Chromosomal abnormalities and polymorphic variants in couples with repeated miscarriage in Mexico

Chromosome analysis of foetal tissue from 1903 spontaneous abortion patients in 5 regions of China: a retrospective multicentre study

BACKGROUND

Abnormal foetal tissue chromosome karyotypes are one of the important pathogenic factors for spontaneous abortion (SA). To investigate the age and abnormal foetal karyotypes of 1903 couples who experienced SA.

METHODS

A retrospective multicentre study collected age and foetal tissue karyotypes CNV-seq data of 1903 SA couples from 6 hospitals in 5 regions from January 2017 to March 2022. The distribution and correlation of abnormal foetal tissue karyotypes were evaluated by using regions and age.

RESULTS

In our study, 1140 couples (60.5% of the total) had abnormal foetal tissue chromosome karyotypes in all regions. We found that there were differences in the number of abnormal foetal tissue chromosome karyotypes, of which the incidence of trisomy was higher. At the same time, the populations situated in the eastern region had a more triploid (15.5%) distribution, trisomy (58.1%) in the southern region, mosaicism (14.8%) and microduplication (31.7%) in the southwestern region, microdeletion (16.7%) in the northern region. There are variances across areas, and it is more common in the north. The incidence risk of prenatal chromosomal abnormalities varied according to age group.

CONCLUSION

The findings of this study suggest that the karyotypes of patients with abnormal foetal tissue chromosome abortion in different regions were different. Meanwhile, patients ≥ 35 years old had a higher risk of abnormal foetal tissue chromosome abortion.

The pattern of chromosomal abnormalities in recurrent miscarriages: a single center retrospective study

BACKGROUND

Chromosomal abnormalities are more common in first trimester recurrent miscarriages (RM). Chromosomal anomalies affect approximately 2%-8% of couples with RM.

OBJECTIVES

Evaluate the spectrum and the frequencies of chromosomal anomalies in RM.

DESIGN

A retrospective hospital record-based descriptive study.

SETTING

A tertiary care center in Turkey.

PATIENTS AND METHODS

We studied couples with RM between October 2020 and January 2022. Relevant family and medical history, clinical examination and the results of karyotype were statistically analyzed.

MAIN OUTCOME MEASURES

Prevalence and types of chromosomal aberrations in couples with RM. SAMPLE SİZE: 362 couples with a history of RM RESULTS: Among the 362 couples, 14 cases (3.86%) had chromosome abnormalities. Eight cases (57.14%) were structural anomalies and six cases (42.86%) were numerical chromosomal aberrations. We found five balanced translocations (67.5%) and three Robertsonian translocations (37.5%). The prevalence of polymorphic variants was 51/362 (14.1%).

CONCLUSIONS

This study supports the conclusion that clinicians should understand the importance of chromosome analysis in these couples and direct them to karyotyping after two abortions in order to exclude the possibility of a genetic cause of RM.

LIMITATIONS

Single-center study and retrospective.

CONFLICT OF INTEREST

None.

Analysis of Aneuploidy Rate and Pregnancy Outcomes in Unexplained Recurrent Pregnancy Loss Couples With Chromosome Polymorphism After PGT-A

Purpose

The study aims to investigate whether chromosomal polymorphism affects embryo development and pregnancy outcomes of unexplained recurrent pregnancy loss (uRPL) couples undergoing PGT-A.

Methods

A total of 585 couples with uRPL history who performed PGT-A were included in the retrospective study from January 2016 to December 2020. We included 415 couples with normal karyotype and 170 couples with chromosomal polymorphism. Furthermore, the polymorphism group was divided into two subgroups: 113 couples in the male group and 57 couples in the female group. The embryo development and pregnancy outcomes were analyzed in different groups.

Results

The blastocyst rate and aneuploidy rate are statistically different in the normal group, male polymorphism group, and female polymorphism group. Compared with normal and female groups, the male group has a lower blastocyst rate, which is statistically different (48.3 vs. 53.9%, p = 0.003; 48.3 vs. 54.1%, p = 0.043). Moreover, the aneuploidy rate of the male polymorphism group is significantly higher than female carriers (29.5 vs. 18.6%, p = 0.003). However, there were no statistically significant differences in clinical pregnancy rate, early miscarriage rate, and live birth rate after PGT-A (p > 0.05).

Conclusion

Male with chromosome polymorphism (CPM) have a lower blastocyst rate and a higher aneuploidy rate than female carriers in uRPL couples undergoing PGT-A. However, when a euploid blastocyst was first transferred, no difference in pregnancy outcomes was found between the male and female polymorphism carriers. It indicated that CPM may have an adverse effect on the embryos of male carriers with uRPL history, and the occurrence of uRPL may be decreased in male polymorphism carriers after PGT-A.

Application of array comparative genomic hybridization (aCGH) for identification of chromosomal aberrations in the recurrent pregnancy loss

Spontaneous abortion occurs in 8–20% of recognized pregnancies and usually takes place in the first trimester (7–11 weeks). There are many causes of pregnancy loss, but the most important (about 75%) is the presence of chromosomal aberrations. We present the results of oligonucleotide array application in a cohort of 62 miscarriage cases. The inclusion criteria for the study were the loss after 8th week of pregnancy and the appearance of recurrent miscarriages. DNA was extracted from trophoblast or fetal skin fibroblasts. In the 62 tested materials from recurrent miscarriages, the detection rate was 56.5% (35/62). The most commonly found were aneuploidies (65%) (chromosomal trisomy 14, 16, 18, 21, and 22), Turner syndrome, and triploidy (17.1%). Other chromosomal abnormalities included pathogenic and likely pathogenic structural aberrations: 1) pathogenic: deletion 7p22.3p12.3 and duplication 9p24.3p13.2 inherited from the normal father, deletion 3q13.31q22.2 and deletion 3q22.3q23 of unknown inheritance and duplication of 17p12 inherited from father with foot malformation; 2) likely pathogenic variants: deletion 17p13.1 inherited from normal mother, deletion 5q14.3 of unknown inheritance and de novo deletion 1q21.1q21.2. Among these aberrations, six CNVs (copy number variants) were responsible for the miscarriage: deletion 7p22.3p12.3 and duplication 9p24.3p13.2, deletion 3q13.31q22.2 and deletion 3q22.3q23, and deletion 17p13.1 and deletion 1q21.1q21.2. Other two findings were classified as incidental findings (deletion 5q14.3 and 17p12 duplication). Our research shows that 17% of the aberrations (6/35 abnormal results) that cannot be identified by the routine kariotype analysis are structural aberrations containing genes important for fetal development, the mutations of which may cause spontaneous abortion.

Comprehensive assessment of a clinic's experience of preimplantation genetic testing by a cumulative rate

OBJECTIVE

This study aimed to investigate the outcomes of patients who had preimplantation genetic testing for chromosomal structural rearrangement (PGT-SR) or for aneuploidy screening (PGT-A) with different indications.

METHODS

This was a retrospective study at a single center. Pregnancy outcomes of all couples who had PGT from 2014 to 2018 were retrospectively analyzed, and the cumulative pregnancy rates (CPR) and the cumulative live birth/ongoing pregnancy rate (CLB/OPR) per patient with at least one transfer cycle were calculated.

RESULTS

A total of 313 PGT-SR cycles of 255 patients, 22 PGT-sexing cycles of 20 patients, and 190 PGT-A cycles of 168 patients were performed during the period. In PGT-SR, the overall CPR and the CLB/OPR were 68.04% and 59.79%, respectively. In PGT-A, the CPR and CLB/OPR were 67.52% and 58.12%, respectively. We also found that the CPR (93.75%) and CLB/OPR (87.50%) were highest in patients for PGT-sexing with a diagnosis of Y chromosomal microdeletion. In addition, we discovered a significant trend that aneuploidy rate significantly increased with maternal age (p = 0.000) in PGT-A population. No significant difference was found in the mosaicism rate or clinical outcomes among the age groups. Similarly, the significance was absent in the PGT-SR population.

CONCLUSION

We reviewed the CPR and CLB/OPR for different indications since the 24-chromosome technique has been applied in the clinical setting for 4 years in our center. We hope that our results will provide some pointed guidance and a new perspective on outcomes for PGT in certain patients and clinicians.

The Arachidonic Acid Metabolism Mechanism Based on UPLC-MS/MS Metabolomics in Recurrent Spontaneous Abortion Rats

Recurrent spontaneous abortion (RSA) remains a critical and challenging problem in reproduction. To discover novel biomarkers for RSA, ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) metabolomics approach was applied to detect RSA serum metabolic profiles and explore its possible pathogenesis and mechanism. The abortion rat model was established, and a metabolomics analysis was performed to evaluate the differentially expressed metabolites between the control and model groups. Immunohistochemistry (IHC), qRT-PCR, and Western blot further examined the expression of Arachidonic acid metabolism-related genes in uterus tissues. To identify arachidonic acid metabolism-related changes in RSA, ELISA's potential mechanisms were further confirmed in serum. Ninety-one metabolites were significantly different between the two groups, as indicated by a VIP ≥1, fold change ≥1. The metabolic pathways involving arachidonic acid metabolism pathway (P = 0.00044) are related to RSA. Verification by experimental showed that compared with the control rats, the expression of the COX-1, COX-2, PTGFR, and TBXA2R genes associated with the arachidonic acid metabolism pathway has significantly increased the uterus and serum of RSA rats (P < 0.05). Regulation of the arachidonic acid metabolism pathway might serve as a promising therapeutic strategy for relieving RSA women's symptoms.

Cytogenetic Analysis of 570 Couples with Recurrent Pregnancy Loss: Reporting 11 Years of Experience

Objectives

Recurrent pregnancy loss (RPL) is a serious complication of pregnancies, affecting almost 2%-5% of couples. Among numerous underlying causes, chromosomal anomalies in one of the partners are regarded as important issues, with varying frequencies among different populations. In this study, we aimed to determine the prevalence of chromosomal abnormalities and chromosome polymorphisms in couples with a history of RPL from Kermanshah province, west of Iran.

Materials and Methods

In this 11-year retrospective study, a total of 1140 cases with two or more spontaneous abortions were recruited and studied according to standard cytogenetic analysis.

Results

From a total of 1140 reviewed blood samples, 1011 people (88.5%) had a normal karyotype and 129 people (11.5%) had chromosomal aberrations. These aberrations were found in 62 females and 67 males. The prevalence of chromosomal abnormalities was as follows: 18 (1.5%) structural aberrations, 1 numerical anomaly and 110 (9.6%) apparently normal polymorphic variants.

Conclusions

Our findings could determine the underlying cause of RPL in 1.5% of the population while the majority still remained unexplained. This emphasizes the importance of searching for other genetic and nongenetic causes of RPL in apparently idiopathic cases of RPL.

[Chromosomal polymorphisms are associated with blastomere multinucleation in IVF/ICSI cycles]

OBJECTIVE

To investigate the association of chromosomal polymorphisms with multinucleated embryos in infertile couples undergoing in vitro fertilization-intracytoplasmic sperm injection (IVF-ICSI).

METHODS

This retrospective case-control study was conducted among 1145 infertile couples undergoing their first IVF/ICSI cycles. According to their karyotype, the couples were divided into chromosomal polymorphism group and control group, and the former group was divided into 3 subgroups: inversion group, D and G genome polymorphic group and 1, 9, and 16 qh+group. The blastomere multinucleation rate, clinical pregnancy rate and live birth rate were compared between the groups.

RESULTS

Of the total of 1145 couples, 139 (6.10%) had chromosomal polymorphisms at least in one partner. No significant differences were found in female age, BMI, basal FSH level, total gonadotropin dose, E₂ level on day of HCG, number of oocytes retrieved, fertilization rate, top quality embryo rate, clinical pregnancy rate or live birth rate among the groups (P > 0.05). The multinuclear rate of the embryos in couples with pericentric inversion of chromosomes 1, 9, and Y chromosomes and those with D and G genome polymorphisms were 8.23% and 4.65%, respectively, significantly higher than that in the control group (2.69%; P < 0.05); the multinuclear rate of the embryos was 2.77% in 1, 9, and 16 qh+ group, similar with that in the control group (P > 0.05).

CONCLUSIONS

Infertile couples with pericentric inversion of chromosomes 1, 9, and Y chromosomes and in those with D and G genome polymorphism are at higher risks of blastomere multinucleation in IVF- ICSI cycles; 1, 9, and 16 qh + polymorphisms do not increase the rate of blastomere multinucleation of the embryos.

Six families with balanced chromosome translocation associated with reproductive risks in Hainan Province: Case reports and review of the literature

BACKGROUND

Balanced translocation refers to the process where breakage and reconnection of chromosomes occur at abnormal positions. As the genetic substance with balanced translocation in individuals does not change, which is usually characterized by normal phenotype and intelligence, the individuals seek medical service after many miscarriages, resulting in considerable mental and physical burdens of the family members. In the current era with rapid advances in detection technology, cytogenetic examination, as a definitive approach, still plays an essential role.

CASE SUMMARY

We report six cases with balanced chromosome translocation: Case 1: 46,XY,t(3;12)(q27;q24.1), infertility after 3 years of marriage; Case 2: 46,XX,t(4;16)(q31;q12), small uterus and irregular menstruation; Case 3: 46,XY,t(4;5)(q33;q13),9qh+, not pregnant after arrested fetal development; Case 4: 46,XX,t(11;17)(q13;p11.2), not pregnant after two times of spontaneous abortion; Case 5: 46,XX,t(10;13)(q24;q21.2), not pregnant after arrested fetal development for once; Case 6: 46,XX,t(1;4)(p36.1;q31.1), not pregnant after arrested fetal development for two times. The first four cases had chromosomal aberration karyotypes.

CONCLUSION

These results suggested that balanced chromosomal translocation carriers are associated with reproductive risks and a very high probability of abnormal pregnancy. The discovery of the first four reported chromosomal aberration karyotypes provides an important basis for studying the occurrence of genetic diseases.

Combination of QF-PCR and aCGH is an efficient diagnostic strategy for the detection of chromosome aberrations in recurrent miscarriage

Background

Our aim was to conduct a comprehensive genetic evaluation using the combination of QF‐PCR (quantitative fluorescence polymerase chain reaction) and aCGH (array comparative genomic hybridization) for the detection of the frequency and type of chromosome aberrations in recurrent miscarriage (RM) in the clinical setting.

Methods

This retrospective study was conducted on 73 first‐trimester products of conception (POC) between September 2014 and February 2017. The POCs were collected from 73 women with at least one previous miscarriage and analyzed for chromosomal anomalies using QF‐PCR and aCGH as part of the routine clinical evaluation.

Results

Chromosome aberrations were detected in 52/73 POCs (71.2%), of which 41 (56.2%) were identified by QF‐PCR and an additional 11 (15.1%) by aCGH. Numerical aberrations constituted 92.3% of abnormalities, with trisomies as the most common subtype (72.9%). Causative structural aberrations were found in three samples (5.8%). The frequency of chromosome aberrations was not dependent on the number of previous miscarriages, whereas it significantly increased with advanced maternal age.

Conclusion

Our results confirm that chromosome aberrations are the most common cause of RM and that QF‐PCR and aCGH combination should be included in the routine genetic analysis of POCs of couples with miscarriage.

Novel high-coverage targeted metabolomics method (SWATHtoMRM) for exploring follicular fluid metabolome alterations in women with recurrent spontaneous abortion undergoing in vitro fertilization

The complexity of follicular fluid metabolome presents a significant challenge for qualitative and quantitative metabolite profiling, and for discovering the comprehensive biomarkers. In order to address this challenge, a novel SWATHtoMRM metabolomics method was used for providing broad coverage and excellent quantitative capability to discover the human follicular fluid metabolites related to recurrent spontaneous abortion (RSA) after in vitro fertilization and embryo transfer, and to evaluate their relationship with pregnancy outcome. The follicular fluid samples from the spontaneous abortion group (n = 22) and the control group (n = 22) were analyzed using ultra-performance liquid chromatography high-resolution mass spectrometry. A novel, high-coverage, targeted metabolomics method (SWATH to MRM) and a targeted metabolomics method were used to find and validate the differential metabolites between the two groups. A total of 18 follicular fluid metabolites, including amino acids, cholesterol, vitamins, fatty acids, cholic acid, lysophosphatidylcholine and other metabolites, were identified. In the RSA group, 8 metabolites, namely dehydroepiandrosterone, lysoPC(16:0), lysoPC(18:2), lysoPC(18:1), lysoPC(18:0), lysoPC(20:5), lysoPC(20:4), and lysoPC(20:3), were up-regulated, and 10 metabolites, namely phenylalanine, linoleate, oleic acid, docosahexaenoic acid, lithocholic acid, 25-hydroxyvitamin D3, hydroxycholesterol, 13-hydroxy-alpha-tocopherol, leucine, and tryptophan, were down-regulated. These differential metabolites related to RSA may provide a possible diagnostic basis and therapeutic target for RSA, as well as a scientific basis for elucidating the mechanism of RSA.

The type and prevalence of chromosomal abnormalities in couples with recurrent first trimester abortions: A Turkish retrospective study

OBJECTIVE

Chromosomal abnormalities are more common in the first trimester abortions. We aimed to investigate the types and prevalence of chromosomal abnormalities in couples with recurrent first trimester miscarriages in Sivas, Turkey.

MATERIALS AND MEDHODS

Three hundred couples (600 individuals) who had a story of recurrent abortion were included in the study. Chromosome analysis was performed after the preparation of lymphocyte culture with the standard method. Karyotype analyses were supported by FISH and aCGH studies.

RESULTS

Total 26 chromosome abnormalities (8.7%) were found in the couples (19 females and 7 males). Fifteen cases (57.7%) were structural anomalies and eleven cases (42.3%) were numerical chromosomal aberrations. We detected 5 balanced translocations (33.3%), 4 Robertsonian translocations (26.7%), 3 inversions (20%), 2 duplications (13.3%) and one deletion (6.7%) among the structural anomalies. Mosaic monosomy X in five cases (45.4%), the combination of mosaic monosomy-trisomy X in three cases (27.3%), the combination of mosaic monosomy-trisomy and tetrasomy X in two cases (18.2%) and mosaic pentasomy X in only one individual (9.1%) were encountered as numerical chromosome aberrations. 19 cases had heterochromatic changes or other chromosomal variations (satellite increments and inv9).

CONCLUSION

Chromosome analysis in couples with recurrent miscarriage is necessary for possible preimplantation genetic diagnosis. As well as numerical and structural chromosome abnormalities, some chromosomal variations (heterochromatin and satellite increments etc.) may also contribute to recurrent miscarriages. Numerical chromosomal abnormalities are often associated with sex chromosomes and usually seen in females.

Chromosomal abnormalities in couples with recurrent spontaneous miscarriage: a 21-year retrospective study, a report of a novel insertion, and a literature review

PURPOSE

The aim of this study is to evaluate the frequency and nature of chromosomal abnormalities in Moroccan couples with recurrent spontaneous miscarriage (RSM). In addition, the data were compared with those reported elsewhere in order to give a global estimation of chromosomal abnormalities frequencies.

METHODS

The study was performed for all couples with RSM who were referred to the cytogenetic department, Pasteur Institute of Morocco, from different hospitals in Morocco between 1996 and 2016. Cytogenetic analysis was performed according to the standard method.

RESULTS

Among 627 couples with RSM, the chromosomal abnormalities were identified in 11.00% of couples, with chromosomal inversions in 4.30%, reciprocal translocations in 2.71%, Robertsonian translocations in 1.43%, and deletion, isochromosome, and insertion in 0.15% each. The insertion identified [46,XX,ins(6)(p24q21q27)] is new, and is the fourth reported in association with RSM. The mosaic karyotypes were observed in 0.64%, polymorphic variants were identified in 1.27%, and numerical aneuploidy was observed in 0.15%. In regrouping our results with those in 27 other studies already published in 21 different countries, we obtained the frequency of chromosomal abnormalities in couple with RSM to be 5.16% (991/19197 couples). The reciprocal translocation was the most frequent with 2.50%, followed by Robertsonian translocation 0.83% and inversions 0.77%. The other types of chromosomal abnormalities were present with 0.98% in the world.

CONCLUSION

This data showed that the frequency of chromosomal abnormalities in Moroccan couples with RSM is 11.00%, and in regrouping our results with other studies, the frequency changes to 5.16%.

Cytogenetic screening in couples with Habitual Abortions

OBJECTIVE

Habitual abortion (HA) is defined at least three consecutive pregnancy losses. One of the etiologic causes is parental chromosomal anomalies. In this study, we aimed to that investigate the effect of parental chromosomal abnormalities on HA.

METHODS

The cytogenetic results of patients with at least three abortions referred to our university hospital between January 2010 - March 2017 were evaluated. A total of 1154 couples with HA were analysed. Peripheral lymphocyte cultures incubated for 72 h were used for karyotype analysis via the Giemsa banding technique.

RESULTS

Of a total 1154 couples (2308 patients) 37 female (3.2%) and 17 male (1.47%) had abnormal karyotypes. Reciprocal translocation carriage (n = 26; 1.12%) was the most commonly detected structural anomaly, followed by X chromosome mosaicism (n = 16; 0.69%),Robertsoniantranslocation (n = 9; 0.38%), Chromosomal inversion (n = 6; 0.26%). Chromosomal polymorphisms, which are considered minor chromosomal changes, were detected in 221 (9.57%) individuals.

CONCLUSION

Our study exhibits that chromosomal analysis in patient with HA is an appropriate approach to elucidate the aetiology of HA. Data from cytogenetic screening can be used in guiding couples planning future pregnancies and in prenatal diagnosis of chromosomal anomalies in the foetus.

Prevalence of Cytogenetic Anomalies in Couples with Recurrent Miscarriages: A Case-control Study

Background:

About 15%–20% of couples get affected by recurrent miscarriages (RM) and chromosomal abnormality in one partner affects 3%–6% of RM couples.

Aims:

The present study aimed to determine the prevalence of cytogenetic anomalies in couples with RM.

Settings and Design:

A case–control study was undertaken, in which 243 couples who had experienced 2 or >2 miscarriages were investigated for chromosomal abnormalities and compared with 208 healthy, age-matched control couples who had at least one healthy live born and no history of miscarriages.

Material and Methods:

Peripheral blood (PB) lymphocytes were cultured using PB-Max Karyotyping medium (GIBCO) for chromosomal analysis and 20 metaphases were analyzed for each individual.

Statistical Analysis:

Student's t-test was used for statistical evaluation and P < 0.05 was considered statistically significant for all instances.

Results:

The current study revealed 3.1% RM cases showing structural chromosomal aberrations, of which balanced translocations and Robertsonian translocations constituted 66.7% and 26.7% cases, respectively, while inversions constituted 6.7% abnormal RM cases. Polymorphic variations were observed in 1.9% RM patients and 1.2% controls as well. However, the number of abortions were significantly more (P = 0.027) in male carriers of balanced translocations as compared to female carriers in the RM group. There was no significant difference for age (P = 0.539) between RM women and control women.

Conclusions:

Although similar studies exist in literature, our study is the first of its kind from our region that has compared the chromosomal anomalies between the RM group and the control group. We observed 3.1% of balanced translocations and an increased number (though nonsignificant) of polymorphic variations and satellite associations in the RM group as compared to the control group.

Chromosomal polymorphisms are independently associated with multinucleated embryo formation

PURPOSE

The purpose of this study is to explore the factors associated with embryo multinucleation, particularly focused on the influence of parental chromosomal polymorphisms in embryo multinucleation.

METHODS

This is a retrospective case-control study involving 1260 infertile couples undergoing their first IVF/ICSI cycles. Couples were screened for abnormalities in their karyotype and were evaluated for blastomere persistence of multinucleation. Demographic characteristics, stimulation protocol, and pregnant outcomes were analyzed using logistic regression analysis.

RESULTS

The level of basal FSH was lower in the multinucleated embryos group (5.37 vs 5.72 IU/L). The Multinucleated embryos group received less gonadotropins (1788.5 vs 1891.3 IU), and the level of LH on day of HCG triggering was lower (1.09 vs 1.30 IU/L). More oocytes were recovered in the multinucleated embryos group (11.51 vs 9.23). Chromosomal polymorphisms were seen in at least 1 out of 163 (12.9%) couples. Multivariate logistic regression analysis revealed that chromosomal polymorphisms were independently associated with an increase in the occurrence risk of multinucleated embryos (OR = 1.61, 95% CI, 1.06-2.44) in the first IVF/ICSI cycle. The miscarriage rate in the multinucleated embryos group was 10% higher than that of the control group.

CONCLUSIONS

Chromosomal polymorphisms were independently associated with multinucleation embryo formation. A higher LH level on the day of HCG triggering was associated with a decreased chance of multinucleation.

Male chromosomal polymorphisms reduce cumulative live birth rate for IVF couples

PURPOSE

Chromosomal polymorphisms are associated with infertility, but their effects on assisted reproductive outcomes are still quite conflicting, especially after IVF treatment. This study evaluated the role of chromosomal polymorphisms of different genders in IVF pregnancy outcomes.

METHODS

Four hundred and twenty-five infertile couples undergoing IVF treatment were divided into three groups: 214 couples with normal chromosomes (group A, control group), 86 couples with female polymorphisms (group B), and 125 couples with male polymorphisms (group C). The pregnancy outcomes after the first and cumulative transfer cycles were analyzed, and the main outcome measures were live birth rate (LBR) after the first transfer cycle and cumulative LBR after a complete IVF cycle.

RESULTS

Comparison of pregnancy outcomes after the first transfer cycle within group A, group B, and group C demonstrated a similar LBR as well as other rates of implantation, clinical pregnancy, early miscarriage, and ongoing pregnancy (P > 0.05). However, the analysis of cumulative pregnancy outcomes indicated that compared with group A, group C had a significantly lower LBR per cycle (80.4 vs 68.00%), for a rate ratio of 1.182 (95% CI 1.030 to 1.356, P = 0.01) and a significantly higher cumulative early miscarriage rate (EMR) among clinical pregnancies (7.2 vs 14.7%), for a rate ratio of 0.489 (95% CI 0.248 to 0.963, P = 0.035).

CONCLUSION

Couples with chromosomal polymorphisms in only male partners have poor pregnancy outcomes after IVF treatment manifesting as high cumulative EMR and low LBR after a complete cycle.

Y chromosome polymorphisms may contribute to an increased risk of male-induced unexplained recurrent miscarriage

The present study aims to explore the relationship between the Y chromosome polymorphisms (1qh+, inv(9), 9qh+, 16qh+, group D/G, Yqh– and Yqh+) and the risk of unexplained recurrent miscarriage (URM). A total of 507 couples with URM were recruited as case group and 465 healthy couples as control group. The Y chromosome polymorphisms of the male individuals were analysed with the G-banding technique, and the results of the chromosome G-banding analysis were determined using the International Naming Standards of Human Genetics (ISCN). Logistic regression analysis was used to analyse the risk factors for URM. The detection rate of Y chromosome polymorphisms in the case group (12.03%) was higher than that in the control group (2.15%). Y chromosome polymorphisms were detected at significantly higher rates in the case group than in the control group. Using the normal Y chromosomes in individuals of the case group as reference, the partners of their counterparts were more likely to experience miscarriage. The couples who were Y chromosome-polymorphism carriers had shorter gestational age, increased frequency of URM and longer average interval between pregnancies. The results of logistic regression analysis revealed that Y chromosome polymorphisms, shorter gestational age, a higher frequency of miscarriage and longer pregnancy interval were independent risk factors for URM. Y chromosome polymorphisms may be associated with the risk of URM and may play an important role in the development of URM.

Associations of recurrent miscarriages with chromosomal abnormalities, thrombophilia allelic polymorphisms and/or consanguinity in Saudi Arabia

BACKGROUND

Recurrent pregnancy loss (RPL) or recurrent spontaneous abortion is an obstetric complication that affects couples at reproductive age. Previous reports documented a clear relationship between parents with chromosomal abnormalities and both recurrent miscarriages and infertility. However, limited data is available from the Arabian Peninsula which is known by higher rates of consanguineous marriages. The main goal of this study was to determine the prevalence of chromosomal abnormalities and thrombophilic polymorphisms, and to correlate them with RPL and consanguinity in Saudi Arabia.

METHODS

Cytogenetic analysis of 171 consent patients with RPL was performed by the standard method of 72-h lymphocyte culture and GTG banding. Allelic polymorphisms of three thrombophilic genes (Factor V Leiden, Prothrombin A20210G, MTHFR C677T) were performed using PCR-RFLP (restriction fragment length polymorphism) and gel electrophoresis.

RESULTS

Data analysis revealed that 7.6 % of patients were carrier of numerical or structural chromosomal abnormalities. A high rate of translocations (46 %) was associated to increased incidence of RPL. A significant correlation between consanguineous RPL patients and chromosomal abnormalities (P < 0.05) was found. Both Factor V Leiden and Prothrombin A20210G allelic polymorphisms were significantly associated with a higher prevalence of RPL.

CONCLUSIONS

This study demonstrated a strong association between RPL and the prevalence of chromosomal abnormalities and inherited thrombophilia. Given the high rate of consanguineous marriages in the Saudi population, these results underline the importance of systematic cytogenetic investigation and genetic counseling preferably at the premarital stage or at least during early pregnancy phase through preimplantation genetic diagnosis (PGD).

Chromosomal analyses of 1510 couples who have experienced recurrent spontaneous abortions

In this retrospective study, karyotype results of 1510 couples with a history of recurrent spontaneous abortion were evaluated. The study was conducted at Balcalı Hospital in Adana region of Turkey. For all cases, peripheral blood lymphocytes were cultured for chromosome study using the standard method. Chromosome aberrations were detected in 62 couples (4.1% of all couples). At an individual level, chromosome aberrations were found in a total of 65 cases (41 females and 24 male cases), with structural chromosomal aberrations in 58 cases including balanced translocations in 30 cases, Robertsonian translocations in 12 cases, deletions in seven cases, inversions in nine cases and numerical chromosome aberrations in seven cases. The results of the study indicated that structural aberrations, particularly translocations, were the most common type of aberration observed among couples who had experienced recurrent spontaneous abortions and that these couples might benefit from cytogenetic analyses.

Somatic/gonadal mosaicism for structural autosomal rearrangements: female predominance among carriers of gonadal mosaicism for unbalanced rearrangements

Background

Mosaicism for chromosomal structural rearrangements (Rea) is rare and the timing and mechanisms of mosaic Rea formation, maintenance, and clinical manifestation are poorly understood. To date, there are no published data on the cytogenetic profile of mosaic Reas. The question as to whether the proportion of abnormal cells in the carrier’s cultured blood is clinically significant remains unanswered. A previous study showed a strong female preponderance among carriers of mosaicism for Rea with pericentromeric breaks, indicating female-specific instability in early embryos. However, there is no corresponding study on male to female sex ratio (SR) among carriers of somatic and/or gonadal mosaicism for non-centromeric Rea. Population rates of mosaic Rea carriers calculated from consecutive series of patients referred for various reasons and from prenatal samples have not been established. Therefore the objectives of the present study were several-fold: (1) a study on profiles of Rea involved, (2) comparative analysis of the proportion of cells with unbalanced Rea in blood cultures from asymptomatic and affected carriers, (3) comparative analysis of SR in carriers of mosaicism for balanced and unbalanced Rea, and (4) determination of the population frequency of mosaicism for autosomal Rea.

Results

One hundred and three cases of mosaicism for autosomal non-centromeric Rea (N/Rea; normal line/structural rearrangement) in which the sex of the carrier had been specified were identified in the literature. Among balanced Rea, there was a prevalence of reciprocal translocations (89 %) over inversions (11 %). Among unbalanced Rea, deletions were the most frequent (40 %), followed by duplications (25 %) and rings (16 %). Derivatives and other chromosome abnormalities were less frequent (9 and 10 %). Eight of eleven (73 %) affected carriers of unbalanced Rea displayed a high proportion (>50 %) of abnormal cells compared to 4/37 (11 %) in asymptomatic carriers, p < 0.0001. Among carriers of mosaicism for balanced Rea there was a slight male predominance, 24 M/22 F, unlike the strong female predominance among carriers of mosaicism for unbalanced Rea, 11 M/46 F, p < 0.0001. Among ten carriers of unbalanced Rea with reproductive failure, only one was a male with infertility, and one was a partner of a woman experiencing recurrent spontaneous abortion. Population rates of mosaics for reciprocal translocaton (N/rcp), inversion (N/inv), and unbalanced Rea (N/unbal Rea) calculated from published data on consecutive series of patients with reproductive failures were 0.02 ‰, 0.005 ‰, and 0.002 ‰, correspondingly. Among 30,376 infertile patients three carriers of mosaicism for balanced Rea were identified (two cases of N/rcp and one case of N/inv), whereas among 26,384 patients with habitual abortion seven carriers were detected (five N/rcp and two N/inv). Among all 56,760 tested patients with reproductive failures only one was found to be a carrier of mosaicism for an unbalanced Rea (N/del, mosaicism for deletion).

Conclusions

A high proportion of Rea cells (>50 %) detected in cultured T-lymphocytes is associated with clinical manifestation of chromosomal imbalance. A strong female prevalence among carriers of mosaicism for unbalanced Rea suggests male-specific selection against abnormal cells rather than impairment of male gametogenesis, as the latter suggests a better prognosis for male fetuses. These findings should be taken into consideration when genetic counseling of patients referred after a diagnosis of mosaicism for an unbalanced rearrangement in a fetus.

Effect of chromosomal polymorphisms of different genders on fertilization rate of fresh IVF-ICSI embryo transfer cycles

To explore whether chromosomal polymorphisms of different genders affect outcomes of fresh IVF and intracytoplasmic sperm injection (ICSI) embryo transfer cycles differently, 37 couples with chromosomal polymorphisms were identified out of 614 infertile couples undergoing IVF-ICSI treatments. Group 1 included 20 couples in which only the male carried chromosomal polymorphisms; group 2 included 17 couples with female carriers only; group 3 included 19 infertile couples with normal karyotypes randomly selected as controls. A significantly lower fertilization rate was found in group 1 compared with groups 2 and 3 (56.68% in Group 1, 78.02% in group 2 and 71.74% in group 3; group 1 versus group 2, P < 0.001; group 1 versus group 3, P = 0.001; respectively). When stratified according to fertilization method, the fertilization rate in IVF cycles of group 1 was significantly lower than group 3 (50.00% in Group 1, 73.89% in Group 3, P < 0.001). Fertilization rates in ICSI cycles between groups 1 and 3 were not significantly different. This study suggests that male chromosomal polymorphisms adversely influence fertilization rates of IVF cycles. The use of ICSI may improve the success of infertility treatment by increasing the fertilization rate for men with chromosomal polymorphisms.

A preliminary study of the relationship between the long arm of the Y chromosome (Yqh+) and reproductive outcomes in IVF/ICSI-ET

OBJECTIVE

To compare the reproductive outcomes of Yqh+-carrying and control couples undergoing IVF/ICSI treatments.

STUDY DESIGN

Retrospective analysis of 72 Yqh+ carriers and 986 Yqh+ non-carriers undergoing their first cycle of ART in a single centre between August 2005 and May 2011.

RESULTS

Yqh+ carrying couples had significantly worse reproductive outcomes compared with control couples undergoing IVF treatment. There were a significantly higher cancellation rate (20.69% vs 7.9%; P<0.05; OR, 3.03; CI, 1.18-7.79) and a significant lower fertilisation rate (50.05% vs 66.01%; P<0.05; OR, 0.61; CI, 0.49-0.57), implantation rate (8.33% vs 20.87%; P<0.05; OR, 0.35; CI, 0.14-0.87), good quality embryo ratio (44.70% vs 57.89%; P<0.05; OR, 0.59; CI, 0.43-0.80) and clinical pregnancy rate (17.39% vs 39.59%; P<0.05; OR, 0.32; CI, 0.11-0.96) in Yqh+ group compared with control group undergoing IVF treatment. Yqh+ carrying couples had similar reproductive outcomes compared with control couples undergoing ICSI treatment.

CONCLUSIONS

The Y chromosome polymorphic variant Yqh+ most likely plays a role in infertility. Yqh+ couples with poor reproductive outcomes in IVF treatment can be advised to undergo ICSI to improve their reproductive results in the next cycle.

Y chromosome microdeletions in Mexican males of couples with idiopathic recurrent pregnancy loss

AIM

To analyze the presence of Y chromosome microdeletions in males of Mexican couples with idiopathic recurrent pregnancy losses (RPL).

METHODS

Seventy-one males from couples with RPL and 66 fertile males as controls were studied. DNA was isolated from peripheral lymphocytes and used to run multiplex polymerase chain reactions. Regions AZFa (sY84, sY86), AZFb (sY127, sY134) and AZFc (sY254, sY255) of the Y chromosome were analyzed according to valid guidelines recommended by the European Academy of Andrology and the European Molecular Genetics Quality Network. Also, the sequence tagged sites (STSs): DYS262 (sY67), DYS220 (sY129), DYF85S1 (sY150), DYF86S1 (sY152) and DYF87S1 (sY153) were included in order to analyze STSs previously reported as deleted. A power analysis to support our simple size was performed.

RESULTS

Results show an absence of Y chromosome microdeletions in males of couples with RPL and controls with an acceptable statistical power.

CONCLUSION

The study did not show an association of recurrent pregnancy loss and Y chromosome microdeletions in Mexican male partners. Based on the results, the study of Y chromosome microdeletions in couples with RPL is not considered clinically relevant.

DYZ1 copy number variation, Y chromosome polymorphism and early recurrent spontaneous abortion/early embryo growth arrest

OBJECTIVES

To find the association between recurrent spontaneous abortion (RSA)/early embryo growth arrest and Y chromosome polymorphism.

STUDY DESIGN

Peripheral blood samples of the male patients of big Y chromosome, small Y chromosome and other male patients whose partners suffered from unexplained RSA/early embryo growth arrest were collected. PCR and real-time fluorescent quantitative PCR were used to test the deletion and the copy number variation of DYZ1 region in Y chromosome of the patients. A total of 79 big Y chromosome patients (48 of whose partners suffered from RSA or early embryo growth arrest), 7 small Y chromosome patients, 106 other male patients whose partners had suffered from unexplained RSA or early embryo growth arrest, and 100 normal male controls were enrolled.

RESULTS

There was no fraction deletion of DYZ1 detected both in big Y patients and in normal men. Of RSA patients, 1 case showed deletion of 266bp from the gene locus 25-290bp, and 2 cases showed deletion of 773bp from 1347 to 2119bp. Of only 7 small Y chromosome patients, 2 cases showed deletion of 266bp from 25 to 290bp, and 4 cases showed deletion of 773bp from 1347 to 2119bp and 275bp from 3128 to 3420bp. The mean of DYZ1 copies was 3900 in normal control men; the mean in big Y patients was 5571, in RSA patients was 2655, and in small Y patients was 1059. All of the others were significantly different (P<0.01) compared with normal control men, which meant that DYZ1 copy number in normal control men was less than that of big Y chromosome patients, and was more than that of unexplained early RSA patients and small Y patients.

CONCLUSIONS

The integrity and copy number variation of DYZ1 are closely related to the Y chromosome length under microscope. The cause of RSA/early embryo growth arrest in some couples may be the increase (big Y patients) or decrease of DYZ1 copy number in the husbands' Y chromosome.