Since its discovery, much attention has been drawn to irisin’s potential role in metabolic and reproductive diseases. This narrative review summarizes and updates the possible role played by this fascinating molecule in different physiological (puberty and menopause) and pathological (polycystic ovary syndrome (PCOS), functional hypothalamic amenorrhea (FHA), endometriosis, and gestational diabetes) conditions that can affect women throughout their entire lives. Irisin appears to be an important factor for the hypothalamic–pituitary–gonadal axis activation, and appears to play a role in the timing of puberty onset. Serum irisin levels have been proposed as a biomarker for predicting the future development of gestational diabetes (GDM). Its role in PCOS is still controversial, although an “irisin resistance” mechanism has been hypothesized. In addition to its impact on metabolism, irisin also appears to influence bone health. Irisin levels are inversely correlated with the prevalence of fractures in postmenopausal women. Similar mechanisms have also been postulated in young women with FHA. In clinical settings, further controlled, prospective and randomized clinical trials are needed to investigate the casual relationship between irisin levels and the conditions described and, in turn, to establish the role of irisin as a prognostic/diagnostic biomarker or a therapeutic target.

Background: Previous studies supported the beneficial effects of a very short abstinence period on sperm quality. This systematic review and meta-analysis aimed to evaluate the effects of a very short abstinence period (within 4 h) on assisted reproductive technique (ART) outcomes. Methods: A literature search was performed using the Pubmed, Scopus, Web of Science, and Cochrane databases. A meta-analysis was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) for randomized controlled trials (RCTs). All eligible studies were selected following the PICOS (Population, Intervention, Comparison/Comparator, Outcomes, Study type) model. The following pregnancy outcomes after ART were considered: fertilization rate (FR), implantation rate (IR), clinical pregnancy rate (CPR), live birth rate (LBR), and miscarriage rate (MR). This study was registered on PROSPERO (CRD42023396429). Results: We evaluated 414 records for eligibility, and 7 studies were ultimately included. Our analysis showed that a very short abstinence period significantly increased the IR, CPR, and LBR after ART. No significant differences were found for the FR and MR. Conclusions: A second ejaculation collected very shortly after the first one could represent a simple strategy to improve the results of ART, especially in couples including patients with abnormal sperm parameters.

Introduction: Female sexual dysfunctions (FSDs) have received little attention in the context of thyroid diseases, despite the high prevalence of both conditions. Objectives: This review aims to update and summarize the state of knowledge on the association between thyroid diseases and FSDs and to investigate the complex mechanisms through which thyroid hormone imbalance can impact female sexual health in the context of the biopsychosocial model. Methods: A comprehensive literature search was performed through the PubMed, MEDLINE, and Scopus databases, using the following keywords: “female sexual function,” “sexual dysfunction,” “hypoactive sexual desire disorder,” “thyroid disease,” “thyroiditis,” “hypothyroidism,” and “hyperthyroidism.” Results: To date, well-designed studies that describe the relationship between FSDs and thyroid disorders are lacking. However, despite the limitations on available studies, current data indicate that sexual alterations are frequently associated with thyroid diseases in women. A complex interplay of direct and indirect hormonal and nonhormonal mechanisms has been hypothesized, including hormonal changes, neurotransmitter imbalance, reduced nitric oxide release, mood disorders, and other systemic consequences of both hypothyroidism and hyperthyroidism. Thyroid hormone receptors have also been identified in the genitourinary system. Conclusions: In a clinical setting, physicians should investigate the sexuality of patients consulting for thyroid disease. At the same time, an evaluation of thyroid function should be performed in patients presenting with FSD, especially after menopause, when the risk of thyroid diseases and FSDs increases strongly.

Introduction: Psychological vulnerability is a relevant component of polycystic ovarian syndrome (PCOS), but it is still under-explored, especially during adolescence. The aim of this study was to describe a selection of psychometric characteristics in a clinical sample of Italian adolescents with PCOS. Moreover, we reported the associations of body image, eating attitudes, and mood with metabolic features. Methods: Our sample included 128 adolescent girls (age range: 14–19 years) with PCOS. Validated psychometric questionnaires were administered: State Anxiety Inventory (STAI), Beck Depression Inventory (BDI), Body Attitude Test (BAT), Bulimia Investigation Test (BITE), Eating Attitudes Test (EAT), and Perceived Stress Scale (PSS). Results: Anxiety was the most prevalent mood disorder (63.1% trait anxiety and 57% state anxiety). Our cohort also showed a high prevalence of depression (39.1%), body image dissatisfaction (49.2%), disordered eating (11.7%), and bulimic risk (41.4%). PCOS adolescents with obesity and insulin resistance (IR) had statistically significant higher body image distress compared to those with normal weight and without IR (p < 0.001). The Sobel test for mediation showed that body image dissatisfaction mediates the relationship between state anxiety and bulimic risk (Z = 3.42, p < 0.001) and between depression and bulimic risk (Z = 4.59, p < 0.001). Conclusions: A considerable number of patients with PCOS experience psychological disorders during adolescence. IR and obesity play a role in the distress associated with body image, further contributing to psychological vulnerability, especially in the bulimic domain. A comprehensive biopsychosocial approach in adolescents with PCOS represents the basis for effectively managing and preventing complications arising from both psychological and biological disorders in adulthood.

Background: The Small Nuclear Ribonucleoprotein Polypeptide N (SNRPN) gene is a paternally expressed imprinted gene, whose abnormal methylation appears to be associated with syndromes associated with the use of assisted reproductive techniques (ART), such as Angelman and Prader–Willi. Data present in the literature suggest the association between aberrant sperm SNRPN gene methylation and abnormal sperm parameters. The latest meta-analysis on the methylation pattern of this gene in spermatozoa of infertile patients published in 2017 reported a higher degree of methylation in the spermatozoa of infertile patients compared to fertile controls. Objectives: Here we provide an updated and comprehensive systematic review and meta-analysis of the sperm methylation pattern of the SNRPN gene in patients with abnormal sperm parameters/infertility compared to men with normal sperm parameters/fertile. For the first time in the literature, we performed a meta-regression analysis to evaluate whether age or sperm concentration could influence the methylation status of this gene at the sperm level. Methods: This meta-analysis was registered in PROSPERO (n. CRD42023397056). The Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) and the MOOSE guidelines for meta-analyses and systematic reviews of observational studies were strictly followed in our meta-analysis. According to our Population Exposure Comparison Outcome (PECO) question, we included data from original articles assessing the levels of SNRPN gene methylation at the sperm level in infertile patients or patients with abnormalities in one or more sperm parameters compared to fertile or normozoospermic men. Results: Only six of 354 screened studies were included in the quantitative synthesis. Our analysis showed significantly higher levels of SNRPN gene methylation in patients compared to controls. However, significant heterogeneity was found between studies. In sensitivity analysis, no studies were sensitive enough to skew the results. The Egger test showed no publication bias. In the meta-regression analysis, the results were independent of age and sperm concentration in the overall population. The same results were found in the control group. However, when analyzing the patient group, a direct correlation was found between SNRPN methylation and age, indicating that the degree of methylation of the SNRPN gene increases with advancing age. Conclusions: Fertility status or abnormality of sperm parameters is associated with a change in the methylation pattern of the SNRPN gene, with higher levels found in infertile patients or those with abnormal sperm parameters compared to fertile men or men with normal sperm parameters. In the group of infertile patients/patients with abnormal sperm parameters, age was directly correlated to the degree of SNRPN methylation, highlighting the presence of a mechanism that explains the age-related altered sperm quality and the risk of ART. Despite some limitations present in the analyzed studies, our results support the inclusion of SNRPN methylation in the genetic panel of prospective studies aimed at identifying the most representative and cost-effective genes to analyze in couples who want to undergo ART.

Sommario: La menopausa rappresenta una fase cruciale di transizione cardiometabolica durante la quale molte donne sperimentano un incremento ponderale e una significativa redistribuzione del grasso corporeo. Parallelamente, si osserva spesso un declino della funzione sessuale. Le donne affette da obesità sono esposte a una molteplicità di fattori di rischio, sia organici che psicosociali, che le predispongono maggiormente allo sviluppo di disfunzioni sessuali. La presente rassegna si propone di analizzare le evidenze scientifiche disponibili sulla correlazione tra obesità e disfunzioni sessuali nelle donne in menopausa e di fornire strumenti utili per agevolare il dialogo medico-paziente, diagnosticare le disfunzioni sessuali e offrire opzioni terapeutiche seguendo un modello bio-psico-sociale.