pregnancy are closely associated with chromosome abnormalities in abortive tissues.
Pregnancy ; Humans ; Female ; Aged ; Abortion, Spontaneous/genetics* ; DNA Copy Number Variations ; Chromosome Aberrations ; Chromosome Disorders/genetics* ; Aneuploidy ; Abortion, Habitual/genetics*

BACKGROUNDGenetic factors are the main cause of early miscarriage. This study aimed to investigate aneuploidy in spontaneous abortion by fluorescence in situ hybridization (FISH) using probes for 13, 16, 18, 21, 22, X and Y chromosomes.

METHODSA total of 840 chorionic samples from spontaneous abortion were collected and examined by FISH. We analyzed the incidence and type of abnormal cases and sex ratio in the samples. We also analyzed the relationship between the rate of aneuploidy and parental age, the rate of aneuploidy between recurrent abortion and sporadic abortion, the difference in incidence of aneuploidy between samples from previous artificial abortion and those from no previous induced abortion.

RESULTSA total of 832 samples were finally analyzed. 368 (44.23%) were abnormal, in which 84.24% (310/368) were aneuploidies and 15.76% (58/368) were polyploidies. The first was trisomy 16 (121/310), followed by trisomy 22, and X monosomy. There was no significant difference in the rate of aneuploidy in the advanced maternal age group (≥ 35 years old) and young maternal age group (<35 years old). However, the rate of trisomy 22 and the total rate of trisomies 21, 13, and 18 (the number of trisomy 21 plus trisomy 13 and trisomy 18 together) showed significantly different in two groups. We found no skewed sex ratio. There was no significant difference in the rate of aneuploidy between recurrent miscarriage and sporadic abortion or between the samples from previous artificial abortion and those from no previous artificial abortion.

CONCLUSIONSAneuploidy is a principal factor of miscarriage and total parental age is a risk factor. There is no skewed sex ratio in spontaneous abortion. There is also no difference in the rate of aneuploidy between recurrent abortion and sporadic abortion or between previous artificial abortion and no previous induced abortion.

Abortion, Habitual ; genetics ; Abortion, Spontaneous ; genetics ; Adult ; Aneuploidy ; Female ; Humans ; In Situ Hybridization ; Middle Aged ; Pregnancy ; Sex Ratio

No abstract available.
Abortion, Induced* ; Abortion, Spontaneous/genetics* ; Adult ; Chromosome Aberrations/epidemiology* ; Chromosome Disorders ; Female ; Human ; Korea ; Pregnancy ; Pregnancy Trimester, First

OBJECTIVETo explore the relationship between spontaneous miscarriage and chromosomal aberrations identifiable with chromosomal microarray analysis (CMA).

METHODSA total of 440 product-of-conceptions were collected for the CMA testing.

RESULTSFour hundred and seventeen of 440 specimens (94.7%) were successfully detected, among which 209 (50.1%) were chromosomal abnormalities. One hundred and twenty-nine (61.7%) of the 209 specimens were numerical chromosomal abnormalities, 40 specimens (19.1%) were structural anomalies, 38 specimens (18.1%) were mosaicisms, and 2 specimens (1.0%) showed regions of homozygosity.

CONCLUSIONCMA analysis of products of-conception specimens can yield a higher diagnostic rate than conventional karyotyping. The identification of the cause of spontaneous miscarriage can facilitate estimation of recurrence risks for future pregnancies.

Abortion, Spontaneous ; etiology ; genetics ; Chromosome Aberrations ; Cohort Studies ; Female ; Humans ; Karyotyping ; Microarray Analysis ; methods ; Pregnancy

OBJECTIVE: To assess the value of chromosomal microarray analysis (CMA) and next-generation sequencing (NGS) for the analysis of abortic tissues. METHODS: A total of 242 samples of spontaneous abortion were collected and tested by CMA or NGS. RESULTS: The detection was successfully in 238 cases (98.35%). In total 143 cases of chromosomal abnormalities were detected, which accounted for 60.08% of all cases. Numerical chromosomal abnormalities were found in 133 cases(93.01%), structural abnormalities were found in 9 cases (6.29%), and uniparental disomy was found in 1 case(0.70%). CONCLUSION Both CMA and NGS have the advantages of high-throughput, good coverage, high resolution and rapid analysis. They can be used for the detection of the causes of spontaneous abortions. CMA is more useful for the detection of aneuploidies and uniparental disomy, while NGS has advantages in its throughput, capacity in detecting low percentage chimerism and cost, which can provide more options for clinicians.
Abortion, Spontaneous ; genetics ; Chromosome Aberrations ; Female ; High-Throughput Nucleotide Sequencing ; Humans ; Microarray Analysis ; Pregnancy

OBJECTIVE: To explore the cause of abortion and strategy of prenatal diagnosis for pregnant women with high risk for chromosomal abnormalities by using copy number variation sequencing (CNV-seq) and short tandem repeats (STR) analysis. METHODS: A total of 36 samples were collected, including amniotic fluid, abortion tissue, whole blood, chorionic villi and umbilical cord blood. CNV-seq and STR analysis were carried out to detect microdeletions, microduplications, chromosomal aneuploidies, mosaicisms and triploidies. RESULTS: Among all samples, 1 was detected with 4p15.1p16.3 and 14q11.1q22.1 duplication, 1 was detected with 19p13.3 deletion, 8 were detected with chromosomal aneuploidies, 4 were detected with mosaicisms, two were detected with triploidies. No definite pathogenic CNVs were detected in 20 samples, which yielded a positive detection rate of 44.44%. CONCLUSION As a high-throughput detection method, CNV-seq has the advantages of rapidity, simplicity and high accuracy. It may suit prenatal diagnosis and analysis of abortion factors in combination with STR analysis.
Abortion, Spontaneous/genetics* ; DNA Copy Number Variations ; Female ; Humans ; Karyotyping ; Microsatellite Repeats ; Pregnancy ; Prenatal Diagnosis

Recurrent spontaneous abortion (RSA) defines as two or more consecutive losses at < or =20 weeks of gestation and affects an estimated 1 of every 100 couples wishing to have children. However, it remains a poorly understood phenomenon. Recent reports observed a significant association between highly skewed X chromosome and RSA, supporting that X chromosome inactivation might be an important and previously unknown cause of RSA. X-inactivation pattern, using polymeric X-linked women with idiopathic RSA and 80 control subjects with a single successful pregnancy and no history of spontaneous abortion. The ratio of heterozygotes was 68.2% (45/66) in women with RSA and 67.5% (54/80) in control group. Among 45 informative RSA cases, only 1 (2.2%) woman showed extreme skewed X inactivation (> or =90%) and 4 (8.9%) had mild skewed inactivation (> or =85%). In 54 heterozygous control subjects, 5 (9.3%) women showed extreme skewed X inactivation and 7 (13.0%) had mild one. The frequency of skewed X inactivation between RSA patients and control group was not significantly different (p>0.05). This finding suggests that skewed x romosome be not associated with unexplained RSA patients.
Abortion, Habitual/*genetics ; Abortion, Spontaneous/*genetics ; Adult ; DNA Methylation ; *Dosage Compensation (Genetics) ; Female ; Heterozygote ; Human ; Korea ; Linkage (Genetics) ; Lymphocytes ; Pregnancy ; Support, Non-U.S. Gov't

OBJECTIVETo study the relationship between azoospermia factor (AZF) microdeletions of the Y-chromosome and recurrent spontaneous abortion.

METHODSWe collected 26 chorionic villus samples from abortive male embryos and 51 blood samples from the husbands whose wives had recurrent spontaneous abortion, extracted genomic DNA from the samples and detected 12 STSs in the AZFa, AZFb and AZFc regions of Yq11.2 by amplification multiplex PCR.

RESULTAZF microdeletions were found neither in the chorionic villus samples nor in the blood samples.

CONCLUSIONThere is no relationship between AZF microdeletions and recurrent spontaneous abortion.

Abortion, Habitual ; genetics ; Abortion, Spontaneous ; genetics ; Chromosome Deletion ; Chromosomes, Human, Y ; Female ; Genetic Loci ; Humans ; Male ; Polymerase Chain Reaction ; methods ; Pregnancy ; Seminal Plasma Proteins ; genetics

OBJECTIVE: To assess the value of chromosomal microarray analysis (CMA) for the analysis of 824 samples from miscarriage or stillbirth. METHODS: Copy number variations (CNVs) in the abortic chorionic villi or stillbirth tissues were detected by CMA. RESULTS: All specimens were successfully analyzed, among which 381 (46.2%) were diagnosed with chromosomal abnormalities, which included 312 (81.9%) numerical abnormalities, 66 (17.3%) structural abnormalities and 3 (0.8%) uniparental disomies. Among numerical chromosomal abnormalities, aneuploidies was most common (92.0%), with trisomy 16 and 45,X accounting for 41 (13.1%) and 63 (20.2%) of the cases, respectively. Among the 66 structural chromosomal aberrations, there were 26 (39.4%) CNVs duplications, 20 (30.3%) CNVs deletions, and 20 (30.3%) CNVs duplication and deletions. 33 CNVs were predicted as have a high chance to lead to a disease. CONCLUSION CMA is a reliable, robust, and high-resolution method for the analysis of miscarriage or stillbirth samples. Numerical aberrations, in particular chromosomal aneuploides, are the main cause for spontaneous abortions and stillbirths.
Abortion, Spontaneous ; genetics ; Chromosome Aberrations ; Chromosome Disorders ; diagnosis ; genetics ; DNA Copy Number Variations ; Female ; Humans ; Microarray Analysis ; Pregnancy ; Stillbirth ; genetics

OBJECTIVETo investigate the value of fetal chromosomal karyotype analysis in cases of early spontaneous abortion.

METHODSChorionic villus specimens obtained from 110 cases of early spontaneous abortion were cultured for karyotype analysis.

RESULTSOf the 110 cases, chorionic villus was successfully cultured in 103 cases (93.7%), and abnormal embryo karyotypes were identified in 52 cases (50.5%). Trisomy was the most frequent embryo karyotype abnormalities in these cases, and chromosomal aberration occurred in 29 cases (52.9%) of the first spontaneous abortion and in 23 cases (42.6%) of repeated abortions. Female fetuses accounted for 75.5% (78 cases) in the spontaneously aborted fetuses and for 67.3% (35 cases) in fetuses with chromosomal abnormalities.

CONCLUSIONEmbryo chromosomal abnormality is the most important reason of early spontaneous abortion, and karyotype analysis of the villus helps identify the causes of abortion and ensure the success of the next pregnancy.

Abortion, Spontaneous ; genetics ; pathology ; Adult ; Cells, Cultured ; Chorionic Villi ; pathology ; Female ; Humans ; Karyotyping ; Pregnancy ; Pregnancy Trimester, First ; Trisomy ; genetics