Dietary factors and luteal phase deficiency in healthy eumenorrheic women

How phytochemicals influence reproductive outcomes in women receiving assisted reproductive techniques: a systematic review

CONTEXT

Over the past few years, there has been an increasing amount of scholarly literature suggesting a connection between the nutritional status of pregnant mothers and early fetal development, as well as the long-term health consequences of their offspring. Multiple studies have documented that alterations in dietary patterns prior to conception have the potential to affect the initial stages of embryonic development.

OBJECTIVES

The aim of this study was to perform a comprehensive review of the research pertaining to the correlation between phytochemicals ( specifically, polyphenols, carotenoids and phytoestrogens) and assisted reproductive technology (ART).

DATA SOURCES

PubMed, Scopus, Web of Science, and Clinical Trials databases were searched from January 1978 to March 2023.

STUDY SELECTION

This study comprised observational, randomized controlled, and cohort studies that examined the effects of phytochemicals on ART results. The study's outcomes encompass live birth rate, clinical pregnancy, and ongoing pregnancy.

DATA EXTRACTION

The assessment of study quality was conducted by 2 researchers, independently, using the Quality Criteria Checklist for Primary Research.

RESULTS

A total of 13 studies were included, of which there were 5 randomized controlled studies, 1 nonrandomized controlled study, 6 prospective cohort studies, and 1 retrospective cohort study.

CONCLUSION

This research focused on investigating the impact of phytochemicals on ART and has highlighted a dearth of articles addressing that topic. Collaboration among patients, physicians, and nutritionists is crucial for doing novel research.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023426332.

Traditional and Domestic Cooking Dramatically Reduce Estrogenic Isoflavones in Soy Foods

Soybean is a pulse which has considerable nutritional value due to its high protein, fibers and polyunsaturated fatty acid (PUFA) contents. It also contains phytoestrogenic compounds that definitely hinder its recommendation for general consumption. Contrary to ancient times, when soybeans were boiled, modern commercial soy foods can contain up to 150 mg/100g of estrogenic isoflavones. Interestingly, current estimations of isoflavone intake in the literature do not distinguish between the origins of soy food, i.e., whether it is homemade or commercial. As a result, the isoflavone exposure in Asian countries may well be overestimated. This study aims to demonstrate, based on step-by-step monitoring of isoflavones, that traditional and domestic treatments, leveraging isoflavones water-solubility, can indeed significantly reduce their content in soy foods. Indeed, when compared to commercial foods, the isoflavone content was found to be 20, 2.6, 4.5 and 9.8 times lower in "homemade" soy juice, tofu, tempeh and miso, respectively. Additionally, water soaking was found to reduce the isoflavones levels in soy-textured proteins by more than 70%. Hence, this simple process has the potential to help drastically reduce overall xenoestrogens exposure. This study could serve as a basis for establishing the isoflavones Reference Dose and issuing food safety guidelines.

Mediterranean diet and female reproductive health over lifespan: a systematic review and meta-analysis

OBJECTIVE

We conducted a systematic review and meta-analysis of the effects of Mediterranean diet on female reproductive health outcomes over the life-course.

DATA SOURCES

We searched PubMed, Embase, MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov to identify eligible studies published till February 2022. Eligible references from identified studies and review articles were also considered.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials, prospective cohort studies, or nested case-control studies examining Mediterranean diet and major female reproductive outcomes over the lifespan, including clinical outcomes from childhood to adulthood (menarche, polycystic ovary syndrome, endometriosis, and outcomes related to fertility, pregnancy, and menopause), were included for review.

METHODS

Two independent reviewers screened and performed data extraction and risk-of-bias assessment. We performed random-effects meta-analysis to obtain summary relative risks and 95% confidence intervals for major female reproductive outcomes. Subgroup analyses were performed for several pregnancy outcomes according to timing of the interventions for randomized controlled trials and timing of the dietary assessment for observational studies.

RESULTS

Thirty-two studies (9 randomized controlled trials, 22 prospective cohort studies, and 1 nested case-control study) involving 103,204 predominantly White women (>95%) were included. The pooled relative risk (95% confidence interval) comparing randomization to Mediterranean diet vs a control diet based on 7 randomized controlled trials was 0.74 (0.55-0.99) for gestational diabetes mellitus, 0.45 (0.26-0.76) for preterm birth, 0.71 (0.51-1.00) for gestational hypertension, and 0.82 (0.54-1.22) for preeclampsia; the effect sizes for preterm birth were greater in randomized controlled trials that initiated the interventions in first trimester vs after first trimester (P heterogeneity=.02). We observed inverse associations for all the above-mentioned pregnancy outcomes based on 9 cohort studies. There was suggestive evidence of favorable associations between Mediterranean diet adherence with fertility and gestational weight management. Limited studies suggested associations between higher Mediterranean diet adherence and later time to menarche and fewer vasomotor menopausal symptoms, null associations for polycystic ovary syndrome-like phenotype and pregnancy loss, and positive associations for luteal phase deficiency.

CONCLUSION

Adherence to Mediterranean diet may lower risks of adverse pregnancy outcomes among predominantly White populations. For fertility-related outcomes, available evidence supporting potential beneficial effects is suggestive yet limited. For other reproductive outcomes across the lifespan, data remains sparse.

Isoflavone Consumption and Risk of Breast Cancer: An Updated Systematic Review with Meta-Analysis of Observational Studies

RATIONALE

Epidemiological studies that focus on the relationship between dietary isoflavone intake and the risk of breast cancer still lead to inconsistent conclusions. Herein, we conducted a meta-analysis of the latest studies to explore this issue.

METHOD

We performed a systematic search using Web of Science, PubMed, and Embase from inception to August 2021. The robust error meta-regression (REMR) model and generalized least squares trend (GLST) model were used to establish dose-response relationships between isoflavones and breast cancer risk.

RESULTS

Seven cohort studies and 17 case-control studies were included in the meta-analysis, and the summary OR for breast cancer was 0.71 (95% CI 0.72-0.81) when comparing the highest to the lowest isoflavone intake. A subgroup analysis further showed that neither menopausal status nor ER status has a significant influence on the association between isoflavone intake and breast cancer risk, while the isoflavone intake doses and study design does. When the isoflavones exposure was less than 10 mg/day, no effects on breast cancer risk were detected. The inverse association was significant in the case-control studies but not in the cohort studies. In the dose-response meta-analysis of the cohort studies, we observed an inverse association between isoflavone intake and breast cancer: a 10 mg/day increase in isoflavone intake was related to reductions of 6.8% (OR = 0.932, 95% CI 0.90-0.96) and 3.2% (OR = 0.968, 95% CI 0.94-0.99) in breast cancer risk when using REMR and GLST, respectively. In the dose-response meta-analysis of the case-control studies, the inverse association for every 10 mg/day isoflavone intake was associated with breast cancer risk reductions by 11.7%.

CONCLUSION

present evidence demonstrated that taking in dietary isoflavone is helpful in reducing the breast cancer risk.

Improved Food-Processing Techniques to Reduce Isoflavones in Soy-Based Foodstuffs

Soy is a growing protein source; however, the isoflavones it contains are of concern, as they exhibit estrogenic activities whose toxicological limits might be exceeded. Reducing their concentrations to safe levels while preserving nutritional quality in soy foodstuffs is therefore a matter of public health. The main objective of this paper is to develop at pilot scale a process for isoflavones’ extraction from soybeans, and to show its feasibility and efficiency. The study was conducted by first optimizing the previously obtained laboratory treatment key factors. These data were then transposed to the pilot level. Finally, the process was adjusted to technical constraints which appeared at pilot scale: the mandatory use of drenching and the exploration of granulometry analysis. The involved steps were validated by monitoring the genistein and daidzein content variations through statistical analysis of the data of an ELISA and a Folin–Ciocalteu assay. Additionally, isoflavones’ recovery from treatment waters for their valorisation and the water cleaning by means of filtration, centrifugation and resin adsorption were carried out. The results showed that the most successful pilot treatment developed involved soybean dehulling, drenching, washing and drying and almost halved isoflavones while preserving the main nutritional characteristics. A combination of techniques led to almost complete recovery of isoflavones from process waters.

Phytoestrogens and Health Effects

Phytoestrogens are literally estrogenic substances of plant origin. Although these substances are useful for plants in many aspects, their estrogenic properties are essentially relevant to their predators. As such, phytoestrogens can be considered to be substances potentially dedicated to plant-predator interaction. Therefore, it is not surprising to note that the word phytoestrogen comes from the early discovery of estrogenic effects in grazing animals and humans. Here, several compounds whose activities have been discovered at nutritional concentrations in animals and humans are examined. The substances analyzed belong to several chemical families, i.e., the flavanones, the coumestans, the resorcylic acid lactones, the isoflavones, and the enterolignans. Following their definition and the evocation of their role in plants, their metabolic transformations and bioavailabilities are discussed. A point is then made regarding their health effects, which can either be beneficial or adverse depending on the subject studied, the sex, the age, and the physiological status. Toxicological information is given based on official data. The effects are first presented in humans. Animal models are evoked when no data are available in humans. The effects are presented with a constant reference to doses and plausible exposure.

Luteal phase support for women trying to conceive by intrauterine insemination or sexual intercourse

BACKGROUND

Ovulation induction may impact endometrial receptivity due to insufficient progesterone secretion. Low progesterone is associated with poor pregnancy outcomes.

OBJECTIVES

To assess the effectiveness and safety of luteal phase support (LPS) in infertile women trying to conceive by intrauterine insemination or by sexual intercourse.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Group Specialised Register, CENTRAL, MEDLINE, Embase, PsycINFO, LILACS, trial registries for ongoing trials, and reference lists of articles (from inception to 25 August 2021).

SELECTION CRITERIA

Randomised controlled trials (RCTs) of LPS using progestogen, human chorionic gonadotropin (hCG), or gonadotropin-releasing hormone (GnRH) agonist supplementation in IUI or natural cycle.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were live birth rate/ongoing pregnancy rate (LBR/OPR) and miscarriage.  MAIN RESULTS: We included 25 RCTs (5111 participants). Most studies were at unclear or high risk of bias. We graded the certainty of evidence as very low to low. The main limitations of the evidence were poor reporting and imprecision. 1. Progesterone supplement versus placebo or no treatment  We are uncertain if vaginal progesterone increases LBR/OPR (risk ratio (RR) 1.10, 95% confidence interval (CI) 0.81 to 1.48; 7 RCTs; 1792 participants; low-certainty evidence) or decreases miscarriage per pregnancy compared to placebo or no treatment (RR 0.70, 95% CI 0.40 to 1.25; 5 RCTs; 261 participants). There were no data on LBR or miscarriage with oral stimulation. We are uncertain if progesterone increases LBR/OPR in women with gonadotropin stimulation (RR 1.24, 95% CI 0.80 to 1.92; 4 RCTs; 1054 participants; low-certainty evidence) and oral stimulation (clomiphene citrate or letrozole) (RR 0.97, 95% CI 0.58 to 1.64; 2 RCTs; 485 participants; low-certainty evidence). One study reported on OPR in women with gonadotropin plus oral stimulation; the evidence from this study was uncertain (RR 0.73, 95% CI 0.37 to 1.42; 1 RCT; 253 participants; low-certainty evidence). Given the low certainty of the evidence, it is unclear if progesterone reduces miscarriage per clinical pregnancy in any stimulation protocol (RR 0.68, 95% CI 0.24 to 1.91; 2 RCTs; 102 participants, with gonadotropin; RR 0.67, 95% CI 0.30 to 1.50; 2 RCTs; 123 participants, with gonadotropin plus oral stimulation; and RR 0.53, 95% CI 0.25 to 1.14; 2 RCTs; 119 participants, with oral stimulation). Low-certainty evidence suggests that progesterone in all types of ovarian stimulation may increase clinical pregnancy compared to placebo (RR 1.38, 95% CI 1.10 to 1.74; 7 RCTs; 1437 participants, with gonadotropin; RR 1.40, 95% CI 1.03 to 1.90; 4 RCTs; 733 participants, with gonadotropin plus oral stimulation (clomiphene citrate or letrozole); and RR 1.44, 95% CI 1.04 to 1.98; 6 RCTs; 1073 participants, with oral stimulation). 2. Progesterone supplementation regimen  We are uncertain if there is any difference between 300 mg and 600 mg of vaginal progesterone for OPR and multiple pregnancy (RR 1.58, 95% CI 0.81 to 3.09; 1 RCT; 200 participants; very low-certainty evidence; and RR 0.50, 95% CI 0.05 to 5.43; 1 RCT; 200 participants, very low-certainty evidence, respectively). No other outcomes were reported for this comparison. There were three different comparisons between progesterone regimens. For OPR, the evidence is very uncertain for intramuscular (IM) versus vaginal progesterone (RR 0.59, 95% CI 0.34 to 1.02; 1 RCT; 225 participants; very low-certainty evidence); we are uncertain if there is any difference between oral and vaginal progesterone (RR 1.25, 95% CI 0.70 to 2.22; 1 RCT; 150 participants; very low-certainty evidence) or between subcutaneous and vaginal progesterone (RR 1.05, 95% CI 0.54 to 2.05; 1 RCT; 246 participants; very low-certainty evidence). We are uncertain if IM or oral progesterone reduces miscarriage per clinical pregnancy compared to vaginal progesterone (RR 0.75, 95% CI 0.43 to 1.32; 1 RCT; 81 participants and RR 0.58, 95% CI 0.11 to 3.09; 1 RCT; 41 participants, respectively). Clinical pregnancy and multiple pregnancy were reported for all comparisons; the evidence for these outcomes was very uncertain. Only one RCT reported adverse effects. We are uncertain if IM route increases the risk of adverse effects when compared with the vaginal route (RR 9.25, 95% CI 2.21 to 38.78; 1 RCT; 225 participants; very low-certainty evidence). 3. GnRH agonist versus placebo or no treatment  No trials reported live birth. The evidence is very uncertain about the effect of GnRH agonist in ongoing pregnancy (RR 1.10, 95% CI 0.70 to 1.74; 1 RCT; 291 participants, very low-certainty evidence), miscarriage per clinical pregnancy (RR 0.73, 95% CI 0.26 to 2.10; 2 RCTs; 79 participants, very low-certainty evidence) and clinical pregnancy (RR 1.00, 95% CI 0.68 to 1.47; 2 RCTs; 340 participants; very low-certainty evidence), and multiple pregnancy (RR 0.28, 95% CI 0.11 to 0.70; 2 RCTs; 126 participants). 4. GnRH agonist versus vaginal progesterone  The evidence for the effect of GnRH agonist injection on clinical pregnancy is very uncertain (RR 1.00, 95% CI 0.51 to 1.95; 1 RCT; 242 participants). 5. HCG injection versus no treatment  The evidence for the effect of hCG injection on clinical pregnancy (RR 0.93, 95% CI 0.40 to 2.13; 1 RCT; 130 participants) and multiple pregnancy rates (RR 1.03, 95% CI 0.22 to 4.92; 1 RCT; 130 participants) is very uncertain. 6. Luteal support in natural cycle No study evaluated the effect of LPS in natural cycle. We could not perform sensitivity analyses, as there were no studies at low risk of selection bias and not at high risk in other domains.

AUTHORS' CONCLUSIONS

We are uncertain if vaginal progesterone supplementation during luteal phase is associated with a higher live birth/ongoing pregnancy rate. Vaginal progesterone may increase clinical pregnancy rate; however, its effect on miscarriage rate and multiple pregnancy rate is uncertain. We are uncertain if IM progesterone improves ongoing pregnancy rates or decreases miscarriage rate when compared to vaginal progesterone. Regarding the other reported comparisons, neither oral progesterone nor any other medication appears to be associated with an improvement in pregnancy outcomes (very low-certainty evidence).

The role of soy and soy isoflavones on women's fertility and related outcomes: an update

Soy is a key food in human nutrition. It is widely used in eastern traditional cuisine and it has recently diffused among self-conscious and vegetarian diets. The success of soy mainly depends on versatility and supposed healthy properties of soy foods and soy components. Meanwhile, the possible influence on endocrine system, in particular by isoflavones, raised concerns among some researchers. The present paper aims to conduct a review of available data on the effect of soy, soy foods and soy components on women's fertility and related outcomes. Eleven interventional studies, eleven observational studies and one meta-analysis have been selected from the results of queries. A weak, not clinically relevant effect has been highlighted on cycle length and hormonal status. However, a suggestive positive influence has been shown among women with fertility issues and during assisted reproductive technologies. Overall, soy and soy components consumption do not seem to perturb healthy women's fertility and can have a favourable effect among subjects seeking pregnancy. However, because of the paucity of studies exploring the impact of soy intake on women's fertility, as well as the limited population sample size, the frequently incomplete specimens’ collection to investigate all cycle phases and the insufficient characterisation of participants, the evidence is suggestive and it needs further in-depth research taking into account all these aspects.

Food insecurity and adverse pregnancy outcomes among rural Malawian women

OBJECTIVE

To investigate whether food insecurity is associated with adverse pregnancy outcomes such as miscarriage, stillbirth, and neonatal mortality among women in rural Malawi.

METHODS

We analyzed data from the baseline (July 2014 to February 2015) and follow-up (January 2018 to May 2018) waves of a longitudinal study of reproductive-age women in rural Malawi. We sampled women from villages from the catchment area of a community hospital in rural Lilongwe district of Malawi using stratified cluster sampling. We classified women as food secure or insecure at baseline. Using unadjusted and adjusted log-binomial models, we used baseline data to examine the cross-sectional association between food insecurity and ever experiencing an adverse pregnancy outcome. We used baseline and follow-up data to assess the longitudinal association between food insecurity and experiencing a new adverse pregnancy outcome during follow-up. In a subgroup analysis, we repeated the longitudinal analysis after restricting the sample to women who had no adverse pregnancy outcomes at baseline.

RESULTS

We observed no significant cross-sectional association between baseline food insecurity and ever experiencing an adverse pregnancy outcome (adjusted prevalence ratio: 1.09; 95% confidence interval [CI]: 0.78-1.53). Baseline food insecurity was not associated with experiencing a new adverse pregnancy outcome during follow-up (adjusted risk ratio [aRR]: 1.14, 95% CI: 0.60-2.20) or in the subgroup analysis (aRR: 1.52, 95% CI: 0.78-2.96).

CONCLUSIONS

While food insecurity is a critical issue, in this cohort of rural Malawian women, food insecurity was not associated with adverse pregnancy outcomes.

Estrogenic Pastures: A Source of Endocrine Disruption in Sheep Reproduction

Phytoestrogens can impact on reproductive health due to their structural similarity to estradiol. Initially identified in sheep consuming estrogenic pasture, phytoestrogens are known to influence reproductive capacity in numerous species. Estrogenic pastures continue to persist in sheep production systems, yet there has been little headway in our understanding of the underlying mechanisms that link phytoestrogens with compromised reproduction in sheep. Here we review the known and postulated actions of phytoestrogens on reproduction, with particular focus on competitive binding with nuclear and non-nuclear estrogen receptors, modifications to the epigenome, and the downstream impacts on normal physiological function. The review examines the evidence that phytoestrogens cause reproductive dysfunction in both the sexes, and that outcomes depend on the developmental period when an individual is exposed to phytoestrogen.

Effect of a dietary and exercise intervention in women with overweight and obesity undergoing fertility treatments: protocol for a randomized controlled trial

BACKGROUND

Distinct molecular, inflammatory, and metabolic signatures are present in oocytes and follicular fluid derived from women with obesity when compared to those derived from normal weight women, which suggest existing signals that may program future offspring for metabolic diseases. This study aims to assess the feasibility and efficacy of a peri-conception nutrition and exercise intervention on mitigating obesity-associated changes in oocyte gene expression profiles and follicular fluid metabolites.

METHODS

This single blinded randomized control trial will include 120 women with a BMI of 25-45 kg/m², ≥21 years of age, and undergoing in vitro fertilization (IVF) treatments. Participants will be randomized to standard of care (N = 60) or an intervention group (N = 60) in a block design by polycystic ovary syndrome status. The intervention will combine a dietary component (Mediterranean meal plan) with exercise prescription following the Physical Activity Guidelines for Americans. Participants will be assessed pre- and post-intervention. The standard of care group will be offered to join the intervention group if the IVF treatments are unsuccessful as a cross over design. Recruitment is anticipated to start in July of 2021. Primary outcomes will include single oocyte gene expression profiles and follicular fluid metabolites. Mann-Whitney U nonparametric tests will be used to assess potential differences for each stratum. Follicular fluid and serum metabolites will be analyzed using a one-factor Analysis of Covariance (ANCOVA) at four levels, pair-wise comparisons using Tukey-Kramer post-hoc tests will be used to identify groups whose means differ significantly while retaining the family-wise error rate at 5%. When the design is balanced, two-way Analysis of Variance (ANOVA), or non-parametric Friedman test will be used in data analysis. Additionally, general linear models and ANCOVA may be used to control for covariates. Significance will be set at p < 0.05. Findings will be disseminated via peer-reviewed manuscripts and presentations at scientific conferences.

DISCUSSION

This study will provide novel data and key information on the impact of a dietary and exercise intervention on oocyte gene expression and follicular fluid content. Results will demonstrate the potential of such intervention in mitigating obesity-induced changes in oocyte gene expression and follicular fluid metabolites.

TRIAL REGISTRATION

ClinicalTrials.gov ( NCT04273048 ): submitted November 13, 2019; posted February 17, 2020.

Neither soyfoods nor isoflavones warrant classification as endocrine disruptors: a technical review of the observational and clinical data

Soybeans are a rich source of isoflavones, which are classified as phytoestrogens. Despite numerous proposed benefits, isoflavones are often classified as endocrine disruptors, based primarily on animal studies. However, there are ample human data regarding the health effects of isoflavones. We conducted a technical review, systematically searching Medline, EMBASE, and the Cochrane Library (from inception through January 2021). We included clinical studies, observational studies, and systematic reviews and meta-analyses (SRMA) that examined the relationship between soy and/or isoflavone intake and endocrine-related endpoints. 417 reports (229 observational studies, 157 clinical studies and 32 SRMAs) met our eligibility criteria. The available evidence indicates that isoflavone intake does not adversely affect thyroid function. Adverse effects are also not seen on breast or endometrial tissue or estrogen levels in women, or testosterone or estrogen levels, or sperm or semen parameters in men. Although menstrual cycle length may be slightly increased, ovulation is not prevented. Limited insight could be gained about possible impacts of in utero isoflavone exposure, but the existing data are reassuring. Adverse effects of isoflavone intake were not identified in children, but limited research has been conducted. After extensive review, the evidence does not support classifying isoflavones as endocrine disruptors.

Dietary Advanced Glycation End Products (AGEs) could alter ovarian function in mice

Nutrition is an important source of exogenous AGEs and thermally processed foods present in western-style diets contain a large amount of these pro-inflammatory AGEs. Additionally, the intake of dietary AGEs could upregulate ovarian gene expression of inflammatory macrophage markers. The objective of this study was to investigate the effect of diet rich in AGEs on estrous cyclicity and ovarian function in a mouse model. Six-week old C57BL/6 J female mice were randomly subjected to either a diet low in AGEs (L-AGE) or a diet high in AGEs (H-AGE) for a total of 13 weeks. Experiments performed included daily vaginal smears to assess estrous cyclicity, ovarian superovulation with gonadotropins to assess the number of oocytes released, whole ovarian tissue mRNA quantification by RT-PCR to quantify genes involved in folliculogenesis, steroidogenesis, and macrophage markers, and ovarian morphology for follicle count. Outcome measures included estrous cyclicity, number of oocytes following superovulation, expression of genes involved in folliculogenesis, steroidogenesis, and macrophage infiltration as well as the number of primordial, primary, secondary, antral follicles and corpora lutea. Compared to mice on L-AGE diet, mice on H-AGE spent significantly longer time in the diestrus phase, had similar number of oocytes released following ovarian superovulation, and showed significant alterations in genes involved in steroidogenesis (increase in Star mRNA expression levels) and folliculogenesis (increase in Gdf-9 and Fshr mRNA expression levels). Mouse macrophage marker F4/80 mRNA expression was upregulated in mice on H-AGE diet compared to mice on L-AGE diet. Finally, mice on H-AGE diet had significantly fewer corpora lutea in their ovaries. These results indicate that the ingestion of high amounts of dietary AGEs could disrupt folliculogenesis and steroidogenesis that might lead to abnormal estrous cyclicity. Intake of dietary AGEs could also upregulate ovarian gene expression of inflammatory macrophage markers.

Novel approach using serum progesterone as a triage to guide management of patients with threatened miscarriage: a prospective cohort study

Threatened miscarriage is a common gynaecological emergency, with up to 25% of women eventually progressing to spontaneous miscarriage. The uncertainty of pregnancy outcomes results in significant anxiety. However, there is currently no acceptable framework for triaging patients presenting with threatened miscarriage. We aim to evaluate the efficacy and safety of a novel clinical protocol using a single serum progesterone level to prognosticate and guide management of patients with threatened miscarriage. 1087 women presenting with threatened miscarriage were enrolled in the study. The primary outcome was spontaneous miscarriage by 16 weeks’ gestation. Among the 77.9% (847/1087) of study participants with serum progesterone ≥ 35 nmol/L who were not treated with oral dydrogesterone, the miscarriage rate was 9.6% (81/847). This did not differ significantly from the 8.5% (31/364) miscarriage rate observed in our prior studies; p = 0.566. Among women with serum progesterone < 35 nmol/L who were treated with dydrogesterone, the miscarriage rate was 70.8% (170/240). Our novel clinical triage protocol using a single serum progesterone level allowed both effective risk stratification and a reduction in progestogen use with no significant adverse pregnancy outcomes. This protocol, based on a single serum progesterone cutoff, can be readily adapted for use in other healthcare institutions.

Dietary phytoestrogen intakes of adult women are not strongly related to fecundability in 2 preconception cohort studies

BACKGROUND

Phytoestrogens are plant-derived hormonally active compounds found in soy, cruciferous vegetables, nuts, and seeds. Although phytoestrogens have been associated with altered endogenous hormonal activity, luteal phase deficiency, and reduced endometrial decidualization, the literature reporting examinations of phytoestrogen intake and fertility presents mixed findings.

OBJECTIVES

We sought to evaluate prospectively the association between dietary phytoestrogen intake (isoflavones, lignans, and coumestans) and fecundability, the per-cycle probability of conception, in 2 cohorts of women planning pregnancy.

METHODS

Pregnancy Study Online (PRESTO) and Snart Foraeldre (SF) are parallel web-based preconception cohort studies of women from North America and Denmark, respectively, who are trying to conceive. Participants complete an online baseline questionnaire on sociodemographic, lifestyle, and medical factors. We ascertained intake of individual phytoestrogens from validated FFQs. We measured fecundability using data on menstruation and pregnancy status from bimonthly follow-up questionnaires. We analyzed data from 4880 PRESTO and 2898 SF female study participants who had been attempting conception for ≤6 cycles at study entry. We used proportional probabilities regression models to estimate fecundability ratios (FRs) and 95% CIs.

RESULTS

Phytoestrogen intake varied across cohorts, yet was associated with higher socioeconomic status and healthier behaviors in both cohorts. After adjustment for potential confounders, phytoestrogen intake was not substantially associated with fecundability in either cohort. We observed some evidence of improved fecundability with increasing isoflavone intake among women age ≥30 years in PRESTO (FR: 1.12; 95% CI: 0.94, 1.34, for comparison of ≥90th with <25th percentile intake) and SF (corresponding FR: 1.19; 95% CI: 0.92, 1.55). Lignan intake was associated with slightly increased fecundability in SF (FR for comparison of 75th to 90th with <25th percentile: 1.10; 95% CI: 0.96, 1.26), but decreased fecundability in PRESTO (FR for comparison of ≥90th with <25th percentile: 0.83; 95% CI: 0.72, 0.97).

CONCLUSIONS

We did not observe strong associations between phytoestrogen intake and prospectively-measured fecundability among North American or Danish pregnancy planners.

The Impact of Preconceptional Multiple-Micronutrient Supplementation on Female Fertility

In industrialized countries, fertility has declined in recent years to the lowest recorded levels. Identifying modifiable factors that influence human fertility, such as diet, is therefore of major clinical and public health relevance. Micronutrient status is a modifiable risk factor that may have an impact on female fertility, as essential vitamins and minerals have important roles in the physiological processes that are involved. Adequate levels are important for oocyte quality, maturation, fertilization, and implantation, whereas antioxidants are vital to reduce oxidative stress, a process known to impair fertility. In women who are diagnosed as infertile, lower than recommended levels of certain micronutrients have been reported. A similar scenario has been found in a proportion of women of childbearing age in general, some of whom may be struggling to conceive. Supplementation studies with multiple micronutrients are still scarce, but the literature suggests that supplementation before conception can help restore micronutrient status to recommended levels and reduce oxidative stress when antioxidants are included. Overall, supplementation has a small but beneficial effect on fertility in healthy and infertile women, including a shorter time to pregnancy and an increased chance of becoming pregnant. Nevertheless, many studies are small or observational, and adequately powered randomized controlled trials of supplementation with multiple micronutrients are necessary to confirm any definite effects on fertility. This review substantiates the potential benefits of micronutrient supplementation beyond the prevention of neural tube defects, the traditionally viewed value of prenatal vitamin use.

Achieving Pregnancy Using Primary Care Interventions to Identify the Fertile Window

Objective

To determine the effectiveness of achieving pregnancy with focused intercourse in the fertile window identified using natural fertility indicators.

Methods

24-cycle prospective effectiveness study.

Setting

A North American web-based fertility monitoring service.

Participants

256 North American women aged 20–43 (mean age 29.2 years) seeking to achieve pregnancy.

Intervention

Participants identified their fertile window with either electronic hormonal fertility monitoring or cervical mucus monitoring, or both, and recorded their observations on an online fertility tracking system.

Main outcome measures

Pregnancies were validated by nurses with an online self-assessed pregnancy evaluation form. Survival analysis was used to determine pregnancy rates.

Results

There were 150 pregnancies among the 256 participants with an overall pregnancy rate of 78 per 100 women over 12 menstrual cycles. There were 54 pregnancies (68%) among the 80 women using the fertility monitor, 11 pregnancies (46%) among the 24 women using mucus monitoring, and 90 (63%) among the 143 women using both mucus and monitor. The 12-cycle pregnancy rates per 100 women were 83 (monitor group), 72 (mucus group), and 75 (mucus and monitor group). Pregnancy rates reached 100% at 24 cycles of use for those women using the hormonal fertility monitor.

Conclusion

Use of the hormonal fertility monitor alone seems to offer the best natural estimate of the fertile phase of the menstrual cycle for women wishing to achieve a pregnancy. Focusing intercourse through 24 menstrual cycles can be beneficial for achieving pregnancy.

Prospective evaluation of luteal phase length and natural fertility

OBJECTIVE

To evaluate the impact of a short luteal phase on fecundity.

DESIGN

Prospective time-to-pregnancy cohort study.

SETTING

Not applicable.

PATIENT(S)

Women trying to conceive, ages 30-44 years, without known infertility.

INTERVENTION(S)

Daily diaries, ovulation prediction testing, standardized pregnancy testing.

MAIN OUTCOME MEASURE(S)

Subsequent cycle fecundity.

RESULT(S)

Included in the analysis were 1,635 cycles from 284 women. A short luteal phase (≤11 days including the day of ovulation) occurred in 18% of observed cycles. Mean luteal phase length was 14 days. Significantly more women with a short luteal phase were smokers. After adjustment for age, women with a short luteal phase had 0.82 times the odds of pregnancy in the subsequent cycle immediately following the short luteal phase compared with women without a short luteal phase. Women with a short luteal length in the first observed cycle had significantly lower fertility after the first 6 months of pregnancy attempt, but at 12 months there was no significant difference in cumulative probability of pregnancy.

CONCLUSION(S)

Although an isolated cycle with a short luteal phase may negatively affect short-term fertility, incidence of infertility at 12 months was not significantly higher among these women.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01028365.

Risks and benefits of phytoestrogens: where are we now?

PURPOSE OF REVIEW

The estrogenic effects of genistein, as reconfirmed by the American National Toxicology Program (USA-NTP), have led to several new clinical studies being undertaken. Here, we highlight the most relevant recent data, reporting either beneficial or adverse effects.

RECENT FINDINGS

Phytoestrogens are natural molecules from edible plants exhibiting estrogenic activities. Post-USA-NTP studies investigated both human and animal reproductive and other physiological issues. These studies showed that estrogens can be either deleterious for reproduction and estrogen-dependent diseases, or beneficial for those with steroid deficiencies, that is more than 50. The specific outcome depends on exposure level and on the estrogenic status of the patients exposed. Recently, it was reported that, with the industrialization of soybean process, phytoestrogen exposure dramatically increased in both humans and cattle, whereas traditional Asian soy-food-processing empirically removed isoflavones. Phytoestrogen exposure has also become more widespread with the progressive internationalization of soybean use in human and cattle food.

SUMMARY

Phytoestrogens should be considered as modern endocrine disruptors and studied as such.