Effects of lifestyle factors on fertility: practical recommendations for modification

Downward trend in male reproductive health and fertility in Eastern Iran

This study aimed to assess the ten-year trend in semen quality among couples referred to the Infertility Center in Kerman between 2008 and 2017. The study included 2952 semen samples from men 18 to 60 years old referred to the infertility center as infertile couples living in Kerman province, Iran, whether they had normal or abnormal semen analysis. A total of 2952 sperm samples were included. Statistically significant changes were observed in semen parameters. Particularly, significant changes were observed for volume (-0.08 mL/year), sperm concentration (-2.34 (mio/mL)/year), total sperm count (-13.17 (mio/ejaculate)/year), progressive motility (-2.62%/year), non-progressive motility (-0.59%/year), immotile sperm (2.49%/year), and normal morphology (-0.134%/year). In bivariate analysis, the prevalence of oligozoospermia in this study showed a statistically significant association with age (OR = 1.019; 95% CI = 1.007-1.032; p = 0.003). Likewise, there was a statistically significant association with the year (OR = 1.087; 95% CI = 1.050-1.125; p = 0.000). Semen quality parameters showed a downtrend during the last 10 years in this study, emphasizing the importance of male reproductive health monitoring and warning public health coordinators to pay more attention to this important issue.

Predicting nutrition and environmental factors associated with female reproductive disorders using a knowledge graph and random forests

OBJECTIVE

Female reproductive disorders (FRDs) are common health conditions that may present with significant symptoms. Diet and environment are potential areas for FRD interventions. We utilized a knowledge graph (KG) method to predict factors associated with common FRDs (for example, endometriosis, ovarian cyst, and uterine fibroids).

MATERIALS AND METHODS

We harmonized survey data from the Personalized Environment and Genes Study (PEGS) on internal and external environmental exposures and health conditions with biomedical ontology content. We merged the harmonized data and ontologies with supplemental nutrient and agricultural chemical data to create a KG. We analyzed the KG by embedding edges and applying a random forest for edge prediction to identify variables potentially associated with FRDs. We also conducted logistic regression analysis for comparison.

RESULTS

Across 9765 PEGS respondents, the KG analysis resulted in 8535 significant or suggestive predicted links between FRDs and chemicals, phenotypes, and diseases. Amongst these links, 32 were exact matches when compared with the logistic regression results, including comorbidities, medications, foods, and occupational exposures.

DISCUSSION

Mechanistic underpinnings of predicted links documented in the literature may support some of our findings. Our KG methods are useful for predicting possible associations in large, survey-based datasets with added information on directionality and magnitude of effect from logistic regression. These results should not be construed as causal but can support hypothesis generation.

CONCLUSION

This investigation enabled the generation of hypotheses on a variety of potential links between FRDs and exposures. Future investigations should prospectively evaluate the variables hypothesized to impact FRDs.

Low-Dose Ionizing Radiation Exposure on Human Male Gametes: Damage or Benefit

With the improvement of medical devices for diagnosis and radiotherapy, concerns about the effects of low doses of ionizing radiation are also growing. There is no consensus among scientists on whether they might have beneficial effects on humans in certain cases or pose more risks, making the exposure unreasonable. While the damaging consequences of high-dose radiation have been known since the discovery of radioactivity, low-dose effects present a much bigger investigative challenge. They are highly specific and include radio-adaptive responses, bystander effects, and genomic instability. Current data regarding the consequences of exposure to low-dose radiation on the quality of male gametes and fertility potential are contradictory. The reports suggest two directions: indirect impact on male gametes-through spermatogenesis-or direct effects at low doses on already mature spermatozoa. Although mature gametes are used for observation in both models, they are fundamentally different, leading to varied results. Due to their unique physiological characteristics, in certain cases, exposure of spermatozoa to low-dose ionizing radiation could have positive effects. Despite the findings indicating no beneficial effects of low-dose exposure on male fertility, it is essential to research its impact on mature spermatozoa, as well.

Retrospective Analysis of Effective Management Strategies for Primary Amenorrhea of Reproductive Age in Saudi Arabia

Primary amenorrhea, the absence of menstruation by age 15, can have significant implications for reproductive health and overall well-being. This retrospective study aimed to evaluate the effectiveness of various management strategies for primary amenorrhea among women of reproductive age in Saudi Arabia. Medical records of 63 eligible patients from 2018 to 2023 were analyzed, assessing diagnostic methods, treatment modalities, and associated outcomes. The findings revealed that hormonal therapy was the most commonly employed management strategy (50.0%) and demonstrated the highest rate of achieving menstrual regularity (62.5%). Surgical interventions were utilized in 28.1% of cases, with a 50.0% rate of symptom resolution. Lifestyle modifications were less frequent (21.9%) but showed a moderate rate of symptom resolution (35.7%). Logistic regression analysis identified age, underlying etiology, and management strategy as significant predictors of treatment success. Subgroup analyses highlighted the efficacy of hormonal therapy and lifestyle modifications for genetic etiologies, while surgical interventions were more effective for anatomical causes. The study underscores the importance of a comprehensive diagnostic approach and personalized treatment plans tailored to individual patient characteristics. Despite limitations, the findings contribute to the understanding of optimal management strategies for primary amenorrhea and emphasize the need for multidisciplinary collaboration in addressing this complex condition.

Do Popular Diets Impact Fertility?

Infertility affects 15% of the population in developed countries, and its prevalence is increasing. Fertility can be influenced by different factors. Although key factors like maternal age cannot be changed, there is growing evidence that other modifiable factors, such as diet, can have an impact on fertility. Diet has become increasingly important in recent years for a number of reasons: the new trend toward a healthy lifestyle, the higher prevalence of certain digestive disorders, a lack of time that leads people to consume more prepared and processed food, and personal choice to not eat meat, among others. To meet these needs, several diets have recently become popular, such as the Mediterranean diet, known as the gold standard of health; the DASH diet, known for preventing hypertension; the Western diet, characterized by processed food; the ketogenic diet, characterized by low carbohydrate intake; and the vegetarian diet, which is the choice for people who do not eat meat or animal by-products. Diets present a unique composition characterized by the presence or absence of specific nutrients, which have also been associated with male and female fertility individually. This review assesses the impact of these diets and of macro- and micronutrients on both female and male fertility.

Towards a more effective REACH legislation in protecting human health

There is growing evidence indicating the substantial contribution of man-made products to an increase in the risk of diseases of civilization. In this article, the Belgian Scientific Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) Committee gives a critical view on the working of REACH. The current regulatory framework needs to further evolve taking into account data generated using modern science and technology. There is a need for improved assessment process not only before but also after entering the market. Objectivity, transparency, and the follow-up after market access can be optimized. Additionally, no guidance documents exist for regulation of mixture effects. Further, the lengthiness before regulatory action is a big concern. Decision-making often takes several years leading to uncertainties for both producers and end users. A first proposed improvement is the implementation of independent toxicity testing, to assure objectivity, transparency, and check and improve compliance. A "no data, no market" principle could prevent access of hazardous chemicals to the market. Additionally, the introduction of novel testing could improve information on endpoints such as endocrine disrupting abilities, neurotoxicity, and immunotoxicity. An adapted regulatory framework that integrates data from different sources and comparing the outputs with estimates of exposure is required. Fast toxicology battery testing and toxicokinetic testing could improve speed of decision-making. Hereby, several improvements have been proposed that could improve the current REACH legislation.

The Impact of Lifestyle on the Secondary Sex Ratio: A Review

The secondary sex ratio (SSR), indicating the ratio of male to female live births, has garnered considerable attention within the realms of reproductive biology and public health. Numerous factors have been posited as potential trendsetters of the SSR. Given the extensive research on the impact of daily behaviors and habits on individuals' reproductive health, there is a plausible suggestion that lifestyle choices may also influence the SSR. By synthesizing the existing literature on the current research field, this comprehensive review indicates that an elevated SSR has been associated with an increased intake of fatty acids and monosaccharides, proper nutrition, higher educational levels, financial prosperity, and favorable housing conditions. On the other hand, a decreased SSR may be linked to undernutrition, socioeconomic disparities, and psychological distress, aligning with the Trivers-Willard hypothesis. Occupational factors, smoking habits, and cultural beliefs could also contribute to trends in the SSR. Our review underscores the significance of considering the aforementioned factors in studies examining the SSR and emphasizes the necessity for further research to unravel the mechanisms underpinning these connections. A more profound comprehension of SSR alterations due to lifestyle holds the potential to adequately develop public health interventions and healthcare strategies to enhance reproductive health and overall well-being.

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.

The Impact of Stress and Social Determinants on Diet in Cardiovascular Prevention in Young Women

The prevention of cardiovascular diseases is a fundamental pillar for reducing morbidity and mortality caused by non-communicable diseases. Social determinants, such as socioeconomic status, education, neighborhood, physical environment, employment, social support networks, and access to health care, play a crucial role in influencing health outcomes and health inequities within populations. Social determinants and stress in women are interconnected factors that can significantly impact women's health and well-being. Pregnancy is a good time to engage young women and introduce them to beneficial behaviors, such as adopting essential life skills, especially diet, and learning stress management techniques. Stress influences diet, and women are more likely to engage in unhealthy eating behaviors such as emotional eating or coping with stress with food. Strong action is needed to improve women's lifestyle starting at a young age considering that this lays the foundation for a lower cardiovascular risk in adults and the elderly. The objective of this review is to examine cardiovascular primary prevention in young healthy women, focusing particularly on unresolved issues and the influence of social determinants, as well as the correlation with stressors and their influence on diet.

Validity and reliability study of the Cardiff Fertility Knowledge Scale in Turkish

AIM

This study aims to determine the Turkish validity and reliability of the Cardiff Fertility Knowledge Scale.

METHODS

This methodological research was conducted between April and December 2022 with 302 married individuals at a health center in Kocaeli province, Turkey. Research data were collected using a Personal Information Form and the Cardiff Fertility Knowledge Scale. Content construct and face validity, item analysis, factor analysis, and internal consistency were used to evaluate the data.

RESULTS

The content validity index of the scale was found to be 0.97, and the Cronbach's alpha coefficient for the Turkish version was 0.68. The total scores of the top 27% group were significantly higher than the scores of the bottom 27% group (p < 0.01). As a result of the analyses, the final version of the scale consisted of 11 items and had a single factor structure, explaining 44.45% of the scale's variance.

CONCLUSION

The results of the study demonstrate that the Turkish version of the Cardiff Fertility Knowledge Scale is a valid and reliable measurement tool that can be used to assess individuals' fertility knowledge.

The impact of vegetarian diet on sperm quality, sex hormone levels and fertility: a systematic review and meta-analysis

BACKGROUND

An increasing number of people have adhered to a vegetarian diet for several years. Nowadays, the favourable effect of this dietary pattern on metabolic diseases is well established, but its impact on fertility and reproductive health as a serious health concern is not clear yet. Therefore, we aim to summarise existing evidence regarding the possible association between a vegetarian diet and fertility as measured by key indicators such as sperm quality and sex hormone levels.

METHODS

We systematically searched online databases, including PubMed, ISI, Scopus and Google Scholar, up to 1 December 2022 using relevant keywords. We included observational studies that compared semen quality, sex hormone levels and infertility in people who adhered to a vegetarian diet versus an omnivore diet. Heterogeneity between studies was assessed using I2 and Q tests. Standardised mean differences (SMD) using a random/fixed model were calculated to assess outcomes between vegetarians and omnivores in included articles.

RESULTS

Finally, out of 972 documents that were retrieved, 20 articles met our inclusion criteria, and 16 were eligible for quantitative synthesis. Results of meta-analyses showed that there were no significant differences between vegetarians and omnivores in terms of semen quality parameters, including total sperm count, total and progressive sperm motility, sperm morphology and sperm concentration. Seven studies on female sex hormone profiles were eligible for meta-analysis. The only significant difference was the lower level of plasma oestrone in vegetarians (pooled SMD: -0.56; 95% confidence interval [CI]: -1.08, -0.05; p-value = 0.03) compared to omnivores. Furthermore, our meta-analysis revealed significantly higher sex-hormone-binding globulin levels in vegetarian men than in omnivores (pooled SMD: 0.52; 95% CI: 0.18, 0.86; p-value = 0.002).

CONCLUSION

Despite the numerous health benefits of a vegetarian diet, our review suggested that there were no conclusive positive or negative associations between vegetarian diet and semen quality, sex hormone levels and infertility. Further studies are recommended to better understand vegetarian dietary pattern effect on infertility and reproductive health.

The association of Life's Simple 7 and infertility among U.S. women

Background

The Life's Simple 7 (LS7) metric is a comprehensive measure of cardiovascular health (CVH) that encompasses seven distinct risk factors and behaviors associated with cardiovascular disease (CVD). Some studies have shown an association between infertility and CVD. The present study aimed to explore the potential association between the LS7 factors and infertility.

Methods

A cross-sectional study was conducted on a sample of 3537 women aged 18-44 years from the National Health and Nutrition Examination Survey (NHANES) spanning the years 2013-2018. The LS7 metrics encompassed various factors including physical activity, smoking habits, body mass index, blood pressure levels, dietary patterns, blood glucose levels, and total cholesterol levels. We computed a 14-point LS7 score based on participants' baseline data, classifying them as "inadequate" (3-6), "average" (7-10), or "ideal" (11-14). Infertility is defined as an affirmative answer to either of two questions on the NHANES questionnaire: "Have you tried to conceive for at least one year without success?" and "Have you sought medical help for your inability to conceive?" Logistic regression was utilized to estimate odds ratios (O.R.s) and 95% confidence intervals (C.I.s).

Results

In total, 17.66% of participants were classified as individuals who reported experiencing infertility. In the continuous analysis, each one-unit increase in LS7 score was associated with a significantly decreased odds of infertility (OR=0.88 [0.77-0.89]). Analyzing the categorical representation of LS7 score, compared to individuals with poor scores, those with ideal scores exhibited a substantial 58% reduction in the odds of infertility (OR=0.42 [0.26-0.69]). Additionally, the observed interaction suggested that the influence of age on the relationship between LS7 and infertility is not consistent across different age groups (P for interaction < 0.001). Among individuals aged 35 or younger, each unit increase in LS7 score was associated with a substantial 18% (OR=0.82 [0.76-0.89]) decrease in the odds of infertility. However, in the older age group (>35), the association was attenuated and non-significant.

Conclusions

Our research suggests a significant inverse association between LS7 scores and infertility. Age demonstrated a varying impact on this relationship, with a more pronounced impact observed among individuals aged 35 or younger.

Endocrine factors associated with infertility in women: an updated review

INTRODUCTION

Infertility is defined as the inability to conceive after unprotected sexual intercourse for at least 12 consecutive months. Our objective is to present an updated narrative review on the endocrine causes of infertility in women.

AREAS COVERED

A comprehensive review was conducted using Scielo, Scopus, and EMBASE databases, comprising 245 articles. The pathophysiology of infertility in women was described, including endocrinopathies such as hypothalamic amenorrhea, hyperprolactinemia, polycystic ovary syndrome, primary ovarian insufficiency, obesity, thyroid dysfunction, and adrenal disorders. The diagnostic approach was outlined, emphasizing the necessity of hormonal studies and ovarian response assessments. Additionally, the treatment plan was presented, commencing with non-pharmacological interventions, encompassing the adoption of a Mediterranean diet, vitamin supplementation, moderate exercise, and maintaining a healthy weight. Subsequently, pharmacological treatment was discussed, focusing on the management of associated endocrine disorders and ovulatory dysfunction.

EXPERT OPINION

This comprehensive review highlights the impact of endocrine disorders on fertility in women, providing diagnostic and therapeutic algorithms. Despite remaining knowledge gaps that hinder more effective treatments, ongoing research and advancements show promise for improved fertility success rates within the next five years. Enhanced comprehension of the pathophysiology behind endocrine causes and the progress in genetic research will facilitate the delivery of personalized treatments, thus enhancing fertility rates.

Health Literacy, General Health, and Lifestyle among Infertile Men and Women in the Southeastern Iran

Background

Infertility is a growing social problem, and health literacy is one of the factors that affects infertility, thereby affecting life quality. On the other hand, lifestyle factors exert a considerable impact on reproductive capacity and general health. Against this backdrop, this study aims to determine health literacy, general health, and lifestyle in infertile people in Zahedan, Iran.

Methods

In this descriptive cross-sectional study, 86 male and 181 female participants who referred to Molod Infertility center (AliIbnAbiTalib Hospital) in Zahedan were randomly selected. Health Literacy Standard Questionnaires (HELIA), the General Health Questionnaire (GHQ), and the Miller-Smith Lifestyle Assessment Inventory (LSI) were used to collect data. In addition, data were analyzed by SPSS V.22.

Results

The participants' mean age was 30.87±7.5. Besides, 39% and 70% of the participations did not have enough health literacy and had a moderate lifestyle, respectively. In addition, the general health of 68.9% was exposed to damage. Moreover, there was a significant relationship between the three aforementioned factors, with the participants of higher levels of health literacy having had higher levels of general health and lifestyle.

Conclusion

According to the findings of this study, the infertile people's health literacy was not enough, and most of them had a moderate lifestyle. In addition, their general health was exposed to damage in most cases. Thus, it is necessary to pay attention to providing proper education and health services to infertile men and women to improve their level of health literacy and healthy fertility in order to support childbearing in the society.

Beyond body mass index: a synthesis of lifestyle factors that may influence in vitro fertilisation outcomes

There are several lifestyle factors that are thought to potentially impact in vitro fertilisation outcomes, including body mass index, smoking, alcohol consumption, caffeine, dietary patterns and physical activity. Eligibility criteria for in vitro fertilisation in England often require individuals to be non-smokers, drug free and have a body mass index <30kg/m2. Some researchers have questioned the scientific and ethical basis for the use of body mass index thresholds in fertility treatment, citing evidence that other factors may have a greater effect on the chance of success of in vitro fertilisation. This article aims to briefly synthesise the current evidence on how other factors such as smoking, alcohol, recreational drugs, smoking, caffeine, dietary patterns and physical activity may impact in vitro fertilisation outcomes.

A Dual Architecture Fusion and AutoEncoder for Automatic Morphological Classification of Human Sperm

Infertility has become a common problem in global health, and unsurprisingly, many couples need medical assistance to achieve reproduction. Many human behaviors can lead to infertility, which is none other than unhealthy sperm. The important thing is that assisted reproductive techniques require selecting healthy sperm. Hence, machine learning algorithms are presented as the subject of this research to effectively modernize and make accurate standards and decisions in classifying sperm. In this study, we developed a deep learning fusion architecture called SwinMobile that combines the Shifted Windows Vision Transformer (Swin) and MobileNetV3 into a unified feature space and classifies sperm from impurities in the SVIA Subset-C. Swin Transformer provides long-range feature extraction, while MobileNetV3 is responsible for extracting local features. We also explored incorporating an autoencoder into the architecture for an automatic noise-removing model. Our model was tested on SVIA, HuSHem, and SMIDS. Comparison to the state-of-the-art models was based on F1-score and accuracy. Our deep learning results accurately classified sperm and performed well in direct comparisons with previous approaches despite the datasets' different characteristics. We compared the model from Xception on the SVIA dataset, the MC-HSH model on the HuSHem dataset, and Ilhan et al.'s model on the SMIDS dataset and the astonishing results given by our model. The proposed model, especially SwinMobile-AE, has strong classification capabilities that enable it to function with high classification results on three different datasets. We propose that our deep learning approach to sperm classification is suitable for modernizing the clinical world. Our work leverages the potential of artificial intelligence technologies to rival humans in terms of accuracy, reliability, and speed of analysis. The SwinMobile-AE method we provide can achieve better results than state-of-the-art, even for three different datasets. Our results were benchmarked by comparisons with three datasets, which included SVIA, HuSHem, and SMIDS, respectively (95.4% vs. 94.9%), (97.6% vs. 95.7%), and (91.7% vs. 90.9%). Thus, the proposed model can realize technological advances in classifying sperm morphology based on the evidential results with three different datasets, each having its characteristics related to data size, number of classes, and color space.

Tertiary care for infertile couples: aetiological diagnoses and conventional treatment outcomes in Kisangani, Democratic Republic of the Congo

BACKGROUND

In sub-Saharan Africa, tubal factors are described as the main aetiological factors of infertility. Under these conditions, medically assisted procreation is particularly indicated. However, Assisted Reproductive Technology centres are less available. Thus, infertile couples are quickly oriented towards available alternative conventional treatments. The present study aimed to determine the aetiological factors of infertility, the outcomes of the therapeutic options offered, and the factors associated with the success of conventional treatment among infertile couples seeking tertiary care in Kisangani.

METHODS

A cross-sectional study was conducted at two tertiary health facilities in Kisangani. Infertile couples who provided consent underwent specific examinations necessary for the exploration of infertility and were treated and followed up for a minimum of 6 months. The therapeutic options that were offered were expectant attitude, medical treatment, surgical treatment or transfer to an in vitro fertilization unit. The pregnancy diagnosis was performed by ultrasound.

RESULTS

A total of 272 infertile couples underwent specific examinations, were treated and were followed up for a minimum of 6 months. Many determinant causes were mostly linked to wives rather than husbands. Overall, only 34 women among 211 who were treated became pregnant during the follow-up period; 61 couples were advised to resort to IVF or adoption, but the couples for whom expectant the attitude was indicated immediately rejected it. The patients who therapeutically succeeded at the end of the treatment were those who were younger than 35 years (OR = 2.27; 95% CI = 1.06-4.87; P = 0.017), had a duration of infertility of less than five years (OR = 6.08; 95% CI = 1.79-20.69; P = 0.001) and had secondary infertility (OR = 6.08; 95% CI = 1.79-20.69; P = 0.001).

CONCLUSION

Kisangani faces a major issue in the treatment of infertility. Treatment of patients using conventional methods is limited by the predominance of tubal factors as aetiological determinants of infertility. The low pregnancy rate found in this study provided additional evidence of this. This paper represents a serious plea to national policy-makers to encourage them to pay attention to issues surrounding infertility.

Predicting nutrition and environmental factors associated with female reproductive disorders using a knowledge graph and random forests

Objective

Female reproductive disorders (FRDs) are common health conditions that may present with significant symptoms. Diet and environment are potential areas for FRD interventions. We utilized a knowledge graph (KG) method to predict factors associated with common FRDs (e.g., endometriosis, ovarian cyst, and uterine fibroids).

Materials and Methods

We harmonized survey data from the Personalized Environment and Genes Study on internal and external environmental exposures and health conditions with biomedical ontology content. We merged the harmonized data and ontologies with supplemental nutrient and agricultural chemical data to create a KG. We analyzed the KG by embedding edges and applying a random forest for edge prediction to identify variables potentially associated with FRDs. We also conducted logistic regression analysis for comparison.

Results

Across 9765 PEGS respondents, the KG analysis resulted in 8535 significant predicted links between FRDs and chemicals, phenotypes, and diseases. Amongst these links, 32 were exact matches when compared with the logistic regression results, including comorbidities, medications, foods, and occupational exposures.

Discussion

Mechanistic underpinnings of predicted links documented in the literature may support some of our findings. Our KG methods are useful for predicting possible associations in large, survey-based datasets with added information on directionality and magnitude of effect from logistic regression. These results should not be construed as causal, but can support hypothesis generation.

Conclusion

This investigation enabled the generation of hypotheses on a variety of potential links between FRDs and exposures. Future investigations should prospectively evaluate the variables hypothesized to impact FRDs.

Current Trends on Bioengineering Approaches for Ovarian Microenvironment Reconstruction

Ovarian tissue has a unique microarchitecture and a complex cellular and molecular dynamics that are essential for follicular survival and development. Due to this great complexity, several factors may lead to ovarian insufficiency, and therefore to systemic metabolic disorders and female infertility. Techniques currently used in the reproductive clinic such as oocyte cryopreservation or even ovarian tissue transplant, although effective, have several limitations, which impair their wide application. In this scenario, mimetic ovarian tissue reconstruction comes as an innovative alternative to develop new methodologies for germ cells preservation and ovarian functions restoration. The ovarian extracellular matrix (ECM) is crucial for oocyte viability maintenance, once it acts actively in folliculogenesis. One of the key components of ovarian bioengineering is biomaterials application that mimics ECM and provides conditions for cell anchorage, proliferation, and differentiation. Therefore, this review aims at describing ovarian tissue engineering approaches and listing the main limitations of current methods for preservation and reestablishment of ovarian fertility. In addition, we describe the main elements that structure this study field, highlighting the main advances and the challenges to overcome to develop innovative methodologies to be applied in reproductive medicine. Impact Statement This review presents the main advances in the application of tissue bioengineering in the ovarian tissue reconstruction to develop innovative solutions for ovarian fertility reestablishment.

Paraben exposure and couple fecundity: a preconception cohort study

STUDY QUESTION

Is pre-conception exposure to parabens associated with fecundity in couples of childbearing age?

SUMMARY ANSWER

Paraben exposure in female partners was associated with reduced couple fecundity and anti-Müllerian hormone (AMH) might be one of the possible mediators.

WHAT IS KNOWN ALREADY

The reproductive toxicity of parabens, a class of widely used preservatives, has been suggested but evidence regarding their effects on couple fecundity is scarce.

STUDY DESIGN, SIZE, DURATION

In this couple-based prospective cohort study, a total of 884 pre-conception couples who participated in the Shanghai Birth Cohort between 2013 and 2015 were included.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Concentrations of six parabens were measured in urine samples collected from couples. Malondialdehyde, C-reactive protein, and AMH were assessed in female partners. The outcomes included couple fecundability (time-to-pregnancy, TTP) and infertility (TTP > 12 menstrual cycles). Partner-specific and couple-based models were applied to estimate the associations. The joint effect of paraben mixture on couple fecundity was estimated by quantile-based g-computation (q-gcomp). Mediation analysis was used to assess the mediating roles of oxidative stress, inflammation and ovarian reserve.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 525 couples (59.4%) conceived spontaneously. In the partner-specific model, propyl paraben (PrP), butyl paraben (BuP), and heptyl paraben (HeP) in female partners were associated with reduced fecundability (fecundability odds ratio (95% CI): 0.96 (0.94-0.98) for PrP; 0.90 (0.87-0.94) for BuP; 0.42 (0.28-0.65) for HeP) and increased risk of infertility (rate ratio (95% CI): 1.06 (1.03-1.10) for PrP; 1.14 (1.08-1.21) for BuP; 1.89 (1.26-2.83) for HeP). Similar associations were observed in the couple-based model. AMH played a significant mediation role in the association (average causal mediation effect (95% CI): 0.001 (0.0001-0.003)). Paraben exposure in male partners was not associated with couple fecundity. The joint effect of paraben mixture on couple fecundity was non-significant.

LIMITATIONS, REASONS FOR CAUTION

Self-reported pregnancy and single urine sample may lead to misclassification. The mediation analysis is limited in that levels of sex hormones were not measured. The inclusion of women with irregular menstrual cycles might affect the results. It is possible that the observed association was due to reverse causation.

WIDER IMPLICATIONS OF THE FINDINGS

This is the first study to assess the effects of paraben exposure on couple fecundity in Asians. Given the widespread exposure to parabens in couples of childbearing age, the present findings may have important public health implications.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported in part by the National Natural Science Foundation of China (41991314), the Shanghai Science and Technology Development Foundation (22YF1426700), the Science and Technology Commission of Shanghai Municipality (21410713500), and the Shanghai Municipal Health Commission (2020CXJQ01). All authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Confounding by Indication in Studies of Selective Serotonin Reuptake Inhibitors

Selective serotonin reuptake inhibitors (SSRIs) are used worldwide as the first-line pharmacological treatment for depression. Although SSRI use can increase the risk of suicide, fractures, and infertility, the nature of these relationships is controversial. This review reports confounding by indication and confounding by severity for SSRI side effects in previously published observational studies. The PubMed and Google Scholar databases were searched for English-language articles published from 2005 to 2022. SSRIs are often prescribed for depressive symptoms, and depression is associated with an increased risk of side effects. Therefore, confounding by indication, whereby patients are selected for a particular treatment depending on their diagnosis or severity of illness, may lead to erroneous treatment conclusions, resulting in an adverse outcome. The side effects of SSRIs that can be considered due to confounding by indication or severity include suicide, fractures, infertility, atrial fibrillation, stroke, autism spectrum disorder, and congenital malformation. When prescribing SSRIs for depression, physicians must consider confounding by indication and severity in the management of side effects. In addition, medication discontinuation should be carefully considered when side effects occur during the treatment.

Obesity: A Doorway to a Molecular Path Leading to Infertility

The dramatic rise in obesity has recently made it a global health issue. About 1.9 billion were overweight, and 650 million global populations were obese in 2016. Obese women suffer longer conception time, lowered fertility rates, and greater rates of miscarriage. Obesity alters hormones such as adiponectin and leptin, affecting all levels within the hypothalamic-pituitary-gonadal axis. Advanced glycation end products (AGEs) and monocyte chemotactic protein-1 (MCP-1) are inflammatory cytokines that may play an important role in the pathophysiology of ovarian dysfunction in obesity. In obese males, there are altered sperm parameters, reduced testosterone, increased estradiol, hypogonadism, and epigenetic modifications transmitted to offspring. The focus of this article is on the possible adverse effects on reproductive health resulting from obesity and sheds light on different molecular pathways linking obesity with infertility in both female and male subjects. Electronic databases such as Google Scholar, Embase, Science Direct, PubMed, and Google Search Engine were utilized to find obesity and infertility-related papers. The search strategy is detailed in the method section. Even though multiple research work has shown that obesity impacts fertility in both male and female negatively, it is significant to perform extensive research on the molecular mechanisms that link obesity to infertility. This is to find therapeutics that may be developed aiming at these mechanisms to manage and prevent the negative effects of obesity on the reproductive system.

Androgen Receptor Gene CAG Repeat Length Varies and Affects Semen Quality in an Ethnic-Specific Fashion in Young Men from Russia

Male infertility is a multi-factorial and multi-genetic disorder, and the prevalence of male infertility in the world is estimated at 5–35%. The search for the causes of male infertility allowed for identifying a number of genetic factors including a single X-linked gene of the androgen receptor (AR), and some of its alleles are assumed to negatively affect male fertility. Our aim was (1) to study the variability of the length of CAG repeats of the AR gene and possible associations in the AR CAG genetic variants with semen quality and reproductive hormone levels in a population-based cohort of men and (2) to estimate distributions of AR CAG repeat alleles and associations with semen parameters in different ethnic subgroups. The cohort of 1324 young male volunteers of different ethnicities (median age 23.0 years) was recruited from the general population of five cities of the Russian Federation, regardless of their fertility status. Semen quality (sperm concentration, motility and morphology), reproductive hormone levels (testosterone, estradiol, LH, FSH and inhibin B) and trinucleotide (CAG) n repeat polymorphism in exon 1 of the AR gene were evaluated. The semen samples were analyzed according to the WHO laboratory manual (WHO, 2010), serum hormones were measured by enzyme immunoassay, and the AR CAG repeat length was analyzed by direct sequencing of leukocyte DNA. The median AR CAG repeat length in men of our multi-ethnic population was 23 (range 6–39). In the entire study population, a significant difference (p ≤ 0.05) was found in the frequency distribution and the mean values for the CAG repeat length between the groups with normal (23.2 ± 3.3) and impaired semen quality (23.9 ± 3.2). Additionally, we demonstrated that the total sperm count, sperm concentration, progressive motility and normal morphology were lower in the category of long CAG repeats (CAG ≥ 25) compared with those in the category of short CAG repeats (CAG ≤ 19); however, hormonal parameters did not differ between the long and short CAG categories, with the exception of estradiol. Significant differences were observed in the AR CAG repeat length between the most common ethnic cohorts of Slavs (Caucasians), Buryats (Asians), and Yakuts (Asians). The Buryats and Yakuts had a higher number of CAG repeats than the Slavs (medians: Slavs—23; Buryats—24; Yakuts—25). The range of alleles differed among ethnicities, with the Slavs having the largest range (7–36 repeats, 24 alleles total), the Yakuts having the smallest range (18–32 repeats, 14 alleles total) and the Buryats having the middle range (11–39 repeats, 20 alleles total). The longer CAG repeats were associated with an impaired semen quality within the Slavic (CAG ≥ 25) and Buryat (CAG ≥ 28) groups, but this effect was not found in Yakuts. Hormonal parameters did not differ between the three CAG repeat categories in men of all ethnic groups. This is the largest Russian study of the distribution of AR CAG repeats and the search for association between length of AR CAG repeat tract and impaired spermatogenesis in men from the general population. Our results confirmed the association of longer CAG repeats with a risk of impaired semen quality, but this association can be modified by ethnic origin. Identification of the number of AR CAG repeats can be an effective tool to assess the risk of male subfertility and the control of androgen hormone therapy of reproductive diseases.

Health Related Behaviors and Life Satisfaction in Patients Undergoing Infertility Treatment

The aim of the study was to evaluate the level of life satisfaction and health behaviors presented by patients with diagnosed infertility. This cross-sectional study included 456 patients (235 women and 221 men) from infertile couples in southeastern Poland from June 2019 to February 2020. Participants completed a questionnaire on sociodemographic characteristics, the Health Behaviors Inventory (HBI), and the Satisfaction with Life Scale (SWLS). The average score of severity of health behaviors for the study group was 82.96 points. Satisfaction with life at a higher level was declared by 57.6% of respondents, at an average level was declared by 31.4%, and at a lower level was declared by 11%. The SWLS score for the entire study group was 24.11 points (6.82 points on the sten scale). Respondents who achieved a higher rate of life satisfaction also had a higher level of severity of health behaviors (p < 0.0001). There were no significant differences between male and female SWLS scores, although the women had significantly higher rates of severity of health behaviors than men. The level of health behavior is positively related to life satisfaction in infertile patients. Medical personnel should conduct health education on a healthy lifestyle that promotes the improvement of reproductive health.

Natural self-emulsifying reversible hybrid-hydrogel delivery (N'SERH) of tocopherol enhances bioavailability and modulates alcohol-induced reproductive toxicity in rats

Alpha-tocopherol (α-Toc), an antioxidant vitamin, has been widely prescribing in the treatment of infertility, in spite of its limited oral bioavailability. The present study describes the enhanced bioavailability and efficacy of a novel 'natural self-emulsifying reversible hydrogel' (N'SERH)-based oral delivery form of α-Toc-rich sunflower oil (Tα-fen) using fenugreek galactomannan hydrogel scaffold (hybrid-FENUMATTM ). Tα-fen was characterised by FTIR, SEM, TEM and DLS as a hybrid-hydrogel powder. The bioavailability study on thirty (n = 30) male Sprague Dawley rats randomised into two groups indicated 4.84-fold increase in the oral bioavailability when the formulation was provided at 15 mg/kg b. wt. of α-Toc by oral gavage. The efficacy study on 24 animals randomised into four groups as control, ethanol treated (4 mg/kg b. wt.), ethanol+unformulated, UTα (15 mg/kg b. wt.) and ethanol+formulation, Tα-fen (15 mg/kg b. wt.) revealed significant improvement (*p < 0.05) and reversal of alcohol-induced reproductive toxicity as evident from the enhanced sperm count, motility and viability parameters, testosterone levels, fructose content, and SDH activity and plasma antioxidant status among Tα-fen-treated rats, compared with unformulated, UTα-treated group. Histopathology further confirmed the reversal of the alterations in the testes morphology of Tα-fen-treated animals, indicating its promising potential in the treatment of reproductive health issues.

Toxic Metal Concentrations in Drinking Water and Possible Effect on Sex Hormones among Men in Sabongida-Ora, Edo State, Nigeria

Drinking water can be a potential source of toxic metals, which are a known leading cause of infertility in men. This study determines the concentrations of lead (Pb), cadmium (Cd), zinc (Zn), copper (Cu) in drinking water (borehole, hand-dug well and treated water) and sex hormone levels (serum follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PROL), estradiol (E2), progesterone (PROG), and testosterone (T) in males who drink water mainly from these sources. The concentrations of Cd, and Pb in hand-dug wells were higher than the permissible limit recommended by the World Health Organization (WHO) while Zn and Cu were within the permissible levels in drinking water. Blood Cd and Pb levels were significantly higher (p < 0.001) among subjects who consumed hand-dug and borehole water than treated water, while serum Zn was significantly lower (p < 0.001) in hand-dug well and borehole water consumers than in control subjects. Also, serum FSH (p < 0.001), LH (p < 0.001), E2 (p < 0.002), PROG (p < 0.04) and T (p < 0.001) were significantly lower among hand-dug well and borehole water consumers than controls, while PROL (p < 0.001) was significantly higher in hand-dug well and borehole water consumers than controls. Blood Cd and Pb levels were significantly higher (p < 0.001) in hand-dug well water consumers than borehole water consumers. The consumption of water from hand-dug wells may have adverse reproductive sequelae among consumers.