Influence of forkhead box protein 3 gene polymorphisms in recurrent pregnancy loss: A meta-analysis.

BACKGROUND: Treg cells play an important role in development of tolerance in maternal immune system against the semi-allogenic embryo. Human forkhead box protein 3 (FOXP3) gene, is the major transcription factor responsible for the regulation of Treg function during pregnancy. Single nucleotide polymorphisms (SNPs) of FOXP3 gene have been reported as a risk factor for Recurrent Pregnancy Loss (RPL), however, results from previous studies are inconsistent. METHODOLOGY: We have collected data from different studies to investigate the overall association of FOXP3 SNPs with risk of RPL. PubMed, Google Scholar, Elsevier, and Cochrane databases were searched to identify eligible studies. Odds Ratio (OR) and 95 % Confidence Interval (CI), calculated via fixed effect or random effect models, were used to evaluate strength of association. This meta-analysis included 11 studies (1383 RPL cases and 1413 controls) of 6 SNPs: rs3761548 A/C, rs2232365 A/G, rs2294021 T/C, 2280883 T/C, rs5902434del/ATT and rs141704699C/T, with ≥2 studies per SNPs and at least 1 significant result. RESULTS: We observed that FOXP3 polymorphism was predominantly present in Asian women with history of RPL. rs2232365 A/G, rs3761548 A/C, rs2294021 T/C, rs2280883 T/C and rs5902434del/ATT polymorphisms were significantly associated with risk of RPL in Indian population. Further, among the most commonly seen polymorphism, rs3761548 A/C was significantly associated with risk of RPL in women from Kazakhstan, China and Gaza, Palestine; rs2232365 A/G in populations of Kazakhstan, Egypt, Iran and Gaza, Palestine. Results of this study indicates that FOXP3 polymorphism is significantly associated with risk of RPL, especially in Asians.

Association of VEGF and p53 Polymorphisms and Spiral Artery Remodeling in Recurrent Pregnancy Loss: A Systematic Review and Meta-Analysis.

Many studies have reported the association of VEGF-1154G/A, VEGF 936C/T, and p53 Arg72Pro polymorphisms with recurrent pregnancy loss (RPL), but the outcomes are inconsistent. We have used a meta-analysis to associate these polymorphisms with RPL, having the spiral artery remodeling as a major risk factor. The studies were identified from three different reputed databases, namely ScienceDirect, PubMed/Medline, and Scopus. The eligible studies of VEGF-1154G/A, VEGF 936C/T, and p53Arg72Pro polymorphisms associated with the RPL were selected for the analysis. They were segregated into three different ethnic groups as Asians, Caucasians, and mixed population. For the analysis, the overall prevalence, odds ratio, risk ratio, relative risk ratio, and p-values were calculated. A total of 3,241 RPL cases and 3,205 healthy controls from 21 different case-control studies were analyzed. RPL was highly prevalent in the mixed population with VEGF-1154G/A and p53 Arg72Pro polymorphisms (70.04 and 66.46%, respectively) and in the Asian population with VEGF 936C/T polymorphism (53.58%). The homozygous recessive genotypes of VEGF and p53 exhibited significant association between the respective polymorphisms and RPL along with the increased risk of outcome. The current analysis conclusively reports the geographic distribution of the different genetic polymorphisms which shows high association with the progression of RPL. Understanding the spectrum of polymorphisms on different populations with the spiral artery remodeling as a risk factor encloses the importance of the vasculature during the pregnancy.

The association between 5, 10 - methylenetetrahydrofolate reductase and the risk of unexplained recurrent pregnancy loss in China: A Meta-analysis.

BACKGROUD: To analyze the correlation between gene polymorphisms of 5,10- methylenetetrahydrofolate reductase (MTHFR) and risk of unexplained recurrent pregnancy loss (URPL) in Chinese women. METHODS: Eligible studies were searched in Pubmed, Embase, Web of Science, Wanfang, and China National Knowledge Infrastructure (CNKI) databases. Established inclusion criteria were used to screening articles, subsequently evaluate the quality of the included studies, Stata 16.0 PM and RevMan 5.3 software were conducted for meta-analysis. The pooled odds ratio (OR) with 95% confidence interval (CI) was determined to assess the relationship between MTHFR and risk of URPL in Chinese women. RESULTS: For MTHFR C677T, fifty studies were included, involving 6677 URPL cases and 8111 controls. The overall results showed that MTHFR C677T was significantly correlated with URPL risk, especially in the homozygous model (TT vs CC; OR 3.06; 95% CI 2.56-3.66). For MTHFR A1298C, twenty-first studies were included, involving 3439 URPL cases and 3155 controls. The results showed that MTHFR A1298C was also significantly correlated with URPL risk in recessive (CC vs AC + AA; OR 1.55; 95% CI 1.25-1.93) and homozygous (CC vs AA; OR 1.53; 95% CI 1.22-1.91) models. In addition, sub-group results showed that no significant difference between north and south China populations in the MTHFR gene polymorphisms and URPL risk. Of note, the patients carrying MTHFR C677T and MTHFR A1298C joint mutants had no synergistic effect (OR 2.71; 95% CI 0.84-8.70) on the occurrence of URPL compared with the wild-type homozygous genotype (MTHFR 677CC/ MTHFR 1298AA). CONCLUSION: Studies included in this meta-analysis suggested that MTHFR 677T allele and 677TT genotype and MTHFR 1298CC genotype were both associated with URPL; testing MTHFR C677T gene polymorphism was a more appropriate target compared with other mutations in the prediction of URPL.

Male sperm quality and risk of recurrent spontaneous abortion in Chinese couples: A systematic review and meta-analysis.

OBJECTIVE: To assess the association of conventional semen parameters and sperm DNA fragmentation with risk of recurrent spontaneous abortion (RSA). DESIGN: Systematic review and meta-analysis. SETTING: Not applicable. PATIENTS: Total 1,690 male partners of women with RSA, and 1,337 male partners of fertile control women. INTERVENTIONS: Case-control or cohort studies were determined by searching PubMed, Google Scholar, Cochrane Libraries, China Biology Medicine disc, Chinese Scientific Journals Fulltext Database, China National Knowledge Infrastructure, and Wanfang Database. RSA was defined as two or more previous pregnancy losses. The fertile women refer to the reproductive women who have had at least a normal pregnancy history and no history of abortion. MAIN OUTCOME MEASURES: This study included eight outcome measures: semen volume(ml), semen pH value, sperm density(106/ml), sperm viability (%), sperm progressive motility rate (%), normal sperm morphology rate (%), sperm deformity rate(%), sperm DNA fragmentation index (DFI) (%). The summary measures were reported as standardized mean difference (SMD) with 95% confidence interval (CI). RESULTS: Finally, twenty-four studies were included for analysis. Overall, male partners of women with RSA had a significantly lower level of sperm density (SMD = -0.53, 95%CI: - 0.75 to -0.30), sperm viability (SMD = -1.03, 95%CI: - 1.52 to -0.54), sperm progressive motility rate (SMD = -0.76, 95%CI:-1.06 - -0.46), and normal sperm morphology rate (SMD =  -0.56, 95%CI: - 0.99 to -0.12), and had a significantly higher rate of sperm deformity rate (SMD = 1.29, 95%CI: 0.60 - 1.97), and sperm DFI (SMD = 1.60, 95%CI: 1.04 to 2.17), when compared with the reference group. However, there were no statistically significant differences for semen volume (SMD = -0.03, 95%CI: -0.14 - 0.08) and semen pH value (SMD =  -0.23, 95% CI: -0.50 to 0.05) among 2 groups. CONCLUSIONS: The results of this analysis support an association of sperm density, sperm viability, sperm progressive motility rate, normal sperm morphology rate, sperm deformity rate, as well as sperm DFI with RSA. However, given the significant heterogeneity between studies and the lack of more detailed data on the subjects, further large-scale prospective studies are needed.

Associations between tumor necrosis factor-α and interleukin-6 polymorphisms and unexplained recurrent spontaneous abortion risk: A meta-analysis.

To evaluate the associations between Tumor necrosis factor-α (TNF-α)(-238G>A) and Interleukin-6 (IL-6)(-174G>C) polymorphism and risk of unexplained recurrent spontaneous abortion (URSA).Correlated case-control studies were collected by computer retrieval. A meta-analysis was conducted by Stata 12.0 software to analysis the strength of association between polymorphism of TNF-α -238G>A and IL-6 -174G>C and URSA.Twenty-one articles with twenty-two studies were included, of which 12 and 10 studies were respectively related to mutation of TNF-α -238G>A, IL-6 -174G>C and URSA. The integrated results showed that the TNF-α-238G>A gene mutation was significantly correlated with the risk of URSA under homozygote model (AA vs GG;OR 1.533,95% CI 1.022-2.301) and recessive model (AA vs GG+AG;OR 1.571,95%CI 1.050-2.350)(P < .05). There was no association between URSA and TNF-α -238G>A under heterozygote model (AG vs GG;OR 0.963,95% CI 0.816-1.137), dominant model (AA+AG vs GG; OR 1.031,95%CI 0.880-1.209) and additive model (A vs G;OR 1.046,95%CI 0.909-1.203)(P > .05). The results of subgroup analysis based on ethnicity showed that -238G>A was significantly correlated with the risk of URSA in Asians under all gene models except for heterozygote model (AG vs GG; OR 1.129,95% CI 0.857-1.487) (P < .05). In Caucasians, it was dominant model (AA+AG vs GG; OR 1.430,95%CI 1.040-1.965) (P < .05) rather than others that showed relationship with URSA. From the integrated results, association was manifested between -174G>C and URSA under all gene models (P < .05) except for recessive model (CC vs GG+CG, OR 1.166, 95%CI 0.938-1.449) (P > .05), which is identical to subgroup analysis based on ethnicity.It is of great guiding significance for screening out and preventing URSA among high-risk women to test on TNF-α -238G>A and IL-6 -174G>C under gene models mentioned above which are highly associated with the risk of URSA, which can act as biological markers for URSA.

Association of genetic polymorphisms in VEGF -460, -7 and -583 and hematocrit level with the development of idiopathic recurrent pregnancy loss and a meta-analysis.

BACKGROUND: The present study was performed to investigate whether genetic variants of VEGF are associated with recurrent pregnancy loss (RPL) in Korean women and to provide insight into the role of VEGF in the pathogenesis of RPL development. METHODS: A cohort of 384 women with idiopathic RPL with a history of two or more uxexplained consecutive early pregnancy losses and 236 control women were recruited from an infertility center of university-teaching hospital in Korea between March 1999 and February 2010. We examined three VEGF polymorphisms (rs833061, rs3025020 and rs25648). Genotyping was assessed by polymerase chain reaction (PCR)-restriction fragment length polymorphism analyses (rs3025020) or real-time PCR (rs833061, rs25648). RESULTS: There was no statistically significant difference in frequency of each three VEGF polymorphic loci between the control and RPL groups. Allele combinations of VEGF rs3025020/rs833061 TT/TC and TT/TC + CC genotypes were associated with an increased frequency of RPL development [odds ratio (OR) = 3.525, 95% confidence interval (CI) = 1.154-10.767, p = 0.027 and OR = 3.815, 95% CI = 1.256-11.588, p = 0.018, respectively]. Haplotype analysis revealed that two allele combinations (rs833061/rs3025020 C-T and rs25648/rs3025020 T-T) were associated with an increased prevalence of RPL (OR = 2.548, 95% CI = 1.502-4.320, p = 0.0004 and OR = 16.50, 95% CI = 0.976-278.8, p = 0.003, respectively). Allele combinations and haplotypes of rs3025020/rs833061 were associated with maternal blood hematocrit (HCT) levels in the RPL group (p = 0.048 and 0.006, respectively). CONCLUSIONS: The VEGF rs833061/rs3025020 genotype allele was related to the development of RPL and was also associated with maternal blood HCT levels in RPL patients. However, further studies are needed to clarify the exact mechanism of how VEGF and HCT are involved in RPL development.

The association of IL-33 and Foxp3 gene polymorphisms with recurrent pregnancy loss in Egyptian women.

Deregulated immunity is one of the most important factors implicated in recurrent pregnancy loss (RPL). The possible role of interleukin-33 (IL-33) and forkhead/winged helix transcription factor (Foxp3) in RPL have not been fully investigated. We aimed to evaluate IL-33 rs1929992 and Foxp3 rs2232365 single nucleotide polymorphisms (SNPs) and their serum levels in Egyptian RPL females. Blood samples were collected from 142 RPL patients and 123 women as healthy controls. IL-33 rs1929992 SNP was determined by polymerase chain reaction restriction fragment length polymorphism and Foxp3 rs2232365 SNP was determined using allele specific polymerase chain reaction. The serum IL-33 and Foxp3 levels were measured by enzyme linked immunosorbent assay. Foxp3 rs2232365 SNP showed statistically significant association with RPL. The risk of RPL was significantly higher in women carrying Foxp3 G allele than those carrying A allele. Lower serum levels of Foxp3 and IL-33 were observed in RPL patients than controls (P < 0.001). Foxp3 serum levels were much lower in carriers of G allele than those carrying A allele in all studied groups. Foxp3 rs2232365 SNP could be considered as a risk factor for RPL. The lowered serum levels of IL-33 and Foxp3 in RPL patients suggested that they might have an important role in the pathogenesis of the disease. Therefore, we hypothesized that Foxp3 polymorphisms may be important in RPL pathogenesis.

Polymorphisms of F2, PROC, PROZ, and F13A1 Genes are Associated With Recurrent Spontaneous Abortion in Chinese Han Women.

Mutations of hemostasis/coagulation-related genes have been speculated to cause recurrent spontaneous abortion (RSA). This study investigated the genetic association between the polymorphisms of factor V (F5), factor II (F2), antithrombin (SERPINC1), protein C (PROC), protein S (PROS1), protein Z (PROZ), factor XIII (F13A1), and carboxypeptidase B2 (CPB2) genes and RSA. The 426 patients with RSA and 444 controls were recruited in this study, and single-nucleotide polymorphisms (SNPs) were analyzed by using SNPscan technology. Genotype and allele frequencies of rs3136520 in F2, rs3024731 in PROZ, and rs1050782 in F13A1 showed statistically significant differences between the 2 groups. TT genotype of rs3136520 ( P = .031, odds ratio [OR] = 0.986, 95% confidence interval [CI] = 0.976-0.997) and AA genotype of rs2069906 in PROC ( P = .021, OR = 0.114, 95% CI = 0.014-0.902) in their recessive models and AG + GG variants of rs1050782 ( P = .007, OR = 0.681, 95% CI = 0.516-0.899) in the dominant model might be associated with the reduced risk of RSA. AT + TT variants of rs3024731 ( P = .010, OR = 1.479, 95% CI = 1.098-1.994) may increase disease susceptibility in dominant model. Haplotype analysis of rs3024731 and rs3024735 in PROZ displayed that the AA and TG haplotype were inclined to decrease and increase the risk of RSA, respectively. These results suggested that rs3136520, rs2069906, rs3024731, and rs1050782 may have a significant association with the genetic susceptibility of RSA in Chinese Han women.

Recurrent Pregnancy Loss and Cardiovascular Disease Mortality in Japanese Women: A Population-Based, Prospective Cohort Study.

BACKGROUND: This study aimed to examine the association between recurrent pregnancy loss and the risk of cardiovascular disease mortality. METHODS: We identified 54,652 women who were pregnant during the Japan Collaborative Cohort Study. These women were 40-79 years at the date of cohort entry between 1988 and 1990. Participants received municipal health screening examinations and completed self-administered questionnaires. The cause of death was confirmed by annual or biannual follow-up surveys for a median of 18 years. The exposure was the number of pregnancy loss. The outcome was mortality from total cardiovascular disease and its subtypes according to the International Classification of Diseases, 10th Revision. Adjustment variables included age, number of deliveries, education, body mass index, physical activity, smoking status, and drinking status. Kaplan-Meier survival curves were used to estimate the cumulative mortality. RESULTS: The number of pregnancy loss tended to be inversely associated with the risk of mortality from total stroke, intracerebral hemorrhage, and total cardiovascular disease. The multivariable hazard ratio of total cardiovascular disease for ≥2 pregnancy losses versus no pregnancy loss was .84 (95% confidence interval, .74-0.95). A 2-fold excess risk of mortality from ischemic stroke associated with ≥2 pregnancy losses was observed in women aged 40-59 years, with a multivariable hazard ratio of 2.19 (95% confidence interval, 1.06-4.49), but not in older women. CONCLUSIONS: Recurrentpregnancy loss tends to be associated with a lower risk of mortality from cardiovascular disease at 40-79 years. Younger women have an excess risk of ischemic stroke mortality associated with recurrent pregnancy loss.

Rs4265085 in GPER1 gene increases the risk for unexplained recurrent spontaneous abortion in Dai and Bai ethnic groups in China.

Oestrogen receptors are implicated in the pathogenesis of recurrent spontaneous abortion (RSA). Non-genomic oestrogen responses can be mediated by GPER. The prevalence of polymorphisms in GPER1 gene in RSA was assessed in 747 Chinese women from Yunnan province (171 Bai, 258 Chinese Han, 234 Dai, 33 Achang and 51 Jingpo patients). Snapshot technology was used for genotyping the polymorphisms of the GPER1 gene. The rs4265085G was significantly increased in the Dai and Bai groups versus controls (Dai: P < 0.0001, Padj < 0.0001, OR 95% CI 2.34 [1.79 to 3.05]; Bai: P = 0.0004, Padj = 0.0012, OR 95% CI 1.71 [1.27 to 2.31]); recessive model of rs4265085 in the Dai (P = 0.003, Padj = 0.009, OR 95% CI 2.71 [1.38 to 5.30]); Bai (P < 0.0001, Padj < 0.0001, OR 95% CI 3.37 [1.93 to 5.91]). Haplotype frequencies containing rs10269151G-rs4265085G-rs11544331C were separately significantly different in Dai and Bai ethnic groups (Dai: P = 0.0002, Padj = 0.001, OR 95% CI = 2.12 [1.43 to 3.17]; Bai: P = 0.005, Padj = 0.025, OR 95% CI = 1.82 [1.18 to 2.78]) compared with controls. The intron variant rs4265085 may confer risk for RSA in Dai and Bai ethnic groups.

Genetic Variation of Methylenetetrahydrofolate Reductase (MTHFR) and Thymidylate Synthase (TS) Genes Is Associated with Idiopathic Recurrent Implantation Failure.

The one-carbon metabolism pathway disorder was important role in successful pregnancy. The MTHFR and TS protein were crucial factor in one-carbon metabolism. To investigate the association between recurrent implantation failure (RIF) and enzymes in the one-carbon metabolism pathway. A total of 120 women diagnosed with RIF and 125 control subjects were genotyped for MTHFR 677C>T, 1298A>C, TSER 2R/3R and TS 1494del/ins by a polymerase chain reaction-restriction fragment length polymorphism assay. According to the gene-gene combination analysis, the MTHFR 677/MTHFR 1298 (TT/AA) and MTHFR 677/TS 1494 (TT/6bp6bp) genetic combinations were associated with relatively higher risks [adjusted odds ratio (AOR), 2.764; 95% CI, 1.065-7.174; P = 0.037 and AOR, 3.186; 95% CI, 1.241-8.178; P = 0.016] in RIF patients compared to the CC/AA (MTHFR 677/MTHFR 1298) and TT/6bp6bp (MTHFR 677/TS 1494) combinations, respectively. The results suggested that the combined MTHFR 677/MTHFR 1298 genotype might be associated with increased risk of RIF. To the best of our knowledge, this study is the first to elucidate the potential association of MTHFR, TS and TSER polymorphisms with RIF risk in Korean patients.

[Association between the C46T polymorphism of coagulation factor â « gene and the involvement of factor â « activity in patients with unexplained recurrent spontaneous abortion].

OBJECTIVE: To explore the association between the C46T polymorphism of coagulation factor Ⅻ (FⅫ) gene and the involvement of FⅫ activity (FⅫ:C) in patients with unexplained recurrent spontaneous abortion (URSA), and to elucidate its role in the pathogenesis of URSA. METHODS: This study included 203 patients with URSA (URSA group) and 171 healthy women with at least one child and no history of infertility or miscarriage (control group) in the southern area of Zhejiang Province. The C46T polymorphism of the FⅫ gene was analyzed with matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDI-TOF-MS) in all subjects. The values of prothrombin time, activated partial thromboplastin time (APTT), fibrinogen, FⅫ:C and other coagulant parameters were determined. The frequency distribution of the wild-type (CC), heterozygote (CT), homozygote (TT) genotypes and C and T alleles were compared between the patients and controls. A comprehensive analysis of association was conducted between C46T genotypes and the FⅫ:C levels in URSA patients. RESULTS: The CC, CT, TT genotypes of the FⅫ gene were observed in 7 (3.4%, 7/203), 83 (40.9%, 83/203) and 113 (55.7%, 113/203) patients with URSA versus 7 (4.1%, 7/171), 46 (26.9%, 46/171) and 118 (69.0%, 118/171) controls. The frequency of CT in the patients with URSA was significantly higher than that in controls, but the frequency of TT in the patients was lower than that in controls (χ(2)=7.939, OR=1.884, 95%CI: 1.210-2.935, P<0.05). The frequencies of allele C and allele T were observed in 97 (23.9%, 97/406) and 309 (76.1%, 309/406) patients with URSA versus 60 (17.5%, 60/342) and 282 (82.5%, 282/342) controls. The distribution frequency of allele T in URSA group was lower than that in control group (χ(2)=4.510, OR=1.475, 95%CI: 1.029-2.115, P<0.05). The FⅫ: C levels in the patients were (102±13)% in CC genotype, (78±11)% in CT genotype and (59±9)% in TT genotype, respectively. The differences of the FⅫ: C levels between the CC and CT, CT and TT, CC and TT genotypes in the patients were significant (all P<0.05). CONCLUSIONS: The low level of FⅫ:C maybe result from the T allele of the FⅫ gene in URSA patients. The CT genotype might be relative to the pathogenesis of URSA in a Chinese Han female population from the southern area of Zhejiang province.

Meta-analyses of associations between interleukin-10 polymorphisms and susceptibility to recurrent pregnancy loss.

OBJECTIVE: The aim of this study was to investigate whether interleukin-10 (IL-10) polymorphisms are associated with susceptibility to recurrent pregnancy loss (RPL). METHODS: We conducted a literature search using the PubMed and EMBASE databases and performed meta-analyses on the associations between IL-10 -1082 G/A, -819 C/T, and -592 C/A polymorphisms and RPL, using fixed- or random-effects models. RESULTS: A total of 15 papers involving 1858 RPL patients and 1949 controls were considered in this study. Meta-analysis of IL-10 -1082 G/A polymorphism revealed no association between RPL and the IL-10 -1082 G allele (OR=0.999, 95% CI=0.815-1.223, p=0.989). However, meta-analysis of IL-10 -819 C/T polymorphism in all study subjects revealed an association between RPL and the IL-10 -819 C allele (OR=0.680, 95% CI=0.498-0.927, p=0.015). Stratification by ethnicity indicated an association between the IL-10 -819 C allele and RPL in the Asian group (OR=0.421, 95% CI=0.226-0.783, p=0.006), but not in the Caucasian and Arab groups (OR=1.053, 95% CI=0.218-5.077, p=0.949, and OR=0.800, 95% CI=0.606-1.081, p=0.152, respectively). Furthermore, a relationship between the IL-10 -592 C allele and RPL was identified in the Asian group (OR=0.763, 95% CI=0.633-0.919, p=0.004), but not in the Caucasian and Arab groups. CONCLUSIONS: The meta-analyses demonstrate that IL-10 -819 C/T and -592 C/A polymorphisms are associated with RPL susceptibility in Asian women, but not in the Caucasian and Arab populations.

Methylenetetrahydrofolate reductase gene polymorphisms and recurrent pregnancy loss in China: a systematic review and meta-analysis.

PURPOSE: Recurrent pregnancy loss (RPL) is defined as two or more consecutive pregnancy losses before the 20th week of gestation with the same partner. Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms were reported to have an effect on embryonic development and pregnancy success. To clarify the effects of MTHFR polymorphisms on the risk of RPL in the Chinese population, a meta-analysis was performed. MATERIALS AND METHODS: Related studies were identified from Medline, Embase, Web of Science, and Chinese Databases up to March 7th, 2015. We extracted the number of both C677T and A1298C genotypes in the cases and controls. Odds ratios (ORs) and 95 % confidence intervals (95 % CIs) were used to estimate the associations. Data analysis was performed using Stata 13.1. RESULTS: Sixteen articles involving 1420 RPL cases and 1408 controls were included in this meta-analysis. MTHFR C677T polymorphism was significantly associated with RPL risk under dominant (TT + CT vs. CC; OR 2.10, 95 % CI 1.76-2.50), recessive (TT vs. CC + CT; OR 2.36, 95 % CI 1.92-2.90), heterozygote (CT vs. CC; OR 1.77, 95 % CI 1.32-2.37), homozygote (TT vs. CC; OR 3.55, 95 % CI 2.76-4.56), and additive (T vs. C; OR 1.83, 95 % CI 1.64-2.05) model. Sensitivity analyses excluding studies that deviated from HWE did not change the direction of effect. For the A1298C mutation, no significant association was found. The Egger's regression asymmetry test showed no significant publication bias. CONCLUSIONS: Identification of MTHFR C677T mutation would have some implication for primary prevention of RPL and screening of high-risk individuals in China. Large well-designed researches are needed to fully describe the associations.

Ethnic differences in the association of thrombophilic polymorphisms with obstetric complications in Slovak and Roma (Gypsy) populations.

AIMS: Hereditary as well as acquired thrombophilia is associated with a higher incidence of severe obstetric complications such as preeclampsia, spontaneous pregnancy loss, placental abruption, and fetal growth retardation. The aim of our study was to examine the association of selected thrombophilic polymorphisms (factor V Leiden, MTHFR C677T, and MTHFR A1298C) with pregnancy complications in the Slovak majority population and the Roma (Gypsy) ethnic population. The study included 354 women; 120 patients and 105 controls from the Slovak majority population, 50 patients and 79 controls from the Slovak Roma population. Genotyping was performed by the real-time polymerase chain reaction method using TaqMan(®) MGB probes. RESULTS: A statistically significant higher frequency of factor V Leiden (p=0.001, odds ratio [OR]=5.9) and MTHFR C677T polymorphism (p=0.011, OR=1.7) was observed in the Slovak majority patient group compared to the control group. The incidence of MTHFR A1298C polymorphism between patients and controls did not differ significantly. None of the three polymorphisms studied was in association with pregnancy complications in the group of Roma women. CONCLUSIONS: Our study has confirmed the variable distribution of selected thrombophilic polymorphisms in different ethnic groups as well as their various effects on the clinical phenotype.

Frequency of euploid miscarriage is increased in obese women with recurrent early pregnancy loss.

OBJECTIVE: To determine whether the frequency of euploid miscarriage is increased in obese women with recurrent early pregnancy loss (REPL). DESIGN: Observational cohort study using prospectively collected data. SETTING: Academic RPL program. PATIENT(S): A total of 372 women with REPL, defined as ≥2 pregnancy losses<10 weeks, and at least one ultrasound-documented miscarriage with chromosome results. INTERVENTION(S): Body mass index (BMI) was measured at the initial consultation and at each subsequent pregnancy. Conventional cytogenetic analysis and, when indicated, microsatellite analysis and/or comparative genomic hybridization was performed. MAIN OUTCOME MEASURE(S): Frequency of euploid miscarriage in obese (BMI≥30 kg/m2) and nonobese (BMI<30 kg/m2) subjects, before and subsequent to REPL evaluation. RESULT(S): There were 578 miscarriages with chromosome results. Of the subjects, 18% were obese at the time of miscarriage. The mean maternal age at miscarriage was similar between the obese and nonobese groups. Due to the high rate of maternal cell contamination in the prior miscarriages, only subsequent miscarriages with chromosome results were included in the primary analysis. Of the 117 subsequent miscarriages, the frequency of an euploid miscarriage among obese women was 58% compared with 37% of nonobese women (relative risk=1.63; 95% confidence interval 1.08-2.47). CONCLUSION(S): Obese women with REPL have an increased frequency of euploid miscarriage, which is a known risk factor for subsequent miscarriage.

The ESR1 gene in unexplained recurrent spontaneous abortion.

Recurrent spontaneous abortion (RSA) is a health problem that affects nearly 1% of fertile couples. However, the underlying etiology and mechanism(s) remain elusive. The aim of this study was to investigate estrogen receptor (ESR) 1 gene polymorphisms for risk association of unexplained recurrent spontaneous abortion (URSA) in the Chinese Han population. The entire coding region of the ESR1 gene was sequenced from 129 URSA patients and 183 healthy controls. There was a significant difference between the G allele and GG genotype distributions, of the ESR1 gene (XbaI) polymorphism, between the URSA and the control groups (χ(2) = 14.93, df = 1, p < 0.001, OR = 2.01 95% CI: 1.41-2.88 by allele; χ(2) = 12.24, df = 2, p = 0.002 by genotype). The PvuII polymorphism, C allele frequency was higher in RSA than in controls (41.9% vs. 34.7%, respectively). Women carrying C-G haplotype were associated with an increased risk of URSA in this population (permutation test p value = 0.016, OR = 1.76 95% CI: 1.19-2.59). Estrogen receptor 1 gene PvuII and XbaI polymorphisms were associated with URSA in a Chinese Han population. However, independent replication of these associations are necessary to assure veracity.

Mannose binding lectin genotypes are not associated with increased risk of unexplained recurrent pregnancy loss.

PURPOSE: Immune response to infections has been associated with recurrent pregnancy loss (RPL). Low plasma mannose binding lectin (MBL) levels, an innate immunity factor in infections, has been related to RPL. In this study, we tested the hypothesis that MBL genotypes that are known to cause reduced plasma MBL levels are significantly more frequent among women experiencing unexplained RPL. METHODS: This study included 219 Caucasian women diagnosed with unexplained RPL and 236 control women. All participants were genotyped for two promoter (-550 C > G and -221 G > C) and three missense (R52C, G54D and G57E) mutations in exon 1. These mutations are known to be associated with variations in plasma MBL levels. Genotype frequencies were estimated by gene counting and were compared to the expectation of Hardy-Weinberg equilibrium by chi-squared (X(2)) analysis and Fisher's exact test. Allele and genotype frequencies were compared in cases and controls using X(2) contingency table analysis. RESULTS: There was no difference in demographics between cases and controls. The number of miscarriages in the participants with RPL ranged from 2 to 10 spontaneous abortions (SAB's) per participant. Populations genotyped were in Hardy-Weinberg equilibrium. There was no association between a history of RPL and multi-SNP genotypes at the MBL locus. In unexplained RPL, the number of SAB's and live birth rates were unaffected by MBL genotype. There was no association between MBL genotype and the risk of unexplained RPL. The occurrence of live birth was not associated with MBL genotype. CONCLUSION: Genotypes known to cause low MBL plasma levels are not associated with an increased risk of unexplained RPL.

A modest but significant effect of CGB5 gene promoter polymorphisms in modulating the risk of recurrent miscarriage.

OBJECTIVE: To confirm the effect of single nucleotide polymorphisms (SNPs) in chorionic gonadotropin beta (CGB) genes in modulating the susceptibility to recurrent miscarriage (RM) in Danes and in a meta-analysis across Danes and the discovery samples from Estonia and Finland. DESIGN: Case-control association study, restriction fragment length polymorphism genotyping, resequencing. SETTING: Fertility clinics at the Rigshospitalet, Copenhagen, and Aalborg Hospital, Aalborg, Denmark. PATIENT(S): Four hundred fifty Danish women and men from couples with RM and 119 women with children and no miscarriages in new study. A total of 634 women and men from RM couples and 314 female controls in a combined study of Estonians, Finns, and Danes. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Distribution of CGB5 and CGB8 allele and haplotype frequencies in patients and controls. RESULT(S): For the majority of studied SNPs, the allelic and haplotypic distribution differed statistically between the Danish and the previous Estonian-Finnish sample. In Danes, two CGB5 promoter SNPs (c5-155; c5-142) exhibited a nonsignificant trend for higher allele frequency in fertile women compared with RM patients. The meta-analysis of results from three populations confirmed a modest but significant effect on carriage of c5-155C (odds ratio = 0.64; 95% confidence interval [CI] 0.44-0.94) and c5-142A (odds ratio = 0.66; 95% CI, 0.45-0.94) variants in reducing the risk of RM. None of the investigated genetic variants in the CGB8 gene was associated with RM. CONCLUSION(S): Carriage of particular variants in the promoter of the CGB5 gene seems to protect against RM. No common genetic variants in CGB5 and CGB8 were associated with increased RM susceptibility in the studied North European populations.