Diagnosis and treatment methods for recurrent miscarriage cases

Recurrent miscarriage is classically defined as three or more consecutive pregnancy losses. Established causes of recurrent miscarriage are antiphospholipid antibodies, uterine anomalies and abnormal chromosomes in either partner, particularly translocations. Embryonic aneuploidy is the most important cause of miscarriage before 10 weeks’ gestation. It can be speculated that about 51% of patients with a history of three miscarriages experienced these because of abnormal embryonic karyotypes. It is not necessary to give any medication for such cases caused by an abnormal embryonic karyotype. Psychological tender loving care might be the most important requirement to continue conceiving till live birth results.     

Can preimplantation genetic diagnosis overcome recurrent pregnancy failure?

PURPOSE OF REVIEW: Preimplantation genetic diagnosis is widely used for the detection of embryo aneuploidy before implantation, with the aim of avoiding miscarriage or pregnancy termination of an aneuploid fetus. The majority of first trimester miscarriages occur due to chromosomal imbalances. The aim of this review is to assess whether preimplantation genetic diagnosis can help women who suffer from recurrent pregnancy loss. RECENT FINDINGS: Several in-vitro fertilization clinics have employed preimplantation genetic diagnosis in women with recurrent pregnancy loss. Patients were classified into groups according to their age. Preimplantation genetic diagnosis was very successful in treating couples where one of the parents was a carrier of a balanced chromosomal abnormality such as a translocation. Similarly, recurrent pregnancy loss rate was reduced in women more than 35 years in age with a normal karyotype. On the other hand, in younger patients the beneficial effect of this procedure is debatable. In general, women with recurrent pregnancy loss produced more abnormal embryos than control groups. SUMMARY: Preimplantation genetic diagnosis can be beneficial for three major subgroups of patients with recurrent pregnancy loss: couples carrying chromosomal translocations; women more than 35 years of age; women of any age whose previous miscarriages were due to fetal aneuploidy. It is likely that the rate of miscarriage will be further reduced with the new advances in methods of performing preimplantation genetic diagnosis for more chromosomes.     

Pregnancy outcomes of reciprocal translocation carriers who have a history of repeated pregnancy loss

Cytogenetic investigation of 2,324 Japanese couples with repeated pregnancy loss revealed that 4.91% of couples (n = 114) had chromosome abnormalities including reciprocal translocation (n = 74), Robertsonian translocation (n = 23), and inversion (n = 10). Parental reciprocal translocation was a significant predictor of subsequent miscarriage (adjusted odds ratio: 3.6, 95% confidence interval: 1.8-7.1), and most of the miscarriages of the carrier couples were inevitable because of abnormal karyotypes, despite appropriate treatments.     

Outcome of preimplantation genetic diagnosis of translocations

Objective: To review 35 cases of preimplantation genetic diagnosis (PGD) of translocations with several methods, including telomeric probes.

Design: Retrospective study.

Setting: Clinical IVF laboratory.

Patient(s): Thirty-five couples with one partner carrying a chromosomal translocation.

Intervention(s): PGD of translocation after polar-body or embryo biopsy.

Main Outcome Measure(s): Pregnancy outcome.

Result(s): Several trends were observed. First, PGD can achieve a statistically significant reduction in spontaneous abortion, from 95% to 13%. Second, the chances of achieving pregnancy are correlated with 50% or more of the embryos being chromosomally normal. Third, patients with robertsonian translocations produced fewer abnormal gametes and more pregnancies than did patients with reciprocal translocations. Fourth, a new fluorescence in situ hybridization protocol for PGD of translocations, which involves applying telomeric probes, has proved adequately reliable with a 6% average error rate.

Conclusion(s): PGD of translocations achieves a statistically significant reduction in spontaneous abortion, both for polar-body and blastomere biopsy cases. Pregnancy outcome depended on the number of normal embryos available for transfer, with patients having <50% abnormal embryos achieving the most pregnancies. Because robertsonian translocations caused fewer abnormal embryos than reciprocal translocations, they also resulted in higher rates of implantation.     

Detection of balanced chromosome rearrangements in 445 couples with repeated abortion and cytogenetic prenatal testing in carriers

Cytogenetic studies were performed in 445 couples presenting because of repetitive abortion. The authors detected a balanced translocation in 19 (4.2%) of the couples, pericentric inversions in 8 (1.8%), and polymorphisms in 52 (11.4%). The results were compared with those obtained in a series of 600 consecutive normal liveborns. Significantly higher frequencies for translocations and polymorphisms were present in couples with repetitive abortion. No sex predominance in translocation carriers was observed, and reciprocal translocations were more common (16 of 19) than the robertsonian type (3 of 19). Contrary to other reports, all of the translocations and inversions were detected among couples without previous abnormal offspring. Cytogenetic prenatal testing in 17 pregnancies from a carrier parent showed that none of the fetuses had the unbalanced karyotype, 13 carried the balanced rearrangement, and 4 had a normal karyotype. Although a risk profile can be obtained for these couples, prenatal testing must be offered to avoid anxiety and unjustified pregnancy interruptions.     

Preimplantation genetic diagnosis by fluorescence in situ hybridization of reciprocal and Robertsonian translocations

ObjectiveThe presence of reciprocal and Robertsonian chromosomal rearrangement is often related to recurrent miscarriage. Using preimplantation genetic diagnosis, the abortion rate can be decreased. Cases treated at our center were reviewed.Materials and methodsA retrospective analysis for either Robertsonian or reciprocal translocations was performed on all completed cycles of preimplantation genetic diagnosis at our center since the first reported case in 2004 until the end of 2010. Day 3 embryo biopsies were carried out, and the biopsied cell was checked by fluorescent in situ hybridization using relevant informative probes. Embryos with a normal or balanced translocation karyotype were transferred on Day 4.ResultsThirty-eight preimplantation genetic diagnosis cycles involving 17 couples were completed. A total of 450 (82.6%) of the total oocytes were MII oocytes, and 158 (60.0%) of the two-pronuclei embryos were biopsied. In 41.4% of the fluorescent in situ hybridization analyses, the results were either normal or balanced. Embryos were transferred back after 21 cycles. Three babies were born from Robertsonian translocation carriers and another two from reciprocal translocation carriers. The miscarriage rate was 0%. Among the reciprocal translocation group, the live delivery rate was 8.3% per ovum pick-up cycle and 18.2% per embryo transfer cycle. Among the Robertsonian translocation group, the live delivery rate was 14.3% per ovum pick-up cycle and 20.0% per embryo transfer cycle.ConclusionThere is a trend whereby the outcome for Robertsonian translocation group carriers is better than that for reciprocal translocation group carriers. Aneuploidy screening may possibly be added in order to improve the outcome, especially for individuals with an advanced maternal age. The emergence of an array-based technology should help improve this type of analysis.     

Successful pregnancy outcomes after preimplantation genetic diagnosis (PGD) for carriers of chromosome translocations

Reciprocal translocations are found in about 1 in 500 people, whereas Robertsonian translocations occur with a prevalence of 1 in 1000. Balanced carriers of these rearrangements, although phenotypically normal, may present with infertility, recurrent miscarriage, or offspring with an abnormal phenotype after segregation of the translocation at meiosis. Once the translocation has been identified, prenatal diagnosis can be offered, followed by termination of pregnancies with chromosome imbalance. Couples who have suffered repeated miscarriage or those who have undergone termination of pregnancy as a result of the translocation carrier status of one partner are looking increasingly to preimplantation genetic diagnosis (PGD) as a way of achieving a normal pregnancy. Similarly, infertile couples in which one partner is a translocation carrier may request PGD to ensure transfer of normal embryos after in vitro fertilization. Translocation PGD has been applied successfully in several centres worldwide and should now be considered as a realistic treatment option for translocation carriers who do not wish to trust to luck for a successful natural outcome.     

Successful pregnancy outcomes after preimplantation genetic diagnosis (PGD) for carriers of chromosome translocations

Reciprocal translocations are found in about 1 in 500 people, whereas Robertsonian translocations occur with a prevalence of 1 in 1000. Balanced carriers of these rearrangements, although phenotypically normal, may present with infertility, recurrent miscarriage, or offspring with an abnormal phenotype after segregation of the translocation at meiosis. Once the translocation has been identified, prenatal diagnosis can be offered, followed by termination of pregnancies with chromosome imbalance. Couples who have suffered repeated miscarriage or those who have undergone termination of pregnancy as a result of the translocation carrier status of one partner are looking increasingly to preimplantation genetic diagnosis (PGD) as a way of achieving a normal pregnancy. Similarly, infertile couples in which one partner is a translocation carrier may request PGD to ensure transfer of normal embryos after in vitro fertilization. Translocation PGD has been applied successfully in several centres worldwide and should now be considered as a realistic treatment option for translocation carriers who do not wish to trust to luck for a successful natural outcome.     

Embryonic karyotype of abortuses in relation to the number of previous miscarriages

OBJECTIVE: To examine the frequency of chromosomal abnormalities in products of conception from patients with recurrent miscarriages in relation to the number of previous miscarriages. DESIGN: Retrospective analysis. SETTING: Nagoya City University Medical Hospital. PATIENT(S): A total of 1,309 women with a history of 2-20 consecutive first-trimester abortions. INTERVENTION(S): Chromosomal analysis performed on products of conception with use of a standard G-banding technique. MAIN OUTCOME MEASURE(S): The frequencies of abnormal and normal embryonic karyotypes for each number of previous abortions were studied. The subsequent pregnancy outcome of patients whose previous miscarriages were karyotyped were studied along with the predictive value of karyotyping of previous miscarriages for subsequent miscarriages. RESULT(S): The miscarriage rate increased with the number of previous spontaneous abortions. The frequency of abnormal embryonic karyotypes significantly decreased and that of normal embryonic karyotypes significantly increased with the number of previous abortions. Among 71 patients whose embryonic karyotypes were normal, 44 aborted subsequently, and 23 of 60 patients whose embryonic karyotypes were abnormal aborted subsequently. Patients with a previous normal embryonic karyotype aborted more frequently than those with an abnormal karyotype. CONCLUSION(S): The frequency of normal embryonic karyotypes significantly increases with the number of previous abortions, and a normal karyotype in a previous pregnancy is a predictor of subsequent miscarriage.     

Chromosomal aberrations in 2000 couples of Indian ethnicity with reproductive failure

Constitutional chromosomal aberrations contribute to infertility and repeated miscarriage leading to reproductive failure in couples. These aberrations may show no obvious clinical manifestations and remain undetected across multiple generations. However, infertility or recurrent spontaneous pregnancy loss, and/or genotypic/phenotypic aberrations may be manifested in the progeny during gametogenesis. The current study was a retrospective analysis to examine the chromosomal aberrations and prevalence in 2000 couples of Indian ethnicity with reproductive failure. Cytogenetic analysis via conventional G-band karyotyping analysis was carried out on phytohaemagglutinin stimulated peripheral blood lymphocytes, cultured in RPMI1640 medium. The chromosomes were enumerated as per International System for Human Cytogenetic Nomenclature at 500–550 band resolution, and recorded in the screening sheets. Chromosomal aberrations were detected in a total of 110 (2.78%) couples, with structural chromosomal aberrations in 88 cases including reciprocal translocations in 56 cases, Robertsonian translocations in 16 cases, inversions in eight cases, deletions in three cases, derivative chromosomes in five cases and numerical chromosome aberrations in 23 cases. The study emphasizes the importance of cytogenetic work up in both the partners associated with a history of reproductive failure. Genetic counselling with an option of prenatal diagnosis should be offered to couples with chromosomal aberrations.Alteration in the number or structure of chromosomes is associated with adverse obstetric outcome in the form of infertility or recurrent miscarriages. Most of these aberrations are balanced and hence, the person does not manifest any obvious clinical signs and symptoms. However, because of the formation of abnormal gametes (i.e. the eggs and sperm), these chromosomal aberrations result in infertility and recurrent spontaneous pregnancy losses. In the present study, we studied 2000 couples of Indian ethnicity with reproductive failure. Karyotyping was done on the blood sample of these couples using standard protocols. Chromosomal aberrations were detected in a total of 110 (2.78%) couples with structural chromosomal aberrations in 88 cases including reciprocal translocations in 56 cases, Robertsonian translocations in 16 cases, inversions in eight cases, deletions in three cases, derivative chromosomes in five cases and numerical chromosome aberrations in 23 cases. Thus, our study emphasizes the importance of cytogenetic work up in both the associated partners with history of reproductive failure which would help in better patient counselling and management.     

Karyotype of the abortus in recurrent miscarriage

OBJECTIVE: To assess the chromosomal aberrations in the abortus in recurrent miscarriage and the live birth rate after a euploid or aneuploid miscarriage. DESIGN: Retrospective analysis. SETTING: Tertiary referral unit in university hospital. PATIENT(S): One hundred sixty-seven patients with 3 to 16 miscarriages before 20 weeks. INTERVENTION(S): Material collected at curettage from 167 abortuses was analyzed by standard G-banding techniques. MAIN OUTCOME MEASURE(S): The incidence of aberrations and the outcome of the subsequent pregnancy were assessed according to the embryonic karyotype. RESULT(S): In this study 125 specimens were successfully karyotyped. Of these, 29% (36 of 125) had chromosome aberrations; 94% of the aberrations were aneuploidy, and 6% were structural. The most prevalent anomalies were chromosome 16, 18, and 21 trisomies, triploidy, and monosomy X. After an aneuploid miscarriage, there was a 68% subsequent live birth rate (13 of 19) compared to the 41% (16 of 39) rate after a euploid abortion. CONCLUSION(S): The low (29%) incidence of aberrations indicates that alternative mechanisms may be responsible for the majority of recurrent miscarriages. These figures provide a basis for assessing the efficacy of therapy for recurrent miscarriage. If further studies confirm that patients with karyotypically abnormal fetuses have a good prognosis, an informed decision can be made as to whether further investigations and treatment should be undertaken.     

Chromosomal analysis in Japanese couples with repeated spontaneous abortions

Balanced chromosome rearrangements have been found at an increased frequency in couples with pregnancy wastage, especially recurrent spontaneous abortions, compared with the general population. In the present study, chromosomal analysis of peripheral blood cells, as one of the routine examinations of patients with repeated reproductive wastage, was performed on both partners of 639 Japanese couples. Among the 639 couples, 32 major chromosomal anomalies (5.0%) and 23 minor chromosomal variants (3.6%) were found. Both partners of one couple had an abnormal karyotype. The 32 major anomalies consisted of 19 reciprocal translocations, 9 Robertsonian translocations, one large inversion, two triple-X females, and one Turner mosaicism. The 23 minor variants included 15 cases of pericentric inversion of chromosome 9. The total number of pregnancies in the 54 couples with chromosomal anomalies was 181, but they resulted in only 18 normal liveborn neonates, indicating a 90.1% abortion rate. The present statistical study indicates that major chromosomal anomalies seem to be involved in repeated reproductive wastage.     

染色体平衡易位携带者妊娠风险及妊娠结局的研究

目的 探讨染色体平衡易位携带者的妊娠风险及其妊娠结局.方法 194例染色体平衡易位携带者,根据平衡易位种类分成相互易位（135例）、非同源罗伯逊易位（52例）、同源罗伯逊易位（7例）3组.调查携带者生育史并随访诊断平衡易位后的妊娠情况,比较各组自然流产、先天缺陷及正常（或）平衡易位后代概率.结果 （1）194对夫妇共妊娠503例次,其中自然流产411例次（81.7%,411/503）;产前诊断胎儿异常而终止妊娠16例次（3.2%,16/503）;活产缺陷儿36例次（7.2%,36/503）;正常（或）平衡易位后代40例次（8.0%,40/503）.（2）相互易位、非同源罗伯逊易位、同源罗伯逊易位3组,活产缺陷儿比率分别为5.7%（20/350）、10.9%（14/128）、8.0%（2/25）,3组间相互比较,差异有统计学意义（P＜0.05）;3组正常（或）平衡易位后代比率分别为6.6%（23/350）、13.3%（17/128）、0,3组间相互比较,差异有统计学意义（P＜0.05）;而3组自然流产及产前诊断胎儿异常终止妊娠比率比较,差异无统计学意义（P＞0.05）.（3）52例次先天缺陷中活产36例次（69%）,经产前诊断确诊后引产16例次（31%）.27例次先天缺陷获得细胞遗传学诊断,唐氏综合征发生率为59%（16/27）.（4）相互易位组和非同源罗伯逊易位组共有39对夫妇得到40个正常（或）平衡易位后代,同源罗伯逊易位组无正常（或）平衡易位后代.40个正常（或）平衡易位后代中26个获得产前细胞遗传学诊断,正常核型6个（23%）,平衡易位核型20个（77%）.结论 染色体平衡易位携带者自然妊娠风险大,尤其同源罗伯逊易位携带者难以获得染色体正常（或）平衡易位的后代.     

Data on Families of Chromosome Translocation Carriers Ascertained Because of Habitual Spontaneous Abortion

Cytogenetic studies were performed on 1,180 individuals--490 couples + 200 females presenting with habitual spontaneous abortion (HSA). These revealed 24 abnormal results (2.03%)--15 were apparently balanced reciprocal translocations and 9 were Robertsonian translocations. Of 97 pregnancies among the translocation carriers, there were 10 living children and 87 pregnancy losses--a loss rate of 89.7%. There were 11 familial translocations. In 10 familial cases with a full family tree, there were 27 spontaneous abortions and 64 livebirths among the 30 adult translocation carrier relatives--a loss rate of 29.6%. This is twice the risk found in the general population but not as high as in the probands, who had 6 times the abortion rate in the general population. Mechanisms are suggested for this difference. The subsequent pregnancy history of 12 index translocation couples showed an apparently improved pregnancy outcome with 13 further fetal losses and 13 living children, over a follow-up time per patient ranging from 1-5.5 years. However, when the pregnancy losses at ascertainment were combined with postascertainment losses, the overall rate of pregnancy loss remained the same.     

Preimplantation genetic diagnosis significantly improves the pregnancy outcome of translocation carriers with a history of recurrent miscarriage and unsuccessful pregnancies

Preimplantation genetic diagnosis (PGD) for translocations has been shown to significantly reduce the risk of recurrent miscarriage, but because the majority of embryos produced are unbalanced, pregnancy rate is relatively low since 20% or more cycles have no normal or balanced embryos to transfer. The purpose of this study was to evaluate whether PGD could improve pregnancy outcome in translocation carriers with a history of two or more consecutive miscarriages and no live births. PGD for translocations was offered to translocation carriers with two or more previous miscarriages (average 3.5) and no live births (0/117 pregnancies) using a combination of distal and proximal probes to the breakpoints. After PGD, only 18.3% of embryos were normal or balanced. Only 5.3% of pregnancies were lost after PGD compared with 100% before PGD (P < 0.001). The cumulative pregnancy rate was 57.6% and the cumulative ongoing pregnancy rate was 54.5% in the short period of time of 1.24 IVF cycles, or 46.3% and 43.9% respectively per cycle. In conclusion, PGD significantly reduced losses and increased the number of viable pregnancies (P < 0.001). IVF plus PGD are a faster method of conceiving a live child than natural conception, at least for translocation carriers with recurrent miscarriages and no previous live births.     

Assessment of male factor involved in recurrent pregnancy loss: A preliminary study

This study was conducted to assess the male factor as standard sperm parameters, age and chromosome abnormalities from men whose partners had a history of recurrent pregnancy loss (RPL).A 2?years retrospective study was carried out in 149 couples with 2 or more miscarriages. They referred to as for genetic counseling in the laboratory of histology housed in a Faculty of Medicine of Sfax, with genetic laboratories.Chromosomal analysis was performed using RHG banding in peripheral blood and semen samples were analyzed from men according to World Health Organization guidelines.67 men were selected of a total of 149 couples whose partners were healthy and with normal karyotype. About them, the mean age was 33?years [from 22 to 53], and altered semen parameters were detected in more than 25%.Abnormal karyotype was detected in 4 men with an overall incidence of 5.97%. The commonest abnormalities appear to be reciprocal translocation.So, this data emphasizes the importance of assessment of male factor in addition to standard female factors for evaluating the risk for RPL.     

2178对自然流产史夫妇染色体分析

目的:分析自然流产史夫妇外周血染色体异常核型的种类及其在男女性中的分布特点。方法:检测2178对自然流产史夫妇外周血淋巴细胞染色体核型,分析比较染色体变异的种类、发生率及其在男、女性中的分布差异。结果:2178对(4356例)自然流产史夫妇中发现染色体异常539例(12.37%),其中男266例,女273例。染色体结构异常87例,其中相互易位最多见为58例(66.7%,58/87),有27例为世界首报染色体结构异常核型。其次为罗伯逊易位13例,倒位6例,插入、缺失等其他异常核型10例。染色体数目异常8例,包括2例标记染色体、1例XYY及5例不同类型的X染色体非整倍体嵌合。多态性改变444例中,D/G组染色体随体区变异最为多见,共271例(61.04%,271/444)。结论:自然流产史夫妇外周血染色体异常均有发生,男女性发生率并无明显差异,染色体异常以相互易位为主。染色体多态性发生率较高,对以自然流产史就诊的夫妇,有必要同时进行染色体检查,有助于病因的分析与诊断,并为临床咨询及后续生殖干预提供依据。     

Habitueller Abort – genetische Ursachen

Genetic factors play an etiologic role in sporadic and recurrent miscarriage. Fetal chromosomal anomalies are the main cause of sporadic miscarriages, whereas in recurrent miscarriages, the rate of fetal chromosomal anomalies is inversely correlated to the number of miscarriages. An abnormal karyotype is present in 3–5% of women with a diagnosis of recurrent miscarriage and their partners. Specific polymorphisms are also associated with an increased risk for recurrent miscarriage. Genetic thrombophilia conferred by carrying the factor V Leiden polymorphism is of clinical relevance for women with recurrent miscarriage due to possible treatment with heparin. Another genetic factor associated with recurrent miscarriage is skewed X-chromosome inactivation, defined as a selective inactivation of paternal or maternal X chromosomes. In addition, androgenetic anomalies such as sperm aneuploidy and sperm DNA fragmentation have been described as etiologic factors in recurrent miscarriage.     

Antiphospholipid antibodies and the investigation of recurrent miscarriage

Recurrent miscarriage (three or more consecutive miscarriages) affects 1% of the female population and this causes severe psychological morbidity in both the sufferer and their partner. For many years the aetiology of recurrent miscarriage in the majority of cases has remained unclear. Treatment regiments to improve pregnancy outcome were based on poorly-designed studies, often without control cohorts, which have subsequently been shown to be of no proven benefit. Over the past 15 years accumulating evidence has implicated the presence of antiphospholipid antibodies (APAbs) in the aetiology of recurrent miscarriage. APAbs can be found in 15% of the recurrent miscarriage population, and are associated with first and second-trimester miscarriages as well as other obstetric complications. Aspirin and subcutaneous heparin administration are of clinically-proven benefit in lowering the miscarriage rate in women with this condition. Maternal side effects of aspirin and heparin are rare but include thrombocytopenia and osteoporosis. No direct teratogenic effects of aspirin and heparin have been demonstrated but pregnancies complicated by APAbs need to be monitored closely for evidence of pre-eclampsia and intrauterine growth restriction.     

Thyroid antibody titer and avidity in patients with recurrent miscarriage

OBJECTIVE: To determine whether the titer and avidity of the thyroid peroxidase antibody differs between pregnant women in their first trimester who have a history of recurrent miscarriage and whose pregnancies continue to term and those whose pregnancies fail again later in the first trimester. DESIGN: Controlled clinical study. SETTING: Healthy volunteers in an academic research environment. PATIENT(S): Pregnant women in their first trimester who had a history of recurrent miscarriage (> or = 3 miscarriages) and who were known to be positive for the thyroid peroxidase antibody. INTERVENTION(S): None of the patients received any medication. MAIN OUTCOME MEASURE(S): Thyroid peroxidase antibody titer and avidity (i.e., the net binding strength between antibody and antigen). RESULT(S): At the time of presentation, thyroid peroxidase antibody titer and avidity was significantly higher in those women who later miscarried compared with those whose pregnancies continued. In those whose pregnancies continued to term, titer and avidity declined as the pregnancy progressed. CONCLUSION(S): Autoimmunity plays a role in recurrent miscarriage. Among a group of patients who had had recurrent miscarriages, there appeared to be differences in the humoral response to the pregnancy between those whose pregnancies continued to term and those whose pregnancies failed again.