The homocysteine pathway in human subfertility

Subfertility, defined as at least one year of unprotected intercourse with the same partner without conception, affects ten to fifteen percent of couples in the western world. Depending on the duration of the subfertility, a female factor is the dominant cause of subfertility in around 50%, a male factor in 20-26% and the cause is unexplained in 25-30%. In most couples, subfertility is of multifactorial origin and should therefore be considered as a complex disease. Whereas genetic causes are difficult to modulate, environmental and lifestyle factors implicated in reproduction are potentially amendable to curative or preventive measures. Worldwide, an increasing number of couples are treated by assisted reproductive technology (ART) to achieve pregnancy. Currently, the chance of achieving a clinical pregnancy is around 28-31% per started in vitro fertilization (IVF) cycle with or without intracytoplasmic sperm injection (ICSI) in the Netherlands. The advantage of the introduction of IVF and ICSI treatment is that it gives access to and information about the direct environment of the gametes and early developing embryo. On the other hand, IVF and ICSI treatment is introducing an artifactual endocrinologic milieu which may affect the quality of the embryo. Whether concentrations of nutrients and enzymes change due to ovarian hyperstimulation is unclear, but it has already been demonstrated that different ovarian stimulation regimens increase the rates of embryo aneuploidy

Assessment of risk of ALS conferred by the GGGGCC hexanucleotide repeat expansion in C9orf72 among first-degree relatives of patients with ALS carrying the repeat expansion

Objectives: We aimed to estimate the age-related risk of ALS in first-degree relatives of patients with ALS carrying the C9orf72 repeat expansion. Methods: We included all patients with ALS carrying a C9orf72 repeat expansion in The Netherlands. Using structured questionnaires, we determined the number of first-degree relatives, their age at death due to ALS or another cause, or age at time of questionnaire. The cumulative incidence of ALS among first-degree relatives was estimated, while accounting for death from other causes. Variability in ALS risk between families was evaluated using a random effects hazards model. We used a second, distinct approach to estimate the risk of ALS and FTD in the general population, using previously published data. Results: In total, 214 of the 2,486 (9.2%) patients with ALS carried the C9orf72 repeat expansion. The mean risk of ALS at age 80 for first-degree relatives carrying the repeat expansion was 24.1%, but ranged between individual families from 16.0 to 60.6%. Using the second approach, we found the risk of ALS and FTD combined was 28.7% (95% CI 17.8%–54.3%) for carriers in the general population. Conclusions: On average, our estimated risk of ALS in the C9orf72 repeat expansion was lower compared to historical estimates. We showed, however, that the risk of ALS likely varies between families and one overall penetrance estimate may not be sufficient to describe ALS risk. This warrants a tailor-made, patient-specific approach in testing. Further studies are needed to assess the risk of FTD in the C9orf72 repeat expansion

Endometrial scratching in women with one failed IVF/ICSI cycle-outcomes of a randomised controlled trial (SCRaTCH)

STUDY QUESTION: Does endometrial scratching in women with one failed IVF/ICSI treatment affect the chance of a live birth of the subsequent fresh IVF/ICSI cycle? SUMMARY ANSWER: In this study, 4.6% more live births were observed in the scratch group, with a likely certainty range between -0.7% and +9.9%. WHAT IS KNOWN ALREADY: Since the first suggestion that endometrial scratching might improve embryo implantation during IVF/ICSI, many clinical trials have been conducted. However, due to limitations in sample size and study quality, it remains unclear whether endometrial scratching improves IVF/ICSI outcomes. STUDY DESIGN, SIZE, DURATION: The SCRaTCH trial was a non-blinded randomised controlled trial in women with one unsuccessful IVF/ICSI cycle and assessed whether a single endometrial scratch using an endometrial biopsy catheter would lead to a higher live birth rate after the subsequent IVF/ICSI treatment compared to no scratch. The study took place in 8 academic and 24 general hospitals. Participants were randomised between January 2016 and July 2018 by a web-based randomisation programme. Secondary outcomes included cumulative 12-month ongoing pregnancy leading to live birth rate. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women with one previous failed IVF/ICSI treatment and planning a second fresh IVF/ICSI treatment were eligible. In total, 933 participants out of 1065 eligibles were included (participation rate 88%). MAIN RESULTS AND THE ROLE OF CHANCE: After the fresh transfer, 4.6% more live births were observed in the scratch compared to control group (110/465 versus 88/461, respectively, risk ratio (RR) 1.24 [95% CI 0.96-1.59]). These data are consistent with a true difference of between -0.7% and +9.9% (95% CI), indicating that while the largest proportion of the 95% CI is positive, scratchin

The preconception nutritional status of women undergoing fertility treatment: Use of a one-year post-delivery assessment

Background&Aims - A poor maternal nutritional status in the preconception period is associated with adverse pregnancy outcomes. A valid standardized assessment period after pregnancy reflecting the preconception nutritional status is missing. Therefore, this study aimed to validate the assessment period at around 1 year after delivery in women undergoing fertility treatment. Methods - In a prospective study including 30 women with a fertility problem, we compared nutrient intakes from a food frequency questionnaire and biomarkers related to the homocysteine pathway in blood, at two assessment periods, i.e., preconceptionally and 1 year after delivery. We used a linear mixed model and adjusted for possible confounders, such as body mass index and folic acid supplement use. Results - The energy-adjusted nutrient intakes were not significantly different between the two assessment periods, except for higher retinol, alcohol and vitamin B2 and lower carbohydrate intakes at around 1 year after delivery. The intraclass correlation coefficients of the nutrients ranged from 0.3 to 0.7. After adjustment, none of the biomarkers was significantly different between the two assessment periods. The intraclass correlation coefficients of the biomarkers were all =0.5. Conclusions - An assessment at around 1 year after delivery seems to adequately reflect the preconception nutritional status of women with a fertility problem, however larger confirmatory studies are required

The preconception nutritional status of women undergoing fertility treatment: Use of a one-year post-delivery assessment

Background&Aims - A poor maternal nutritional status in the preconception period is associated with adverse pregnancy outcomes. A valid standardized assessment period after pregnancy reflecting the preconception nutritional status is missing. Therefore, this study aimed to validate the assessment period at around 1 year after delivery in women undergoing fertility treatment. Methods - In a prospective study including 30 women with a fertility problem, we compared nutrient intakes from a food frequency questionnaire and biomarkers related to the homocysteine pathway in blood, at two assessment periods, i.e., preconceptionally and 1 year after delivery. We used a linear mixed model and adjusted for possible confounders, such as body mass index and folic acid supplement use. Results - The energy-adjusted nutrient intakes were not significantly different between the two assessment periods, except for higher retinol, alcohol and vitamin B2 and lower carbohydrate intakes at around 1 year after delivery. The intraclass correlation coefficients of the nutrients ranged from 0.3 to 0.7. After adjustment, none of the biomarkers was significantly different between the two assessment periods. The intraclass correlation coefficients of the biomarkers were all =0.5. Conclusions - An assessment at around 1 year after delivery seems to adequately reflect the preconception nutritional status of women with a fertility problem, however larger confirmatory studies are required

Low folate in seminal plasma is associated with increased sperm DNA damage

Objective: To determine associations between vitamin B status, homocysteine (tHcy), semen parameters, and sperm DNA damage.Design: Observational study.Setting: A tertiary referral fertility clinic.Patients: Two hundred fifty-one men of couples undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment, with subgroups of fertile (n = 70) and subfertile men (n = 63) defined according to semen concentration and proven fertility.Intervention: None.Main Outcome Measure: The DNA fragmentation index (DFI) as marker of sperm DNA damage determined using the sperm chromatin structure assay (SCSA), and semen parameters assessed according to World Health Organization criteria; tHcy, folate, cobalamin, and pyridoxine concentrations determined in seminal plasma and blood.Result: In the total group of fertile and subfertile men, all biomarkers in blood were statistically significantly correlated with those in seminal plasma. No correlation was found between the biomarkers in blood and the semen parameters. In seminal plasma, both tHcy and cobalamin positively correlated with sperm count. Folate, cobalamin, and pyridoxine were inversely correlated with ejaculate volume. In fertile men, seminal plasma folate showed an inverse correlation with the DNA fragmentation index.Conclusion: Low concentrations of folate in seminal plasma may be detrimental for sperm DNA stability.<br/

Endometrial scratching in women with implantation failure after a first IVF/ICSI cycle; does it lead to a higher live birth rate? The SCRaTCH study: a randomized controlled trial (NTR 5342)

Contains fulltext : 177721.pdf (publisher's version ) (Open Access)BACKGROUND: Success rates of assisted reproductive techniques (ART) are approximately 30%, with the most important limiting factor being embryo implantation. Mechanical endometrial injury, also called 'scratching', has been proposed to positively affect the chance of implantation after embryo transfer, but the currently available evidence is not yet conclusive. The primary aim of this study is to determine the effect of endometrial scratching prior to a second fresh in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycle on live birth rates in women with a failed first IVF/ICSI cycle. METHOD: Multicenter randomized controlled trial in Dutch academic and non-academic hospitals. A total of 900 women will be included of whom half will undergo an endometrial scratch in the luteal phase of the cycle prior to controlled ovarian hyperstimulation using an endometrial biopsy catheter. The primary endpoint is the live birth rate after the 2nd fresh IVF/ICSI cycle. Secondary endpoints are costs, cumulative live birth rate (after the full 2nd IVF/ICSI cycle and over 12 months of follow-up); clinical and ongoing pregnancy rate; multiple pregnancy rate; miscarriage rate and endometrial tissue parameters associated with implantation failure. DISCUSSION: Multiple studies have been performed to investigate the effect of endometrial scratching on live birth rates in women undergoing IVF/ICSI cycles. Due to heterogeneity in both the method and population being scratched, it remains unclear which group of women will benefit from the procedure. The SCRaTCH trial proposed here aims to investigate the effect of endometrial scratching prior to controlled ovarian hyperstimulation in a large group of women undergoing a second IVF/ICSI cycle. TRIAL REGISTRATION: NTR 5342 , registered July 31st, 2015. PROTOCOL VERSION: Version 4.10, January 4th, 2017

IVF outcomes are associated with biomarkers of the homocysteine pathway in monofollicular fluid

Background: Maternal hyperhomocysteinemia is detrimental for reproduction, but the effects on embryo quality are unknown. The aim of this study was to investigate whether biomarkers of the homocysteine pathway are associated with in vitro fertilization (IVF) outcome. METHODS: In a prospective study, we investigated biomarkers of the homocysteine pathway for associations with embryo quality and biochemical pregnancy in women undergoing IVF or intracytoplasmic sperm injection treatment (n = 181). In the treatment cycle, blood and monofollicular fluid samples were collected for determination of folate, cobalamin and total homocysteine (tHcy) concentrations. Results: Of all the women in the study, 67% used folic acid supplements. In blood, a significant correlation was established between high cobalamin and better embryo quality [standardized adjusted regression coefficient: -0.17, 95% confidence interval (CI): -0.30, -0.01]. In monofollicular fluid of non-supplemented women, high cobalamin correlated with better embryo quality (estimate: -0.87; 95% CI: -1.68, -0.06), whereas high tHcy resulted in poor embryo quality (estimate: 1.01; 95% CI: 0.08, 1.95). However, in monofollicular fluid of supplemented women, high tHcy correlated with better embryo quality (estimate: -0.58; 95% CI: -1.12, -0.04). In the total group, a 2-fold increase of monofollicular fluid folate corresponded with a 3.3 times higher chance (95% CI: 1.09, 9.71) of achieving pregnancy. Conclusions: An optimal homocysteine pathway in follicular fluid is associated with a better embryo quality and chance of pregnancy.<br/

Endometrial scratching in women with implantation failure after a first IVF/ICSI cycle; does it lead to a higher live birth rate? The SCRaTCH study : A randomized controlled trial (NTR 5342)

Background: Success rates of assisted reproductive techniques (ART) are approximately 30%, with the most important limiting factor being embryo implantation. Mechanical endometrial injury, also called 'scratching', has been proposed to positively affect the chance of implantation after embryo transfer, but the currently available evidence is not yet conclusive. The primary aim of this study is to determine the effect of endometrial scratching prior to a second fresh in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycle on live birth rates in women with a failed first IVF/ICSI cycle. Method: Multicenter randomized controlled trial in Dutch academic and non-academic hospitals. A total of 900 women will be included of whom half will undergo an endometrial scratch in the luteal phase of the cycle prior to controlled ovarian hyperstimulation using an endometrial biopsy catheter. The primary endpoint is the live birth rate after the 2nd fresh IVF/ICSI cycle. Secondary endpoints are costs, cumulative live birth rate (after the full 2nd IVF/ICSI cycle and over 12months of follow-up); clinical and ongoing pregnancy rate; multiple pregnancy rate; miscarriage rate and endometrial tissue parameters associated with implantation failure. Discussion: Multiple studies have been performed to investigate the effect of endometrial scratching on live birth rates in women undergoing IVF/ICSI cycles. Due to heterogeneity in both the method and population being scratched, it remains unclear which group of women will benefit from the procedure. The SCRaTCH trial proposed here aims to investigate the effect of endometrial scratching prior to controlled ovarian hyperstimulation in a large group of women undergoing a second IVF/ICSI cycle. Trial registration: NTR 5342 , registered July 31st, 2015. Protocol version: Version 4.10, January 4th, 2017