MTHFR polymorphisms C677T and A1298C and associations with IVF outcomes in Brazilian women

Associations between maternal MTHFR polymorphisms and embryological outcomes in Korean patients with infertility undergoing IVF/ICSI cycles

OBJECTIVE

Methylenetetrahydrofolatereductase (MTHFR) is important for folate metabolism, which is involved in DNA synthesis and cell growth. However, the relationship between Maternal MTHFR polymorphisms and outcomes in assisted reproduction remains controversial. This is the first study to explore the effect of MTHFR polymorphisms on the embryological outcomes in in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles in Korean patients with infertility.

MATERIALS AND METHODS

This retrospective cohort study included 173 women who underwent MTHFR genotyping between July, 2021 and June, 2022. The embryologic outcomes of 301 IVF/ICSI cycles were compared between groups according to MTHFR polymorphisms using ANOVA and Chi-square test.

RESULTS

Oocyte maturation rates were 80.0%, 75.0%, and 71.4% for MTHFR 677CC, 677CT, and 677TT, respectively. Cleaved embryo formation and transplantable embryo rates were comparable across various maternal MTHFR 677 genotypes. Good-quality embryo (GQE) rate was higher for MTHFR 677CT than those for 677CC and 677TT (40.0% vs. 29.4%, p = 0.001 and 40.0% vs. 33.3%, p = 0.025, respectively). When analyzing the combined MTHFR genotypes, the oocyte maturation rate was significantly lower in 677TT than in 677CC 1298AA/677CC 1298AC and 677CC 1298CC/677CT 1298AA/677CT 1298AC (71.4% vs. 76.7%, p = 0.012 and 71.4% vs. 75.7%, p = 0.029, respectively). The MTHFR 677CC/1298CC, 677CT/1298AA, and 677CT/1298AC genotypes had the highest GQE rates.

CONCLUSIONS

MTHFR 677TT genotype, which had the lowest enzymatic activity, had the lowest oocyte maturation rate. The combined MTHFR 677CC/1298CC, 677CT/1298AA, and 677CT/1298AC genotypes with intermediate enzyme activities had higher GQE rates. However, no differences were observed in the transplantable embryo rate between MTHFR genotypes.

Exploring the correlation between homocysteine, red blood cell folate and MTHFRC677T genotypes with female infertility

Aim: To investigate the association between serum homocysteine (HCY) levels, red blood cell folate (RCF) levels, methylenetetrahydrofolate reductase (MTHFR) gene polymorphism and infertility.Materials & methods: Serum HCY and RCF levels and C677T polymorphism of MTHFR gene were analyzed in 149 infertile patients and 223 women of normal reproductive age with healthy childbirth history.Results: The HCY level of MTHFR C677T TT genotype infertility patients was higher than that of women of normal reproductive age, while the RCF level was not significantly different between the two groups.Conclusion: Serum HCY levels increased in infertility patients, and the MTHFR C677T TT genotype in childbearing-aged women are associated with a higher risk of infertility. The results showed that HCY level and MTHFR C677T genotype were closely related to infertility.

The Role of One-Carbon Metabolism and Methyl Donors in Medically Assisted Reproduction: A Narrative Review of the Literature

One-carbon (1-C) metabolic deficiency impairs homeostasis, driving disease development, including infertility. It is of importance to summarize the current evidence regarding the clinical utility of 1-C metabolism-related biomolecules and methyl donors, namely, folate, betaine, choline, vitamin B12, homocysteine (Hcy), and zinc, as potential biomarkers, dietary supplements, and culture media supplements in the context of medically assisted reproduction (MAR). A narrative review of the literature was conducted in the PubMed/Medline database. Diet, ageing, and the endocrine milieu of individuals affect both 1-C metabolism and fertility status. In vitro fertilization (IVF) techniques, and culture conditions in particular, have a direct impact on 1-C metabolic activity in gametes and embryos. Critical analysis indicated that zinc supplementation in cryopreservation media may be a promising approach to reducing oxidative damage, while female serum homocysteine levels may be employed as a possible biomarker for predicting IVF outcomes. Nonetheless, the level of evidence is low, and future studies are needed to verify these data. One-carbon metabolism-related processes, including redox defense and epigenetic regulation, may be compromised in IVF-derived embryos. The study of 1-C metabolism may lead the way towards improving MAR efficiency and safety and ensuring the lifelong health of MAR infants.

Homocysteine serum levels correlate with the number of failed IVF cycles even when within normal range

INTRODUCTION

Repeated implantation failure is a common challenge in daily practice. Homocysteine and vitamin B12 have been associated with reproductive processes among patients undergoing in vitro fertilization; however, their involvement in repeated implantation failure has not been assessed. We explored possible associations of serum homocysteine and vitamin B12 with repeated implantation failure.

MATERIAL AND METHODS

A retrospective analysis of 127 women who underwent ≥ 3 unsuccessful embryo transfers during 2005-2016, at the Fertility and In Vitro Fertilization Unit at Carmel Medical Center. After at least 3 IVF failures serum levels of homocysteine and vitamin B12 were measured.

RESULTS

The mean patient age was 33.5 ± 5.2 years. The mean number of embryo transfers was 4.6 ± 1.5. The mean total cumulative number of embryos transferred was 10.4 ± 5.2. Mean serum levels of homocysteine were 8.6 ± 3.7 µM/L, and of vitamin B12 were 302.5 ± 155.3 pg/ml. Homocysteine levels were within the normal range (< 14 µM/L) in 95.8% of the patients. Yet, the levels of homocysteine correlated with both the number of failed embryo transfers (r = 0.34, p = 0.004) and the total cumulative number of transferred embryos (r = 0.36, p = 0.002).

CONCLUSIONS

Our findings suggest an association between serum homocysteine levels and the occurrence of repeated implantation failure, even when homocystein levels were within the normal range. It should be studied whether nutritional supplementation to modulate serum homocysteine levels may improve treatment outcome.

The role of thrombophilias in reproduction: A swot analysis

Thrombophilia is a group of inherited or acquired coagulation disorders that have been associated with reproductive failure. However, there are still no clear recommendations on whether its inclusion in the initial study of the infertile couple or patients with recurrent implantation failure is necessary. In this discussion paper, based on a SWOT (strengths, weaknesses, opportunities, threats) analysis, the different aspects of the repercussions of thrombophilia screening and treatment in reproduction are evaluated. To avoid possible subjectivity in the analysis and results of this study, researchers followed Oxford criteria for the evaluation of evidence. The results from the evaluation of the reviewed bibliography seem to indicate that, pending new evidence, it would be advisable not to include thrombophilia screening in the initial baseline study of the infertile couple. There is no evidence to support a clear association between thrombophilia and implantation failure or infertility. Thrombophilia testing in this setting may increase cost, with minimal potential benefit and lead to inappropriate use of anticoagulants with possible deleterious adverse effects. Future well-designed studies are needed to assess the possible benefit of anticoagulant therapy in infertile thrombophilic patients with implantation failure.

Association between maternal MTHFR C677T/A1298C combination polymorphisms and IVF/ICSI outcomes: a retrospective cohort study

STUDY QUESTION

What are the roles of maternal 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C combination polymorphisms on the embryological and clinical outcomes of IVF/ICSI?

SUMMARY ANSWER

Our study reveals for the first time that the oocyte maturation potential gradually decreases with a reduction of maternal MTHFR activity determined by combined C677T/A1298C polymorphisms, while embryo quality was worse in women with intermediate MTHFR activity.

WHAT IS KNOWN ALREADY

Although many previous studies have explored the association between MTHFR polymorphisms and IVF/ICSI outcomes, the results remain contradictory due to inadequate samples, no adjustment for potential confounders and/or the study of C677T and A1298C separately. Few studies have systematically investigated the exact role of MTHFR activity determined by combined C677T/A1298C polymorphisms on the embryological and clinical outcomes of IVF/ICSI.

STUDY DESIGN SIZE DURATION

This is a retrospective cohort study investigating 1160 women who were referred for MTHFR genotyping and IVF/ICSI treatment at Peking University Third Hospital from May 2017 to May 2020.

PARTICIPANTS/MATERIALS SETTING METHODS

Women who were referred for MTHFR genotyping and their first IVF/ICSI treatment at our hospital were included and those undergoing preimplantation genetic testing cycles were excluded. The included women were divided into different cohorts according to their C677T, A1298C and combined C677T/A1298C genotypes. The embryological outcomes, including oocytes retrieved, metaphase II oocytes, oocyte maturation rate, normal fertilization rate and transplantable embryo rate, were evaluated by generalized linear regression models. The clinical outcomes, including biochemical pregnancy rate, clinical pregnancy rate and live birth rate, were evaluated by log-binomial regression models. All outcomes were adjusted for potential confounders.

MAIN RESULTS AND THE ROLE OF CHANCE

Women with the combined 677TT/1298AA genotype (hereafter abbreviated as TT/AA, as with other combined genotypes), whose enzyme activity was the lowest, had a lower oocyte maturation rate compared with those with the wild-type genotype (P = 0.007). Moreover, the oocyte maturation rate decreased linearly with the decline in MTHFR enzyme activity determined by combined C677T/A1298C genotypes (P-trend = 0.001). The combined CC/AC, CC/CC&CT/AA and CT/AC genotypes with intermediate enzyme activity were associated with a lower transplantable embryo rate (P = 0.013, 0.030 and 0.039, respectively). The differences in clinical outcomes between women with wild-type genotype and combined C677T/A1298C variant genotypes were not significant.

LIMITATIONS REASONS FOR CAUTION

Our study population had comparable embryological outcomes but worse clinical outcomes than other women undergoing IVF/ICSI treatment at our hospital. Therefore, the results related to the clinical outcomes should be generalized with caution. In addition, we did not detect the folate concentration of each patient during pregnancy. However, this might not have much influence on our results because almost all of our study participants took sufficient folic acid around pregnancy.

WIDER IMPLICATIONS OF THE FINDINGS

We provide a holistic view of the effect of MTHFR C677T and A1298C polymorphisms on the IVF/ICSI outcomes, which can contribute to providing reasonable folic acid supplementation suggestions for women with different MTHFR genotypes, especially for those with a low oocyte maturation rate and/or low embryo quality.

STUDY FUNDING/COMPETING INTERESTS

This work was funded by the National Natural Science Foundation of China (31871447, and 82101677), the National Key Research and Development Program (2019YFA0801400) and the Natural Science Foundation of Beijing Municipality (7202226). The authors declare that they have no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

MTHFR SNPs (Methyl Tetrahydrofolate Reductase, Single Nucleotide Polymorphisms) C677T and A1298C Prevalence and Serum Homocysteine Levels in >2100 Hypofertile Caucasian Male Patients

Methylation is a crucially important ubiquitous biochemical process, which covalently adds methyl groups to a variety of molecular targets. It is the key regulatory process that determines the acquisition of imprinting and epigenetic marks during gametogenesis. Methylation processes are dependent upon two metabolic cycles, the folates and the one-carbon cycles. The activity of these two cycles is compromised by single nucleotide polymorphisms (SNPs) in the gene encoding the Methylenetetrahydrofolate reductase (MTHFR) enzyme. These SNPs affect spermatogenesis and oocyte maturation, creating cytologic/chromosomal anomalies. The two main MTHFR SNP variants C677T (c.6777C>T) and A1298C (c.1298A>C) together with serum homocysteine levels were tested in men with >3 years’ duration of infertility who had failed several ART attempts with the same partner. These patients are often classified as having “idiopathic infertility”. We observed that the genetic status with highest prevalence in this group is the heterozygous C677T, followed by the combined heterozygous C677T/A1298C, and then A1298C; these three variants represent 65% of our population. Only 13.1% of the patients tested are wild type (WT), C677C/A1298A). The homozygous 677TT and the combined heterozygote 677CT/1298AC groups have the highest percentage of patients with an elevated circulating homocysteine level of >15 µMolar (57.8% and 18.8%, respectively, which is highly significant for both). Elevated homocysteine is known to be detrimental to spermatogenesis, and the population with this parameter is not marginal. In conclusion, determination of these two SNPs and serum homocysteine should not be overlooked for patients with severe infertility of long duration, including those with repeated miscarriages. Patients must also be informed about pleiotropic medical implications relevant to their own health, as well as to the health of future children.

Folate metabolism abnormalities in infertile patients with endometriosis

Background: Homocysteine levels can be impacted by enzymes variations. Aim: To correlate MTHFR, MTR and MTRR variants with homocysteine levels in the blood and follicular fluid and assisted reproduction results. Material & methods: MTHFR (rs2274976, rs1801131, rs1801133), MTR (rs1805087) and MTRR (rs1801394) genotyping was performed by TaqMan assays and compared with homocysteine levels, measured by ELISA, to oocytes retrieved and to the pregnancy status of women with endometriosis and controls. Results: The MTR G allele and GG genotype were more common in patients with endometriosis. They also showed lower levels of homocysteine and more clinical gestations. Epistasis analysis showed a model associated with gestational results, composed of MTHFR+MTR variants (CC+AG). Conclusion: The summation effect of variants in genes participating in folate metabolism was associated with pregnancy status in Brazilian women. MTR variants were more observed in endometriosis patients, as well as lower follicular Hcy levels and increased clinical pregnancy results.

MTHFR 677TT is associated with decreased number of embryos and cumulative live birth rate in patients undergoing GnRHa short protocol: a retrospective study

Background

Whether MTHFR C677T genotype affects pregnancy outcomes following assisted reproductive technology is conflicting. And the role of MTHFR C677T genotype on cumulative live birth has not been reported. This study aims to investigate the effect of MTHFR C677T genotype on cumulative live birth following in-vitro fertilization and embryo transfer (IVF-ET).

Methods

This is a retrospective cohort study that includes 1173 women undergoing their first IVF-ET. We retrospectively compared the reproductive outcomes among the groups stratified by MTHFR C677T genotypes (677CC, 677CT, 677TT). We performed interaction analysis to detect the factor that interacts with the MTHFR C677T genotype. Poisson regression analyses were used to evaluate the associations between MTHFR C677T genotypes with the number of transferable embryos and the number of good-quality embryos. Cox regression analysis was used to evaluate the association between MTHFR C677T genotypes with cumulative live birth. All regression analyses were adjusted with the confounding factors which may independently impact reproductive outcomes.

Results

There is a significant interactive effect of MTHFR 677TT genotype with GnRHa protocol on reproductive outcomes (P for interaction<0.05). MTHFR 677TT homozygous mutation was found to impact reproductive outcomes under GnRHa short protocol but not GnRHa long protocol. MTHFR 677TT is significantly associated with decreased number of transferable embryos (p-value=0.028), decreased number of good-quality embryos (p-value=0.005), and decreased cumulative live birth rate (p-value=0.024) in patients undergoing GnRHa short protocol. However, the clinical pregnancy rate, miscarriage rate and live birth rate at the first embryo transfer cycle were not significantly different between the groups under both protocols (p-values>0.05).

Conclusions

MTHFR 677TT genotype is associated with decreased number of transferable embryos, decreased number of good-quality embryos, and decreased cumulative live birth rate in the first complete cycle in patients undergoing GnRHa short protocol.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04506-4.

Association of paternal MTHFR polymorphisms (C677T) with clinical outcomes in ICSI treatment

PURPOSE

This study aims to investigate the association between paternal methylenetetrahydrofolate reductase (MTHFR) polymorphisms (C677T) and embryonic development, pregnancy, and neonatal outcomes in intracytoplasmic sperm injection (ICSI) treatment.

METHODS

A total of 191 infertile men undergoing ICSI treatment at the Reproductive and Genetic Hospital, The First Affiliated Hospital of USTC, were recruited between January 2020 and June 2021. The MTHFR C677T polymorphism genotyping was evaluated in these male patients, and they were stratified into three groups according to genotyping results: Control (CC), heterozygote mutated (CT), and mutated homozygote (TT). In addition, we conducted a comparative analysis of embryonic development, pregnancy, and neonatal outcomes among these three groups.

RESULTS

The embryonic development (including normal fertilization rate (80.14% vs. 83.06% vs. 85.10%; p = 0.37), high-quality embryo rate (45.26% vs. 43.69% vs. 46.04%; p = 0.72), blastocyst formation rate (42.47% vs. 43.18% vs. 39.38%; p = 0.62), implantation rate (42.47% vs. 36.25% vs. 41.22%; p = 0.62), and clinical pregnancy rate (64.71% vs. 58.75% vs. 66.67%; p = 0.59) were not comparable among these three groups. Moreover, no significant difference was observed in terms of pregnancy outcomes (including miscarriage rate (24.24% vs. 12.77% vs. 22.5%; p = 0.35) and live birth rate (49.02% vs. 51.25% vs. 51.66%; p = 0.96)). Additionally, no marked difference was observed in terms of neonatal outcome (including, preterm delivery rate (24% vs. 14.63% vs. 9.67%; p = 0.35), birth height (p = 0.75), birth weight (p = 0.35), neonatal sex (p = 0.48), gestational age at delivery (p = 0.24), Apgar score (p = 0.34), and birth defects (0% vs. 2% vs. 9%; p = 0.23) among the study groups.

CONCLUSION

The paternal MTHFR C677T polymorphism is not associated with embryo quality, pregnancy, or neonatal outcomes in ICSI treatment. Therefore, in our population, MTHFR polymorphisms do not provide helpful information in explaining ICSI failure.

The effect of A1298c polymorphism of the MTHFR gene on anti-Müllerian hormone levels: experimental and Web-based analysis

Background

The 5,10‐methylenetetrahydrofolate reductase (MTHFR) is an important enzyme of folate and methionine metabolism, which is expressed in human oocytes and preimplantation. Due to the involvement of MTHFR in female reproduction, we tend to evaluate the influence of MTHFR A1298C polymorphism on ovarian marker reserves such as serum anti‐Müllerian hormone (AMH) levels in women after in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI).

Methods

A total of 100 women, who underwent ART treatment due to male factor infertility, were recruited into this study. MTHFR A1298C polymorphism was detected by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) technique, and serum AMH concentrations were measured by an ultrasensitive enzyme‐linked immunosorbent assay (ELISA).

Results

Women with the CC genotype had higher AMH levels (4.15 ± 1.67 ng/ml), albeit not significant, than carriers with other genotypes after ovarian stimulation. No significant differences existed in terms of miscarriage and live birth rates among different genotype groups.

Conclusion

The presence of the C mutant allele of the 1298 polymorphism in the MTHFR gene led to an increasing trend in serum AMH concentrations; however, the numbers of oocytes retrieved decreased in women with mutated genotypes. The influence of the MTHFR C677T polymorphism on embryo quality and pregnancy rate after ART cycles remains unclear.

Involvement of single nucleotide polymorphisms in ovarian poor response

PURPOSE

Unpredictability in acquiring an adequate number of high-quality oocytes following ovarian stimulation is one of the major complications in controlled ovarian hyperstimulation (COH). Genetic predispositions of variations could alter the immunological profiles and consequently be implicated in the variability of ovarian response to the stimulation.

DESIGN

Uncovering the influence of variations in AMHR2, LHCGR, MTHFR, PGR, and SERPINE1 genes with ovarian response to gonadotrophin stimulation in COH of infertile women.

METHODS

Blood samples of the women with a good ovarian response (GOR) or with a poor ovarian response (POR) were collected. Genomic DNA was extracted, and gene variations were genotyped by TaqMan SNP Genotyping Assays using primer-probe sets or real-time PCR Kit.

RESULTS

Except for PGR (rs10895068), allele distributions demonstrate that the majority of POR patients carried minor alleles of AMHR2 (rs2002555, G-allele), LHCGR (rs2293275, G-allele), MTHFR (rs1801131, C-allele, and rs1801133, T-allele), and SERPINE1 (rs1799889, 4G allele) genes compared to the GOR. Similarly, genotypes with a minor allele in AMHR2, LHCGR, MTHFR, and SERPINE1 genes had a higher prevalence among POR patients with the polymorphic genotypes. However, further genotype stratification indicated that the minor alleles of these genes are not associated with poor response. Multivariate logistic analysis of clinical-demographic factors and polymorphic genotypes demonstrated a correlation between FSH levels and polymorphic genotypes of SERPINE1 in poor response status.

CONCLUSIONS

Despite a higher prevalence of AMHR2, LHCGR, MTHFR, and SERPINE1 variations in the patients with poor ovarian response, it seems that these variations are not associated with the ovarian response.

Effect of polymorphisms of MTHFR in controlled ovarian stimulation: a systematic review and meta-analysis

OBJECTIVE

Although several studies have reported a potential impact of methylenetetrahydrofolate reductase (MTHFR) polymorphisms on controlled ovarian stimulation (COS), the results remain controversial. The aim of the systematic review and meta-analysis was to evaluate the effect of MTHFR polymorphism on COS outcomes.

METHODS

PubMed, Web of Science, Embase, and Cochrane Central Register of Controlled Trials databases were searched up to December 2, 2020. COS clinical outcomes based on gene polymorphisms were included. Two reviewers independently extracted the data. The primary outcome was the number of oocytes retrieved. The secondary outcomes were the number of metaphase II (MII) oocytes, stimulation duration, basal follicle-stimulating hormone (FSH) level, FSH dosage, positive pregnancy test, ongoing pregnancy rate, clinical pregnancy rate, miscarriage rate, and live birth rate. Meta-analysis was performed using a fixed-effect model or random-effect model with Review Man 5.3.5. Mean difference (MD) with 95% confidence intervals (95%CIs) was calculated for continuous outcomes. The quality assessment of included studies was evaluated by using the Newcastle-Ottawa Scale.

RESULTS

Eleven studies were included in the systematic review, and seven studies with 2015 participants were included in the meta-analysis. Basal FSH level was significantly lower in CC homozygotes than TT homozygotes (four studies, 867 participants, MD - 0.54, 95%CI - 0.85 to - 0.23, P = 0.0006; I² = 0%) of MTHFR (rs1801133). FSH dose was significantly fewer in CC homozygotes compared with CT heterogeneous (three studies, 949 participants, MD - 75.78, 95%CI - 135.23 to - 16.33, P = 0.01; I² = 32%) or CT/TT model (three studies, 1097 participants, MD - 80.18, 95%CI - 135.54 to - 24.81, P = 0.005; I² = 42%). Differences in the oocytes retrieved and stimulation duration were insignificant. Gene variants on MTHFR (rs1801133) and MTHFR (rs1801131) were reported in ongoing pregnancy rate, clinical pregnancy rate, and live birth rate.

CONCLUSION

Studies to date indicate that polymorphisms of MTHFR could influence basal FSH level and FSH dose. The results could be useful to promote clinical practice on COS protocols. Further studies are needed to evaluate the clinical relevance of the multigene combination on COS.

MTHFR (methylenetetrahydrofolate reductase: EC 1.5.1.20) SNPs (single-nucleotide polymorphisms) and homocysteine in patients referred for investigation of fertility

Purpose

MTHFR, one of the major enzymes in the folate cycle, is known to acquire single-nucleotide polymorphisms that significantly reduce its activity, resulting in an increase in circulating homocysteine. Methylation processes are of crucial importance in gametogenesis, involved in the regulation of imprinting and epigenetic tags on DNA and histones. We have retrospectively assessed the prevalence of MTHFR SNPs in a population consulting for infertility according to gender and studied the impact of the mutations on circulating homocysteine levels.

Methods

More than 2900 patients having suffered at least two miscarriages (2 to 9) or two failed IVF/ICSI (2 to 10) attempts were included for analysis of MTHFR SNPs C677T and A1298C. Serum homocysteine levels were measured simultaneously.

Results

We observed no difference in the prevalence of different genetic backgrounds between men and women; only 15% of the patients were found to be wild type. More than 40% of the patients are either homozygous for one SNP or compound heterozygous carriers. As expected, the C677T SNP shows the greatest adverse effect on homocysteine accumulation. The impact of MTHFR SNPs on circulating homocysteine is different in men than in women.

Conclusions

Determination of MTHFR SNPs in both men and women must be seriously advocated in the presence of long-standing infertility; male gametes, from MTHFR SNPs carriers, are not exempted from exerting a hazardous impact on fertility. Patients should be informed of the pleiotropic medical implications of these SNPs for their own health, as well as for the health of future children.

Association of homocysteine with IVF/ICSI outcomes stratified by MTHFR C677T polymorphisms: a prospective cohort study

RESEARCH QUESTION

What is the association between homocysteine (Hcy) and IVF/intracytoplasmic sperm injection (ICSI) outcomes, stratified by methylenetetrahydrofolate reductase (MTHFR) C677T polymorphisms?

DESIGN

This prospective cohort study recruited 1011 infertile women undergoing IVF/ICSI treatment for the first time at the International Peace Maternity and Child Health Hospital between June 2015 and March 2018.

RESULTS

The concentration of total serum Hcy was significantly negatively associated with clinical pregnancy and implantation rate. When adjusted for maternal and paternal age and educational level, maternal body mass index, and FSH and oestradiol concentrations, logistic regression analysis showed that women with higher Hcy had a higher risk of unsuccessful pregnancy. After stratification by MTHFR C677T polymorphisms and adjustment for confounding factors, a higher risk of unsuccessful pregnancy and a significantly lower implantation rate only existed in women with higher Hcy concentration in the MTHFR C677T TT genotype. There was no significant association between Hcy concentrations and other ovarian stimulation outcomes (oocytes retrieved, metaphase II stage oocytes, fertilization rate, cleavage rate, high-quality embryo rate) or neonatal outcomes (preterm birth, gestational age at delivery, Caesarean section, birthweight, small for gestational age, large for gestational age or birth defects).

CONCLUSIONS

Hcy is highly negatively associated with clinical pregnancy and implantation rate during the first IVF/ICSI cycle, especially in women carrying the MTHFR C677T TT genotype. Other factors with impacts on reproductive outcomes, such as stage of embryo transferred, other factors involved in folate metabolism, preimplantation genetic testing, etc., should be taken into account in further research.

Embryonic MTHFR contributes to blastocyst development

PURPOSE

Reduction in methylenetetrahydrofolate reductase (MTHFR) activity due to genetic variations in the MTHFR gene has been controversially implicated in subfertility in human in vitro fertilization. However, there is no direct gene-knockdown study of embryonic MTHFR to assess its involvement in mammalian preimplantation development. The purpose of this study is to investigate expression profiles and functional roles of MTHFR in bovine preimplantation development.

METHODS

Reverse transcription-quantitative PCR (RT-qPCR) and analysis of publicly available RNA-seq data were performed to reveal expression levels of MTHFR during bovine preimplantation development. We knocked down MTHFR by siRNA-mediated RNA interference from the 8- to 16-cell stage and assessed the effects on preimplantation development.

RESULTS

The RT-qPCR analysis showed relatively high MTHFR expression at the GV oocyte stage, which was decreased toward the 8- to 16-cell stage and then slightly restored at the blastocyst stage. Public data-based analysis also showed the similar pattern of expression with substantial embryonic expression at the blastocyst stage. MTHFR knockdown reduced the blastocyst rate (P < 0.01) and the numbers of total (P < 0.0001), trophectoderm (P < 0.0001), and inner cell mass (P < 0.001) cells.

CONCLUSION

The results indicate that embryonic MTHFR is indispensable for normal blastocyst development. The findings provide insight into the debatable roles of MTHFR in fertility and may be applicable for the improvement of care for early embryos via modulation of surrounding folate-related nutritional conditions in vitro and/or in utero, depending on the parental and embryonic MTHFR genotype.

MTHFR C677T polymorphism is associated with follicle-stimulating hormone levels and controlled ovarian hyperstimulation response: a retrospective study from the clinical database

OBJECTIVE

To evaluate the impact of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism with clinical data analysis in controlled ovarian hyperstimulation (COH) of infertile women in the Intravenous Infusion Safety Evaluation Center of Hunan Province, People's Republic of China.

DESIGN

Genetic Association Study.

SETTING

Reproductive medicine clinical.

PATIENT(S)

This genetic association study included 722 infertile women who received the standard long treatment protocol with accessible and complete electronic medical records.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The clinical parameters were obtained from the Intravenous Infusion Safety Evaluation center.

RESULT(S)

Basal FSH levels in the TT group were significantly higher than those of the CC group. The FSH levels after down-regulation in the TT group were higher than those of CC/CT genotypes. The TT genotype patients received significantly higher total doses of GnRH agonist and FSH compared with CC/CT genotypes, whereas the total dose of hCG was higher in the CT genotypes compared with the CC/TT genotypes. Further association analysis between hormone levels and COH outcomes indicated significantly negative correlation of basal FSH levels with antral follicle count and number of oocytes as well as the down-regulation FSH levels with the number of metaphase II oocytes and oocytes.

CONCLUSION(S)

The MTHFR C677T polymorphism was associated with high doses of ovarian stimulation medications, as well as higher FSH levels. The negative correlation between FSH levels and the number of oocytes suggested that C677T polymorphism may play a role in the poor prognosis of COH oocytes. This needs to be studied in future prospective studies with longer follow-up.

Pharmacogenomics in IVF: A New Era in the Concept of Personalized Medicine

Pharmacogenomics is a promising approach in the field of individualized medicine in in vitro fertilization (IVF) treatment that aims to develop optimized pharmacotherapy depending on the genetic background of each infertile woman, thus to ensure maximum effectiveness of the medication used, with minimal side effects. The unique genetic information of each infertile woman, in combination with already known, as well as new predictors of ovarian response and the progress of pharmacoepigenomics, is anticipated to greatly benefit the process of controlled ovarian stimulation. This review analyses current data on IVF pharmacogenomics, a new approach that is gradually moving to the frontline of modern IVF treatment.

Association between in vitro fertilization outcomes and inherited thrombophilias: a meta-analysis

PURPOSE

The aim of this study was to determine whether in vitro fertilization (IVF) outcomes are associated with inherited thrombophilias.

METHODS

Several databases including PubMed, Embase, and Cochrane Library were retrieved up to 12 January 2016. The quality of the included studies was assessed by two authors. The associations of the following mutations in inherited thrombophilias and IVF outcomes were explored: factor V Leiden (FVL), prothrombin gene G20210A mutation (PGM), 5,10-methylentetrahydrofolate reductase (MTHFR) C677T, MTHFR (A1298C) and activated protein C resistance (APCR). The main outcome measures included CPR and implantation rate (IR). The relative risk (RR) and its 95 % confidence interval (CI) were calculated for effect index. Heterogeneity test was evaluated by Chi-square based on Q statistic and I (2) statistics.

RESULTS

A total of seven articles published between 2007 and 2015 with the ages of subjects between 30.9 and 36.2 were included. For subgroups analysis of CPR or IR, there were no significant differences in MTHFR (C377T), MTHFR (A1298C), FVL, PGM, and FVL/PGM mutation were found between the mutation group and control group (P > 0. 05).

CONCLUSIONS

IVF outcomes are not associated with FVL, PGM, MTHFR (C677T), MTHFR (A1298C), and APCR mutation in inherited thrombophilias.

Multiple thrombophilic single nucleotide polymorphisms lack a significant effect on outcomes in fresh IVF cycles: an analysis of 1717 patients

PURPOSE

The aim of the study is to determine if thrombophilic single nucleotide polymorphisms (SNPs) affect outcomes in fresh in vitro fertilization (IVF) cycles in a large general infertility population.

METHODS

A prospective cohort analysis was performed at a university-affiliated private IVF center of female patients undergoing fresh non-donor IVF cycles. The effect of the following thrombophilic SNPs on IVF outcomes were explored: factor V (Leiden and H1299R), prothrombin (G20210A), factor XIII (V34L), β-fibrinogen (-455G → A), plasminogen activator inhibitor-1 (4G/5G), human platelet antigen-1 (a/b9L33P), and methylenetetrahydrofolate reductase (C677T and A1298C). The main outcome measures included positive pregnancy test, clinical pregnancy, embryo implantation, live birth, and pregnancy loss.

RESULTS

Patients (1717) were enrolled in the study, and a total of 4169 embryos were transferred. There were no statistically significant differences in positive pregnancy test, clinical pregnancy, embryo implantation, live birth, or pregnancy loss in the analysis of 1717 patients attempting their first cycle of IVF. Receiver operator characteristics and logistic regression analyses showed that outcomes cannot be predicted by the cumulative number of thrombophilic mutations present in the patient.

CONCLUSIONS

Individual and cumulative thrombophilic SNPs do not affect IVF outcomes. Therefore, initial screening for these SNPs is not indicated.