Compliance to the recommended use of folic acid supplements for women in Sweden is higher among those under treatment for infertility than among fertile controls and is also related to socioeconomic status and lifestyle

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.

Association between folic acid use during pregnancy and gestational diabetes mellitus: Two population-based Nordic cohort studies

Introduction

Inconsistent results have been reported on the association between folic acid use in pregnancy and risk of GDM. The aim of this study was to estimate the association between folic acid use and GDM in two population-based Nordic cohorts.

Material and methods

Two cohort studies were conducted using data from the national population registers in Norway (2005–2018, n = 791,709) and Sweden (2006–2016, n = 1,112,817). Logistic regression was used to estimate the associations between GDM and self-reported folic acid use and prescribed folic acid use, compared to non-users, adjusting for covariates. To quantify how potential unmeasured confounders may affect the estimates, E-values were reported. An exposure misclassification bias analysis was also performed.

Results

In Norwegian and Swedish cohorts, adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for maternal self-reported folic acid use were 1.10 (1.06–1.14) and 0.89 (0.85–0.93), with E-values of 1.43 (1.31) and 1.50 (1.36), respectively. For prescribed folic acid use, ORs were 1.33 (1.15–1.53) and 1.56 (1.41–1.74), with E-values of 1.99 (1.57) and 2.49 (2.17), in Norway and Sweden respectively.

Conclusions

The slightly higher or lower odds for GDM in self-reported users of folic acid in Norway and Sweden respectively, are likely not of clinical relevance and recommendations for folic acid use in pregnancy should remain unchanged. The two Nordic cohorts showed different directions of the association between self-reported folic acid use and GDM, but based on bias analysis, exposure misclassification is an unlikely explanation since there may still be differences in prevalence of use and residual confounding. Prescribed folic acid is used by women with specific comorbidities and co-medications, which likely underlies the higher odds for GDM.

Drinking Water Disinfection by-Products and Congenital Malformations: A Nationwide Register-Based Prospective Study

BACKGROUND

Drinking water chlorination by-products have been associated with adverse reproductive outcomes, although the findings for congenital malformations are still inconclusive.

OBJECTIVE

We conducted a nationwide register-based prospective study to assess whether first trimester maternal exposure to the four most common trihalomethanes [total trihalomethanes (TTHM)] via municipal drinking water was associated with risk of congenital malformation among newborns.

METHODS

We included all births during 2005-2015 (live and stillbirths) of mothers residing in Swedish localities having >10,000 inhabitants, two or fewer operating water works, and sufficient municipal TTHM monitoring data. Individual maternal first trimester exposure was obtained by linking TTHM measurements to residential information, categorized into no chlorination and <5, 5-15, and >15μg TTHM/L. We also made chlorination treatment-specific analyses (exclusive use of chloramine or hypochlorite). Outcomes and covariates were obtained via linkage to health care and administrative registers. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by logistic regression.

RESULTS

Based on 623,468 births and a prevalence of congenital malformation of ∼2 cases/100 births, we observed associations between TTHM exposure in areas using chloramine and malformations of the nervous system (OR=1.82; 95% CI: 1.07, 3.12), urinary system (OR=2.06; 95% CI: 1.53, 2.78), genitals (OR=1.77; 95% CI: 1.38, 2.26), and limbs (OR=1.34; 95% CI: 1.10, 1.64), comparing the highest exposed category with the unexposed. No associations were observed in areas using exclusively hypochlorite as the primary water treatment method. By contrast, for malformations of the heart, a significant inverse association was observed only in areas using hypochlorite.

DISCUSSION

TTHM exposure was associated with the increased risk of malformations of the nervous system, urinary system, genitals, and limbs in areas exclusively using chloramine. An association between chloramine-related chlorination by-products and congenital malformations has not previously been highlighted and needs further attention. https://doi.org/10.1289/EHP9122.

Efficacy, safety and tolerability of progesterone vaginal pessaries versus progesterone vaginal gel for luteal phase support after in vitro fertilisation: a randomised controlled trial

STUDY QUESTION

Are progesterone vaginal pessaries 400 mg twice a day (bid) non-inferior to progesterone vaginal gel (90 mg) once a day (od) in the primary endpoint of clinical pregnancy rate after 38 days of luteal phase support in women undergoing in vitro fertilisation (IVF)?

SUMMARY ANSWER

Non-inferiority of progesterone vaginal pessaries 400 mg bid to progesterone 8% vaginal gel (90 mg od) was shown for clinical pregnancy rate after 38 days of luteal phase support.

WHAT IS KNOWN ALREADY

To maximise successful embryo transfer after IVF, additionally administered progesterone is used for proper endometrium transformation in the luteal phase. Vaginally administered progesterone results in adequate secretory transformation of the endometrium.

STUDY DESIGN, SIZE, DURATION

This multicentre, multinational, open, randomised, two-parallel group, non-inferiority Phase 3 clinical trial was carried out at 17 study sites in five European countries (Belgium, Bulgaria, Czech Republic, Hungary and Serbia) between October 2013 and August 2014. An interactive web response system (IWRS) was implemented for treatment allocation at the sites. Power analysis, based on the assumptions of a non-inferiority margin of −9%, a significance level of α 2.5% (one-sided), power 90%, at a reference pregnancy rate for the progesterone vaginal gel group of 30%, as well as applying a dropout rate of 10%, yielded a total number of 766 patients to be randomised.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women aged between 18 and 40 years with a clinical indication for IVF/intracytoplasmic sperm injection (ICSI) and embryo transfer were eligible to participate. The clinical pregnancy rate was assessed by fetal heart movement measured by transvaginal ultrasound at day 38 (D38) (primary endpoint) and D70. Also assessed were biochemical pregnancy rate (assessed by serum β-hCG ≥25 IU/L), clinical implantation rates at D38, patient evaluation of vaginal bleeding and discharge (assessed by diary) and adverse event (AE) incidence, severity and relationship to study medication.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 769 female patients were randomised to progesterone 400 mg vaginal pessaries bid (n = 385, 50.1%) or progesterone 90 mg vaginal gel od (n = 384, 49.9%). Patients receiving progesterone vaginal pessaries and progesterone vaginal gel were comparable in demographics, baseline characteristics and number of retrieved oocytes. In the full analysis set (FAS; n = 369 progesterone vaginal pessaries and n = 368 progesterone vaginal gel), clinical pregnancy rates on D38 were 38.3% for progesterone vaginal pessaries and 39.9% for progesterone vaginal gel. In the per protocol analysis set (PP; n = 357 progesterone vaginal pessaries and n = 356 progesterone vaginal gel), clinical pregnancy rates on D38 were 38.1% for progesterone vaginal pessaries and 40.4% for progesterone vaginal gel. For the differences in pregnancy rates between the progesterone vaginal pessaries group and the progesterone vaginal gel, the lower limit of the 97.5% CI was −8.6 and −9.5% for the FAS and PP datasets, respectively. The original prespecified non-inferiority margin of −9% was thus met in the FAS dataset but was marginally below this in the PP dataset. However, the pregnancy rate of the comparator was higher than the anticipated rate of 30%, and a predetermined logistic regression model including treatment group, country and age group effects without interaction terms showed non-inferiority of progesterone vaginal pessaries to progesterone vaginal gel for both the FAS and PP populations, in that the lower limits of the 95% CIs were above 0.7 for both analyses. As a result of this, the relevant authorities accepted to widen the acceptable non-inferiority margin to −10%, and as such both the FAS and PP populations succeeded in showing non-inferiority. Biochemical pregnancy and clinical implantation rates were comparable for both treatments. Both treatment groups showed similar high compliance throughout the study, and the safety profiles were also comparable between the groups. Drug-related AEs occurred with frequencies of 15.1% with progesterone vaginal pessaries and 14.4% with progesterone vaginal gel.

LIMITATIONS, REASONS FOR CAUTION

Clinical pregnancy rate is a surrogate for the outcome of live birth rate.

WIDER IMPLICATIONS OF THE FINDINGS

Progesterone 400 mg pessaries bid for luteal phase support is an effective, safe and tolerable treatment option for women undergoing IVF during ART.

STUDY FUNDING/COMPETING INTEREST(S)

This work was funded by Actavis Group PTC ehf., Iceland, part of Teva Pharmaceuticals, and by L.D. Collins & Co. Ltd. Gedeon Richter plc has recently entered into a license and distribution agreement to commercialise the vaginal pessaries in the European Union (except Ireland/UK). The progesterone vaginal pessaries studied are now marketed as Cyclogest®, Amelgen®, Cyclovita®, Luteum and Cygest® throughout the EU, Asia and Middle East & North Africa. The competing interests are as follows. H.S.: employee of Gedeon Richter plc/PregLem S.A. C.K.: consultant to L.D. Collins & Co. Ltd and received consulting fees for work performed. T.D.H.: at the initiation and completion of this study, full professor at KU Leuven and Head of Leuven University Fertility Center at the University Hospital Gasthuisberg, Leuven, Belgium. In October 2015, T.D.H. became vice president of Global Medical Affairs Fertility at the pharmaceutical company Merck—marketing authorisation holder of the Progesterone vaginal gel (Crinone®)—and has remained a part-time professor at KU Leuven (Belgium) and adjunct professor at Yale University (New Haven, CT, USA). T.B.M.: at the initiation and completion of this study, employee of Actavis Group PTC ehf. I.K.: consultant to Actavis, later TEVA and received consulting fees for work performed. S.H.: at the initiation and completion of this study, employee of Actavis Group PTC ehf.

Trial registration number

EudraCT number 2013-001105-81

Trial registration date

2 July 2013

Date of first patient’s enrolment

9 October 2013

Maternal blood folate status during early pregnancy and occurrence of autism spectrum disorder in offspring: a study of 62 serum biomarkers

BACKGROUND

Autism spectrum disorder (ASD) evolves from an interplay between genetic and environmental factors during prenatal development. Since identifying maternal biomarkers associated with ASD risk in offspring during early pregnancy might result in new strategies for intervention, we investigated maternal metabolic biomarkers in relation to occurrence of ASD in offspring using both univariate logistic regression and multivariate network analysis.

METHODS

Serum samples from 100 women with an offspring diagnosed with ASD and 100 matched control women with typically developing offspring were collected at week 14 of pregnancy. Concentrations of 62 metabolic biomarkers were determined, including amino acids, vitamins (A, B, D, E, and K), and biomarkers related to folate (vitamin B₉) metabolism, lifestyle factors, as well as C-reactive protein (CRP), the kynurenine-tryptophan ratio (KTR), and neopterin as markers of inflammation and immune activation.

RESULTS

We found weak evidence for a positive association between higher maternal serum concentrations of folate and increased occurrence of ASD (OR per 1 SD increase: 1.70, 95% CI 1.22-2.37, FDR adjusted P = 0.07). Multivariate network analysis confirmed expected internal biochemical relations between the biomarkers. Neither inflammation markers nor vitamin D₃ levels, all hypothesized to be involved in ASD etiology, displayed associations with ASD occurrence in the offspring.

CONCLUSIONS

Our findings suggest that high maternal serum folate status during early pregnancy may be associated with the occurrence of ASD in offspring. No inference about physiological mechanisms behind this observation can be made at the present time because blood folate levels may have complex relations with nutritional intake, the cellular folate status and status of other B-vitamins. Therefore, further investigations, which may clarify the potential role and mechanisms of maternal blood folate status in ASD risk and the interplay with other potential risk factors, in larger materials are warranted.

Nutrition and Female Fertility: An Interdependent Correlation

Besides aging, a number of non-modifiable lifestyle-related factors, such as smoking, elevated consumption of caffeine and alcohol, stress, agonist sports, chronic exposure to environmental pollutants, and other nutritional habits exert a negative impact on a women's fertility. In particular, metabolic disorders including diabetes, obesity, and hyperlipidemia commonly associated to hypercaloric diets are suspected to affect a woman's fertility either by direct damage to oocyte health and differentiation, or by indirect interference with the pituitary-hypothalamic axis, resulting in dysfunctional oogenesis. Obese women show decreased insulin sensitivity determining persistent hyperinsulinemia, which may be involved in the pathogenesis of Polycystic Ovary Syndrome. Thus, the reduced insulin secretion induced by dietary adjustments is an attractive non-pharmacological treatment to prevent infertility, and a Mediterranean diet aimed at maintaining normal body mass may be effective in the preservation of ovarian health and physiology. Furthermore, in relation to the oxidative stress as a co-factor of defective oocyte maturation, an appropriate intake of proteins, antioxidants and methyl-donor supplements (1-Carbon Cycle) may decrease the bioavailability of toxic oxidants resulting in the protection of oocyte maturation.