The combined therapy myo-inositol plus d-chiro-inositol, rather than d-chiro-inositol, is able to improve IVF outcomes: results from a randomized controlled trial

D-chiro-inositol effectively counteracts endometriosis in a mouse model

BACKGROUND

Endometriosis, a common condition affecting 5-10% of women of reproductive age, is the growth of endometrial-like tissue outside the uterus, leading to pain and infertility. Current treatments, such as surgery and hormonal therapy, offer limited long-term benefits. This study investigated the potential of D-chiro inositol (DCI), a natural compound that influences ovarian steroidogenesis, to treat endometriosis and compared its efficacy with a progestin drug such as Dienogest (DG).

METHODS

We established a non-surgical mouse model of endometriosis in CD1 mice. Uterine horns were removed from donor mice, cut into fragments and inoculated in recipient mice by intraperitoneal injection. Endometriosis progression was assessed at 15, 21 and 28 days after transplantation, with the 28-day window being the most effective. The mice were then randomly assigned to four experimental groups, which received for 28 days: water (EMS); DCI 0.4 mg/die (DCI); DCI 0.2 mg/die and Dienogest 0.33 ng/die (DCI + DG); DG 0.67 ng/die (DG). At the end of the treatments, endometriotic lesions, ovaries and circulating estradiol levels were analyzed.

RESULTS

The results showed that treatment with DCI, both alone and in combination with DG, significantly reduced the number, size and vascularization of endometriotic lesions compared to the EMS control group. Histological analysis confirmed a decrease in endometriotic foci across all treatment groups, with the most pronounced effects in the DCI group. To investigate the underlying molecular mechanisms, we found that DCI led to a significant reduction in the expression of Sirt1 and an increase in E-Cadherin, indicating a reduction in EMT transition relevant for lesion development. In addition, DCI decreased cell proliferation and,blood vessel formation, as evaluated by PCNA and CD34, respectively. Futhermore, in the ovary, DCI treatment downregulated the expression of aromatase (Cyp19a1), the enzyme critical for estrogen biosynthesis, and increased the number of primordial to antral follicles, suggesting a beneficial effect on ovarian folliculogenesis.

CONCLUSIONS

By modulating proliferation, EMT transition and aromatase activity, DCI emerges as a promising compound for endometriosis treatment.

Diacerein and myo-inositol alleviate letrozole-induced PCOS via modulation of HMGB1, SIRT1, and NF-kB: A comparative study

Polycystic ovary syndrome (PCOS) is the most prevalent cause of anovulatory infertility in women. Myo-inositol supplementation has displayed effectiveness in curing PCOS patients. Diacerein, an anti-inflammatory medication, has not been extensively studied in the context of reproductive disorders. This study aimed to compare the role of myo-inositol and diacerein in PCOS and the probable mechanisms mediating their actions. Forty adult female rats were divided equally into the following: control, PCOS, PCOS+Myo-inositol, and PCOS+Diacerein groups. Rats were subjected to arterial blood pressure (ABP), electromyography (EMG), and uterine reactivity measurements. Blood samples were collected for measuring hormonal assays, glycemic state, lipid profile, oxidative stress, and inflammatory markers. Ovaries and uteri were extracted for histological examination, including hematoxylin and eosin staining, Masson's trichrome staining, immunohistochemistry, and rt-PCR analysis of ovarian tissues. PCOS was associated with significant increases in ABP, uterine frequency and amplitude of contraction, luteinizing hormone, testosterone, lipid, glycemic and inflammatory markers, malondialdehyde, high-mobility group box 1 (HMGB1), nuclear factor kappa (NF-kB), ovarian fibrosis, and endometrial thickening. In contrast, there was a significant reduction in follicular stimulating hormone, reduced glutathione, and Sirtuin 1 (SIRT1) when compared with control group. Both myo-inositol and diacerein counteract PCOS changes; but diacerein's effects were superior to myo-inositol's for all parameters, except for lipid and glycemic markers. Diacerein possessed anti-inflammatory properties and showed significant efficacy in mitigating the endocrinal, metabolic, and ovarian structural alterations linked to PCOS. Its beneficial actions likely stem from reducing oxidative stress, dyslipidemia, and hyperglycemia, potentially through the modulation of HMGB1, SIRT1, and NF-kB pathways.

Effect of myo-inositol supplementation in mixed ovarian response IVF cohort: a systematic review and meta-analysis

Objective

There has been substantial research conducted recently on the effect of myo-inositol (MI) on human reproduction. However, it still remains ambiguous about the therapeutic efficacy of MI in infertile women undergoing in vitro fertilization embryo transfer (IVF-ET). This systematic review and meta-analysis was carried out to investigate the efficacy of MI on IVF outcomes.

Methods

Literatures were searched in the PubMed, Web of Science, Cochrane Library, ScienceDirect and Wanfang databases. The methodological quality was assessed using the Cochrane Risk of Bias tool. Data were pooled using a random- or fixed-effects model according to study heterogeneity. The results are expressed as odds ratio (OR) or mean difference (MD) with 95% confidence intervals (CIs). Heterogeneity was measured by the I2 statistic. The protocol was prospectively registered with PROSPERO (CRD42024582149).

Results

Eleven eligible studies with 981 participants reported the IVF outcomes of the MI group versus the control group. The synthesis results showed that the metaphase II (MII) oocyte rate was higher in the MI group than in the control group (OR 1.55, 95% CI 1.04-2.31, P=0.03). For polycystic ovary syndrome (PCOS) women, as well as non-obese PCOS women, a statistically significant improvement in MII oocyte rate were assumed after taking MI (OR 1.97, 95% CI 1.20-3.25, P<0.01; OR 1.92, 95% CI 1.09-3.37, P=0.02) while there is no statistically significant advancement showed in the poor ovary responder (POR) women(OR 0.97, 95% CI 0.35-2.68, P=0.95). The fertilization rate was higher in the MI group than in the control group (OR 1.62, 95% CI 1.21-2.16, P<0.01), for PCOS, non-obese PCOS and POR women (OR 1.59, 95% CI 1.16-2.18, P<0.01; OR 1.87, 95% CI 1.52-2.31, P<0.01; OR 2.42, 95% CI 1.48-3.95, P<0.01).

Conclusions

Our results suggest that MI supplementation improves the MII oocyte rate and the fertilization rate. More high-grade evidence from prospective randomized studies is warranted.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42024582149.

The Clinical Use of Myo-Inositol in IVF-ET: A Position Statement from the Experts Group on Inositol in Basic and Clinical Research and on PCOS (EGOI-PCOS), the Polish Society of Andrology, and the International Scientific Association for the Support and Development of Medical Technologies

Background: Myo-inositol plays a vital role in human health, functioning as a second messenger of FSH and facilitating the transport of glucose into the cell. Consequently, myo-inositol is regularly utilized in the treatment of polycystic ovary syndrome (PCOS), wherein it acts upon metabolic factors, improving insulin sensitivity and reducing total androgen levels. Patients with PCOS frequently suffer from infertility; thus, the use of myo-inositol has been explored in improving assistive reproductive technique (ART) procedures. This is by no means limited to patients with PCOS, as inositol has found applications in non-PCOS patient groups in addition to in male factor infertility. This joint statement from the Experts Group on Inositol in Basic and Clinical Research and on PCOS (EGOI-PCOS), the Polish Society of Andrology, and the International Scientific Association for the Support and Development of Medical Technologies discusses the latest evidence on this topic, with the aim of interrogating whether myo-inositol could be implemented in everyday ART patient care. Methods: The authors conducted a narrative review performed via an independent literature search between July and August 2024, using the search platforms PubMed, Web of Science, and Google Scholar. Results: In both non-PCOS and PCOS populations seeking IVF care, MI supplementation prior to ovarian stimulation may positively affect gonadotropin use and duration, oocyte and embryo quality, fertilization, and clinical pregnancy rates. Conclusions: This position statement recommends that myo-inositol be considered as a potential pretreatment strategy prior to ovarian hyperstimulation with gonadotropins.

Improvement in biochemical manifestations of the serum and follicular fluid and ICSI outcomes in PCOS patients with myo-inositol administration: prospective randomized research

The research investigated the capacity of myo-inositol (MI) in order that it improves biochemical markers in serum and follicular fluid and, ultimately, intracytoplasmic sperm injection (ICSI) outcomes of women with PCOS. Sixty infertile patients with PCOS, who were undergoing ovulation induction for ICSI, were randomly divided to two groups. The MI group received 2000 mg myo-inositol + 1 mg folic acid twice a day for 6 weeks with starting the ICSI cycle. For the same period, the control group received a placebo containing only folic acid (1 mg). Levels of hormonal profiles in serum and follicular fluid, as well as oxidative stress markers (MDA, TAC, GPx, and SOD), were estimated using an ELISA assay. Primary end points were ICSI cycle outcomes. Compared to the placebo group, the MI group demonstrated significant reduction in serum and follicular fluid levels of LH, LH/FSH ratio, total testosterone, AMH, and androstenedione. Furthermore, the MI group exhibited meaningful increases in TAC, GPx, and SOD, but MDA significantly decreased. While the number of retrieved and mature oocytes is not statistically similar among the groups, the MI group showed significant improvements in the percentage of immature oocytes, cleavage rate, and good embryo quality. A meaningful correlation was checked between follicular fluid AMH level and LH, FSH, total testosterone, androstenedione, insulin, MDA, the number of retrieved oocytes, and immature oocytes. Our outcomes indicate that myo-inositol administration in women with PCOS undergoing ART helps to improve their hormonal profiles, and the quality of oocytes and embryos. Registration details: Date: 2022.10.19, Registry: https://irct.behdasht.gov.ir/trial/66005 , and Trial registration: IRCT202220921056008N1.

Myo-Inositol and Its Derivatives: Their Roles in the Challenges of Infertility

Myo-inositol (MYO) and D-chiro-inositol (DCI) are the two most significant isomeric forms of inositol, playing a critical role in intracellular signaling. MYO is the most abundant form of inositol in nature; DCI is produced from MYO through epimerization by an insulin-dependent enzyme. Recently, it has been demonstrated that inositol may influence oocyte maturation and improve intracellular Ca2+ oscillation in the oocytes, and it has been proposed as a potential intervention for restoring spontaneous ovulation. The MYO concentration in human follicular fluid is considered a bioindicator of oocyte quality. In the ovary, DCI modulates the activity of aromatase, thus regulating androgen synthesis. Under physiological conditions, the MYO/DCI ratio is maintained at 40:1 in plasma. In women with PCOS, the MYO/DCI ratio is lowered to 0:2:1, contributing to elevated androgen production. By regulating FSH signaling, MYO administration increases the number of high-quality embryos available for transfer in poor responder patients. Finally, by acting downstream to insulin signaling, inositol administration during pregnancy may represent a novel strategy for counteracting gestational diabetes. These findings show that diet supplementation with inositol may be a promising strategy to address female infertility and sustain a healthy pregnancy.

Effectiveness of Myo-Inositol on Oocyte and Embryo Quality in Assisted Reproduction: Systematic Review and Meta-Analysis of Randomized Clinical Trials

INTRODUCTION

We sought to conduct a systematic review and meta-analysis of randomized clinical trials (RCTs) to evaluate the impact of myo-inositol on oocyte and embryo quality in women undergoing assisted reproduction.

METHODS

The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 checklist (registration number: CRD42023433328). Studies were identified by searching PubMed, Cochrane Library, Google Scholar, Scopus, Embase, and ClinicalTrials databases.

RESULTS

Eight RCTs were included for qualitative analysis reporting on 820 participants. Four meta-analyses were performed. Numbers of retrieved oocytes in comparison of intervention and control group were higher in inositol group (mean difference [MD] = 0.41, 95% CI: 0.05-0.77, p = 0.02). Meta-analysis of two studies comparing numbers of oocytes among poor ovarian responder patients showed no significant difference between intervention and control group (MD = 0.50, 95% CI: 0.57-1.58, p = 0.36). Miscarriage rate has no statistically significant difference between the treatment and control groups (risk ratios [RRs] = 0.81, 95% CI: 0.20-3.32, p = 0.77). Inositol played no role in improving clinical pregnancy rates; there was no significant difference between the intervention group and the control group (RR = 1.41, 95% CI: 0.88-2.25, p = 0.15).

CONCLUSION

Thus, we did not find any benefits of using myo-inositol on oocyte and embryo quality in women undergoing reproductive technologies. Further studies are needed to assess efficacy, safety, and high compliance by female patients.

Treatment With a Patented 3.6:1 Myo-Inositol to D-chiro-Inositol Ratio, Antioxidants, Vitamins and Minerals Food Supplement in Women With a History of Assisted Reproductive Technique (ART) Failures: A Series of Case Reports

Infertility affects 15% of couples in reproductive age worldwide. In women in particular, infertility can be caused by various abnormalities, with polycystic ovary syndrome (PCOS) being the most common. Currently, there are many assisted reproductive techniques (ART) available to combat the burden of infertility. However, positive results are not guaranteed. The administration of inositol has been shown to increase positive reproductive outcomes in women undergoing ART. Here we present a series of clinical cases in which women with a history of infertility and previously failed ART, supplemented with a specific 3.6:1 MYO:DCI ratio, antioxidants, vitamins, and minerals for a period of 1 to 3 months before undergoing in vitro fertilization (IVF). In this series of case reports, we provide preliminary evidence that supplementation with a specific 3.6:1 MYO to DCI ratio, as well as antioxidants, vitamins, and minerals may contribute positively to female fertility in women undergoing IVF, with a history of primary or secondary infertility and previously failed ART.

The role of myo-inositol supplement in assisted reproductive techniques

Assisted reproductive techniques can help many infertile couples conceive. Therefore, there is a need for an effective method to overcome the widespread problems of infertile men and women. Oocyte and sperm quality can increase the chances of successful in vitro fertilisation. The maturation environment in which gametes are present can affect their competency for fertilisation. It is well established that myo-inositol (MI) plays a pivotal role in reproductive physiology. It participates in cell membrane formation, lipid synthesis, cell proliferation, cardiac regulation, metabolic alterations, and fertility. This molecule also acts as a direct messenger of insulin and improves glucose uptake in various reproductive tissues. Evidence suggests that MI regulates events such as gamete maturation, fertilisation, and embryo growth through intracellular Ca2 + release and various signalling pathways. In addition to the in-vivo production of MI from glucose in the reproductive organs, its synthesis by in vitro-cultured sperm and follicles has also been reported. Therefore, MI is suggested as a therapeutic approach to maintain sperm and oocyte health in men and women with reproductive disorders and individuals of reproductive age.

Advances in non-hormonal pharmacotherapy for the treatment of male infertility: the role of inositols

INTRODUCTION

Several antioxidants are available for the treatment of male infertility. Although the benefit of myo-inositol (MYO) and D-chiro-inositol (DCI) for female infertility is recognized, their role in male infertility is a matter of debate.

AREAS COVERED

The authors review the impact that treatment with MYO and/or DCI may have on conventional and bio-functional sperm parameters [mitochondrial membrane potential (MMP), sperm chromatin compactness, and sperm DNA fragmentation (SDF)], seminal oxidative stress (OS) and pregnancy, miscarriage, and live birth rates, and the possible mechanisms involved. Furthermore, the authors gather evidence on the effects of MYO and/or DCI on sperm function in vitro.

EXPERT OPINION

MYO can improve sperm count, motility, capacitation, acrosome reaction, and MMP. No data are currently available on the effects of DCI in vivo. Both MYO and DCI ameliorate sperm motility and MMP in vitro. Therefore, the use of inositols should be preferred in patients with idiopathic asthenozoospermia, especially in case of impaired sperm mitochondrial function. Due to their insulin-sensitizing action, a role for these molecules may be envisaged for the treatment of infertility caused by carbohydrate metabolism derangement.

D-chiro-inositol Induces Ovulation in Non-Polycystic Ovary Syndrome (PCOS), Non-Insulin-Resistant Young Women, Likely by Modulating Aromatase Expression: A Report of 2 Cases

Case series

Patients: Female, 19-year-old • Female, 23-year-old

Final Diagnosis: Anovulation

Symptoms: Oligomenorrhea

Medication: —

Clinical Procedure: —

Specialty: Obstetrics and Gynecology

Fundamental Concepts and Novel Aspects of Polycystic Ovarian Syndrome: Expert Consensus Resolutions

Polycystic ovary syndrome (PCOS) is a very common endocrine and metabolic disorder with the involvement of both genetic and environmental factors. Although much has been clarified on its pathogenesis, diagnosis, clinical manifestations, and therapy, there are still areas of uncertainty. To address fundamental concepts, novel aspects and hypotheses, and future perspectives, including the possible additional benefits of treatment with nutraceuticals, an expert consensus panel formed by endocrinologists and gynecologists was established. After an independent review of the literature, the panel convened electronically on February 3, 2020, and six resolutions were created, debated, and agreed upon discussion, and finally approved in their final form in a consensus livestream meeting held on April 15. The summary of the resolutions are: (1) PCOS is a well-established medical condition that negatively affects reproduction, general health, sexual health, and quality of life; (2) the symptoms and signs of PCOS appear early in life especially in female newborns from PCOS carriers; (3) women with PCOS have significantly increased risk of pregnancy-related complications including gestational diabetes mellitus; (4) a male PCOS equivalent exists, and it may impact on metabolic health and probably on reproduction; (5) the evidence supports that medical therapy for PCOS is effective, rational, and evidence-based; (6) the evidence supports a major research initiative to explore possible benefits of nutraceutical therapy for PCOS. The proposed resolutions may be regarded as points of agreement based on the current scientific evidence available.

High Doses of D-Chiro-Inositol Alone Induce a PCO-Like Syndrome and Other Alterations in Mouse Ovaries

Administration of 1000-1500 mg/day D-Chiro-Inositol (DCIns) or a combination of Myo-Inositol (MyoIns) and DCIns in their plasma molar ratio (40:1) for three or more months are among recommended treatments for metabolic syndrome and/or Polycystic Ovary Syndrome (PCOS). We previously confirmed the efficacy of this formulation (8.2 mg/day MyoIns and 0.2 mg/day DCIns for 10 days) in a mouse PCOS model, but also observed negative effects on ovarian histology and function of formulations containing 0.4-1.6 mg/day DCIns. We therefore analyzed effects of higher doses of DCIns, 5, 10 and 20 mg/day, administered to young adult female mice for 21 days, on ovarian histology, serum testosterone levels and expression of the ovarian enzyme aromatase. Five mg/day DCIns (human correspondence: 1200 mg/day) altered ovarian histology, increased serum testosterone levels and reduced the amount of aromatase of negative controls, suggesting the induction of an androgenic PCOS model. In contrast, 10-20 mg/day DCIns (human correspondence: 2400-4800 mg/day) produced ovarian lesions resembling those typical of aged mice, and reduced serum testosterone levels without affecting aromatase amounts, suggesting a failure in steroidogenic gonadal activity. Notwithstanding physiological/biochemical differences between mice and humans, the observed pictures of toxicity for ovarian histology and function recommend caution when administering DCIns to PCOS patients at high doses and/or for periods spanning several ovulatory cycles.

Myo-Inositol as a Key Supporter of Fertility and Physiological Gestation

Pregnancy is a complex process, featuring several necessary changes in women's physiology. Most women undergo healthy pregnancies; even so, several women experience reduced fertility or pathologies related to the pregnancy. In the last years, researchers investigated several molecules as promoters of fertility. Among all, myo-inositol (myo-ins) represents a safe compound that proved useful in issues related to fertility and pregnancy. In fact, myo-ins participates in several signaling processes, including the pathways of insulin and gonadotropins, and, therefore, it is likely to positively affect fertility. In particular, several clinical trials demonstrate that its administration can have therapeutic effects in infertile women, and that it can also be useful as a preventive treatment during pregnancy. Particularly, myo-ins could prevent the onset of neural tube defects and the occurrence of gestational diabetes mellitus, promoting a trouble-free gestation. Due to the safety and efficiency of myo-ins, such a treatment may also substitute several pharmaceuticals, which are contraindicated in pregnancy.

Natural Molecules in the Management of Polycystic Ovary Syndrome (PCOS): An Analytical Review

Polycystic ovary syndrome (PCOS) is a heterogenous disorder characterized by chronic ovulation dysfunction and hyperandrogenism. It is considered the most common endocrinological disorder, affecting up to 25% of women of reproductive age, and associated with long-term metabolic abnormalities predisposing to cardiovascular risk, such as insulin resistance (IR), dyslipidemia, endothelial dysfunction, and systemic inflammation. PCOS is also characterized by elevated serum levels of luteinizing hormone (LH), causing a condition of hyperandrogenism and a consequent altered ratio between LH and the follicle stimulating hormone (FSH). Over the years, several different approaches have been proposed to alleviate PCOS symptoms. Supplementation with natural molecules such as inositols, resveratrol, flavonoids and flavones, vitamin C, vitamin E and vitamin D, and omega-3 fatty acids may contribute to overcoming PCOS pathological features, including the presence of immature oocyte, IR, hyperandrogenism, oxidative stress and inflammation. This review provides a comprehensive overview of the current knowledge about the efficacy of natural molecule supplementation in the management of PCOS.

The effect of Myo-inositol on fertility rates in poor ovarian responder in women undergoing assisted reproductive technique: a randomized clinical trial

BACKGROUND

Poor ovarian response to gonadotropin is a significant challenge in assisted reproductive technique (ART) and affect 9-24% of ART cycles. This study aimed to evaluate the effect of Myo-inositol on fertility rates in poor ovarian responder women undergoing assisted reproductive technique.

METHODS

This study is a double-blinded randomized controlled study that involved 60 poor ovarian responders included in an ICSI program and divided into two groups; intervention group: 30 patients who have been assuming Inofolic (4 g myo-inositol + 400 μg folic acid) for the before the enrollment day; control group: 30 patients assuming folic acid (400 μg) for the same period. Controlled ovarian stimulation was performed in the same manner in the two groups. The main outcomeswere the assessment of oocytes retrievednumber and quality, ovarian sensitivity index,required dose of Gonadotropinsunits × 1000), fertilization rate, biochemical, and clinical pregnancy rate.

RESULT

There is no significant difference in clinical characteristics between study groups. The number of oocytes retrieved, number of MII oocytes, number of embryos transferred, chemical, and clinical pregnancy were higher in the intervention group. However, they are not statistically significant in comparison to the control group. The ovarian sensitivity index and fertilization rate were significantly higher in the intervention group than the control group (P > 0.05). The required dose of gonadotropin significantly lower in the intervention group than the control group.

CONCLUSION

Our results suggest that the supplementation myo-inositol in poor ovarian responders significantly improved the ART outcomes such as fertilization rate gonadotropin, ovarian sensitivity index (OSI) and significantly reduced the required unities of gonadotropin. Additionally, more extensive randomized controlled studies are needed.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials, IRCT20180515039668N1 , retrospectively registered since 2020-03-16.

Impact of myo-inositol treatment in women with polycystic ovary syndrome in assisted reproductive technologies

Polycystic ovary syndrome (PCOS) is marked in 30 to 40% by insulin resistance and hyperandrogenism. Myo-inositol (MI) increases insulin sensitivity, decreases hyperandrogenism and improves the menstrual cycle. Its effect during assisted reproductive technologies (ART) has been studied by many authors. We conducted a review of the literature on the impact of MI administration in PCOS women in assisted reproductive technologies. Myo-inositol is effective in normalizing ovarian function, improving oocyte and embryo quality in PCOS, however further evaluations by large multicentre randomized controlled trials are needed to assess the clinical pregnancy and live birth rates in ART.

A review of the role of inositols in conditions of insulin dysregulation and in uncomplicated and pathological pregnancy

Inositols, a group of 6-carbon polyols, are highly bioactive molecules derived from diet and endogenous synthesis. Inositols and their derivatives are involved in glucose and lipid metabolism and participate in insulin-signaling, with perturbations in inositol processing being associated with conditions involving insulin resistance, dysglycemia and dyslipidemia such as polycystic ovary syndrome and diabetes. Pregnancy is similarly characterized by substantial and complex changes in glycemic and lipidomic regulation as part of maternal adaptation and is also associated with physiological alterations in inositol processing. Disruptions in maternal adaptation are postulated to have a critical pathophysiological role in pregnancy complications such as gestational diabetes and pre-eclampsia. Inositol supplementation has shown promise as an intervention for the alleviation of symptoms in conditions of insulin resistance and for gestational diabetes prevention. However, the mechanisms behind these affects are not fully understood. In this review, we explore the role of inositols in conditions of insulin dysregulation and in pregnancy, and identify priority areas for research. We particularly examine the role and function of inositols within the maternal-placental-fetal axis in both uncomplicated and pathological pregnancies. We also discuss how inositols may mediate maternal-placental-fetal cross-talk, and regulate fetal growth and development, and suggest that inositols play a vital role in promoting healthy pregnancy.

Effect of d-chiro-inositol and alpha-lipoic acid combination on COH outcomes in overweight/obese PCOS women

Insulin resistance (IR) plays a central role in the onset of polycystic ovary syndrome (PCOS). Insulin so insulin-sensitizing like inositols have been proposed as first line therapy. Among them d-chiro-inositol (DCI) seems to improve glucose metabolism and to increase ovulation frequency. Other studies have demonstrated that alpha-lipoic acid (ALA), with its antioxidant role, can also improve endocrine and metabolic profile of PCOS patients especially with familial diabetes. This a retrospective observational study with the aim to evaluate possible advantages of an integrative preparation combining DCI 500 mg and ALA 300 mg in overweight/obese PCOS patients with or without diabetic relatives who underwent IVF. Twenty PCOS patients who were taking the integrative preparation underwent controlled ovarian hyperstimulation in our center. The group with diabetic relatives tended to have a lower dose of gonadotropin, shorter stimulation days, higher number of MII oocytes, and higher number of fertilized oocytes. A combined regimen of DCI and ALA could be an interesting strategy in overweight PCOS patients with familial diabetes underwent ART.

Fundamental Concepts and Novel Aspects of Polycystic Ovarian Syndrome: Expert Consensus Resolutions

Polycystic ovary syndrome (PCOS) is a very common endocrine and metabolic disorder with the involvement of both genetic and environmental factors. Although much has been clarified on its pathogenesis, diagnosis, clinical manifestations, and therapy, there are still areas of uncertainty. To address fundamental concepts, novel aspects and hypotheses, and future perspectives, including the possible additional benefits of treatment with nutraceuticals, an expert consensus panel formed by endocrinologists and gynecologists was established. After an independent review of the literature, the panel convened electronically on February 3, 2020, and six resolutions were created, debated, and agreed upon discussion, and finally approved in their final form in a consensus livestream meeting held on April 15. The summary of the resolutions are: (1) PCOS is a well-established medical condition that negatively affects reproduction, general health, sexual health, and quality of life; (2) the symptoms and signs of PCOS appear early in life especially in female newborns from PCOS carriers; (3) women with PCOS have significantly increased risk of pregnancy-related complications including gestational diabetes mellitus; (4) a male PCOS equivalent exists, and it may impact on metabolic health and probably on reproduction; (5) the evidence supports that medical therapy for PCOS is effective, rational, and evidence-based; (6) the evidence supports a major research initiative to explore possible benefits of nutraceutical therapy for PCOS. The proposed resolutions may be regarded as points of agreement based on the current scientific evidence available.

Inositols' Importance in the Improvement of the Endocrine-Metabolic Profile in PCOS

Polycystic ovary syndrome (PCOS) is one of the most common causes of infertility and metabolic problems among women of reproductive age. The mechanism of PCOS is associated with concurrent alterations at the hormonal level. The diagnosis assumes the occurrence of three interrelated symptoms of varying severity, namely ovulation disorders, androgen excess, or polycystic ovarian morphology (PCOM), which all require a proper therapeutic approach. The main symptom seems to be an increased androgen concentration, which in turn may contribute to different metabolic disorders. A number of papers have demonstrated the significant role of inositol therapy in PCOS. However, there is a lack of detailed discussion about the importance of myo-inositol (MI) and d-chiro-inositol (DCI) in reference to particular symptoms. Thus, the aim of this review is to present the effectiveness of MI and DCI treatment for PCOS symptoms. Moreover, the review is focused on analyzing the use of inositols, taking into account their physiological properties, together with the mechanism of individual PCOS symptom formation.

Comparison of the effect of two combinations of myo-inositol and D-chiro-inositol in women with polycystic ovary syndrome undergoing ICSI: a randomized controlled trial

The purpose of this study was to evaluate the effect of two doses of D-chiro-inositol (DCI) in combination with Myo-inositol (MYO) in women with PCOS undergoing ICSI. This was a multicenter controlled, randomized, double-blind parallel group study with two MYO-DCI formulations for 12 weeks. The study group (SG) was administered 550 mg of MYO + 150 mg of DCI twice daily; the control group (CG) was administered 550 mg of MYO + 13.8 mg of DCI twice daily. The participants comprised 60 women with PCOS undergoing ICSI. At baseline, no differences were found between the two groups regarding age, BMI, HOMA-IR or testosterone levels. The pregnancy and live birth rates were significantly higher in the SG than in the CG (65.5 vs. 25.9 and 55.2 vs. 14.8, respectively) [risk ratio (RR) = 0.4; 95%CI (0.2, 0.79); p = .003 and RR = 0.27; 95%CI (0.10, 0.70); p = .002 respectively]. The risk of ovarian hyperstimulation syndrome (OHSS) was lower in the SG (3.44 vs. 18.5%, p = .07). The combination of MYO-DCI at high doses of DCI improves the pregnancy rates and reduces the risk of OHSS in women with PCOS undergoing ICSI.

Efficacy of combination therapy of inositols, antioxidants and vitamins in obese and non-obese women with polycystic ovary syndrome: an observational study

Polycystic ovarian syndrome (PCOS) is one of the most common endocrine disorders in women of both developed and developing countries. It is associated with insulin resistance, hyperinsulinemia, hyperandrogenism, oxidative stress and various long-term complications. The present study was undertaken to evaluate the efficacy and safety of the supplementation (Trazer F Forte^TM-CORONA Remedies Pvt. Ltd.) providing combination of insulin sensitising agents (myo-inositol, D-chiro-inositol and chromium picolinate), antioxidants (N-acetylcysteine and lycopene) and vitamins (vitamin D, biotin and folic acid) in women with PCOS. After 12 weeks of supplementation, a significant improvement was observed in menstrual cyclicity, acne and hirsutism in both obese and lean PCOS patients. A significant reduction was observed in body weight and BMI of obese subjects. However, both parameters remain unchanged in lean subjects. We suggest that combination therapy of insulin sensitising agents, antioxidants and vitamins may be a fruitful approach for the management of PCOS.Impact statementWhat is already known on this subject? Monotherapy of insulin sensitising agents, antioxidants and vitamins is beneficial in the treatment of PCOS.What do the results of this study add? Combined use of insulin sensitising agents (myo-inositol, D-chiro-inositol and chromium picolinate), antioxidants (N-acetylcysteine and lycopene), and vitamins (vitamin D, biotin and folic acid) is safe and effective in obese and non-obese women with PCOS.What are the implications of these findings for clinical practice and/or further research? Since PCOS is a multifactorial and a complex endocrine disorder, combination therapy can be used for the comprehensive management of PCOS.

Myo-inositol and D-chiro-inositol (40:1) reverse histological and functional features of polycystic ovary syndrome in a mouse model

Mice exposed to continuous light undergo functional and histological changes that mimic those of human Polycystic Ovary Syndrome (PCOS). We herein induced the syndrome by exposing 30-day-old females to 10 weeks of permanent light. Ovarian morphology and histology, as well as reproductive parameters (time of observed pregnancy/delivery) were investigated. Ovaries of PCOS-modeled mice showed lack of tertiary follicles and corpora lutea, altered ovarian architecture, and increased thickness of the theca layer. When mice were returned to a normal light-dark regimen for 10 days, a slight, spontaneous improvement occurred, whereas a quick and almost complete recovery from PCOS signs and symptoms was obtained by treating animals with a daily supplementation of 420 mg/kg myo-inositol and D-chiro-inositol (MyoIns/DCIns) in a 40:1 molar ratio. Namely, ovaries from mice treated by this protocol recovered normal histological features and a proper ratio of theca/granulosa cell layer thickness (TGR), suggesting that the androgenic phenotype was efficiently reversed. Indeed, we identified TGR as a useful index of PCOS, as its increase in PCOS-modeled mice correlated linearly with reduced reproductive capability ( r = 0.75, p < 0.0001). Mice treated with a 40:1 formula regained low TGR values and faster recovery of their fertility, with a physiological delivery time after mating. On the other hand, a higher D-chiro-inositol treatment formula, such as MyoIns versus DCIns 5:1, was ineffective or even had a negative effect on clinical-pathological outcomes.

The effect of myo-inositol/di-chiro-inositol on markers of ovarian reserve in women with PCOS undergoing IVF/ICSI: A systematic review and meta-analysis

INTRODUCTION

High levels of anti-Mullerian hormone and a high antral follicle count in women with polycystic ovary syndrome, reflecting increased ovarian antral follicles, predisposes them to have a high number of retrieved oocytes with in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) and an increased risk of ovarian hyperstimulation syndrome. Inositols, which act as insulin sensitizers, have the potential to alter folliculogenesis and the functional ovarian reserve, with subsequent benefits to reproductive outcomes following IVF/ICSI treatment. Published literature is, however, unable to provide definitive evidence of its efficacy. The objective of our review was to evaluate the effect of inositols on anti-Mullerian hormone, antral follicle count and reproductive outcomes in women with polycystic ovary syndrome undergoing IVF/ICSI.

MATERIAL AND METHODS

We performed a literature search using standard methodology recommended by Cochrane. Randomized controlled trials and non-randomized studies comparing inositols with no treatment, placebo or other treatment were included in the review. Using standard methodology recommended by Cochrane we pooled results using the random effects model; our findings were reported as relative risk or mean differences. PROSPERO registration: CRD42017082275.

RESULTS

We included 18 trials. The primary outcome was a change in anti-Mullerian hormone and antral follicle count before and after treatment, for which data were unsuitable for meta-analysis. A narrative review showed no consistent direction or size of effect. A meta-analysis for the secondary outcomes showed no evidence of a significant difference between inositol and control groups for any outcome: number of oocytes (mean difference -0.39, 95% confidence interval [CI] -1.11 to 0.33), number of metaphase II oocytes (mean difference 0.29, 95% CI -0.83 to 1.40), number of top grade embryos (risk ratio [RR] 1.02, 95% CI 0.93-1.12), clinical pregnancy rate (RR 1.16, 95% CI 0.87-1.53), and risk of ovarian hyperstimulation syndrome (RR 0.73, 95% CI 0.39-1.37). The quality of evidence was assessed as very low.

CONCLUSIONS

There is insufficient evidence for an effect of inositols on ovarian reserve markers and to support their use as pretreatment before IVF/ICSI in women with polycystic ovary syndrome.

Recent advances in the understanding and management of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a multifaceted condition characterized by chronic anovulation and excess ovarian activity, in contrast to other causes of anovulation that involve ovarian dormancy or primary insufficiency. Recent studies indicated that PCOS is associated with low-grade chronic inflammation and that women with PCOS are at increased risk of non-alcoholic fatty liver disease. The inflammatory and metabolic derangements associated with PCOS are explained in part by the coexistence of insulin resistance and obesity but are further fueled by the androgen excess. New insights into the regulation of hormones and cytokines in muscle and fat tissue support the concept that PCOS is a systemic syndrome. The therapeutic plan should be tailored to the patient phenotype, complaints, and reproductive desire. Of note, the aromatase inhibitor letrozole seems to be more effective than the reference drug clomiphene citrate to treat infertility due to PCOS. Integral management by a multidisciplinary team may help the patients to adhere to lifestyle interventions and thereby reduce body adiposity and recover their metabolic and reproductive health.

The effectiveness of inositol and metformin on infertile polycystic ovary syndrome women with resistant to letrozole

PURPOSE

The purpose is a comparison of effectiveness of myo-inositol and metformin in infertile women with polycystic ovary syndrome (PCOS) treated with letrozole.

METHODS

This study is a randomized single-blind controlled clinical trial undertaken in 150 infertile PCOS women. For all patients, letrozole is prescribed at a dose of 7.5 mg per day from the third day of menstruation for 5 days. Patients who did not ovulate were included and divided into three pretreatment groups: group I(control group), 200 µg of folic acid (as a placebo); group II, 1500 mg of metformin daily plus 200 µg of folic acid, and group III, inositol 2 g plus 200 µg of folic acid received twice daily for 3 months. In the last cycle, 7.5 mg letrozole was prescribed for the induction of ovulation. Primary outcomes were ovary function and pregnancy.

RESULTS

The ovarian function was not significantly different in those groups, whereas the ovarian function of inositol + folic acid group in normal BMI found significantly higher than other BMI spectra. In addition, the ovarian function is significantly higher in the inositol + folic acid group by increasing the infertility duration. The incidence of pregnancy is lower in letrozole + folic acid + inositol group than the other groups; however, it is not significant.

CONCLUSION

The addition of inositol and metformin to the treatment of infertile PCOS women with letrozole resistance improves the ovarian function; however, it is not significant. Of note, inositol was more effective than metformin in patients with normal BMI.

IRCT REGISTRATION NUMBER

IRCT2017070234845N1.

Inositol for subfertile women with polycystic ovary syndrome

BACKGROUND

Subfertile women are highly motivated to try different adjunctive therapies to have a baby, and the widespread perception is that dietary supplements such as myo-inositol (MI) and D-chiro-insoitol (DCI) are associated with only benefit, and not with harm. Many fertility clinicians currently prescribe MI for subfertile women with polycystic ovary syndrome (PCOS) as pre-treatment to in vitro fertilisation (IVF) or for ovulation induction; however no high-quality evidence is available to support this practice. This review assessed the evidence for the effectiveness of inositol in subfertile women with a diagnosis of PCOS.

OBJECTIVES

To evaluate the effectiveness and safety of oral supplementation of inositol for reproductive outcomes among subfertile women with PCOS who are trying to conceive.

SEARCH METHODS

We searched the following databases (to July 2018): Cochrane Gynaecology and Fertility Group (CGFG) Specialised Register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, and AMED. We also checked reference lists and searched the clinical trials registries.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared any type, dose, or combination of oral inositol versus placebo, no treatment/standard treatment, or treatment with another antioxidant, or with a fertility agent, or with another type of inositol, among subfertile women with PCOS.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected eligible studies, extracted data, and assessed risk of bias. The primary outcomes were live birth and adverse effects; secondary outcomes included clinical pregnancy rates and ovulation rates. We pooled studies using a fixed-effect model, and we calculated odds ratios (ORs) with 95% confidence intervals (CIs). We assessed the overall quality of the evidence by applying GRADE criteria.

MAIN RESULTS

We included 13 trials involving 1472 subfertile women with PCOS who were receiving myo-inositol as pre-treatment to IVF (11 trials), or during ovulation induction (two trials). These studies compared MI versus placebo, no treatment/standard, melatonin, metformin, clomiphene citrate, or DCI. The evidence was of 'low' to 'very low' quality. The main limitations were serious risk of bias due to poor reporting of methods, inconsistency, and lack of reporting of clinically relevant outcomes such as live birth and adverse events.We are uncertain whether MI improves live birth rates when compared to standard treatment among women undergoing IVF (OR 2.42, 95% CI 0.75 to 7.83; P = 0.14; 2 RCTs; 84 women; I² = 0%). Very low-quality evidence suggests that for subfertile women with PCOS undergoing pre-treatment to IVF who have an expected live birth rate of 12%, the rate among women using MI would be between 9% and 51%.We are uncertain whether MI may be associated with a decrease in miscarriage rate when compared to standard treatment (OR 0.40, 95% CI 0.19 to 0.86; P = 0.02; 4 RCTs; 535 women; I² = 66%; very low-quality evidence). This suggests that among subfertile women with PCOS with an expected miscarriage rate of 9% who are undergoing pre-treatment to IVF, the rate among women using MI would be between 2% and 8%; however this meta-analysis is based primarily on one study, which reported an unusually high miscarriage rate in the control group, and this has resulted in very high heterogeneity. When we removed this trial from the sensitivity analysis, we no longer saw the effect, and we noted no conclusive differences between MI and standard treatment.Low-quality evidence suggests that MI may be associated with little or no difference in multiple pregnancy rates when compared with standard treatment (OR 1.04, 95% CI 0.63 to 1.71; P = 0.89; 2 RCTs; 425 women). This suggests that among subfertile women with PCOS who are undergoing pre-treatment to IVF, with an expected multiple pregnancy rate of 18%, the rate among women using inositol would be between 12% and 27%.We are uncertain whether MI may be associated with an increased clinical pregnancy rate when compared to standard treatment (OR 1.27, 95% CI 0.87 to 1.85; P = 0.22; 4 RCTs; 535 women; I² = 0%; very low-quality evidence). This suggests that among subfertile women with PCOS who are undergoing pre-treatment to IVF, with an expected clinical pregnancy rate of 26%, the rate among women using MI would be between 24% and 40%. Ovulation rates were not reported for this comparison.Other comparisons included only one trial in each, so for the comparisons MI versus antioxidant, MI versus an insulin-sensitising agent, MI versus an ovulation induction agent, and MI versus another DCI, meta-analysis was not possible.No pooled evidence was available for women with PCOS undergoing ovulation induction, as only single trials performed comparison of the insulin-sensitising agent and the ovulation induction agent.

AUTHORS' CONCLUSIONS

In light of available evidence of very low quality, we are uncertain whether MI improves live birth rate or clinical pregnancy rate in subfertile women with PCOS undergoing IVF pre-treatment taking MI compared to standard treatment. We are also uncertain whether MI decreases miscarriage rates or multiple pregnancy rates for these same women taking MI compared to standard treatment. No pooled evidence is available for use of MI versus placebo, another antioxidant, insulin-sensitising agents, ovulation induction agents, or another type of inositol for women with PCOS undergoing pre-treatment to IVF. No pooled evidence is available for use of MI in women undergoing ovulation induction.

The influence of different inositol stereoisomers supplementation in pregnancy on maternal gestational diabetes mellitus and fetal outcomes in high-risk patients: a randomized controlled trial

Objective: To identify the effects of different dietary inositol stereoisomers on insulin resistance and the development of gestational diabetes mellitus (GDM) in women at high risk for this disorder.Design: A preliminary, prospective, randomized, placebo controlled clinical trial.Participants: Nonobese singleton pregnant women with an elevated fasting glucose in the first or early second trimester were studied throughout pregnancy.Intervention: Supplementation with myo-inositol, d-chiro-inositol, combined myo- and d-chiro-inositol or placebo.Main outcome measure: Development of GDM on a 75 grams oral glucose tolerance test at 24-28 weeks' gestation. Secondary outcome measures were increase in BMI, need for maternal insulin therapy, macrosomia, polyhydramnios, neonatal birthweight and hypoglycemia.Results: The group of women allocated to receive myo-inositol alone had a lower incidence of abnormal oral glucose tolerance test (OGTT). Nine women in the control group (C), one of the myo-inositol (MI), five in d-chiro-inositol (DCI), three in the myo-inositol/D-chiro-inositol group (MI/DCI) required insulin (p = .134). Basal, 1-hour, and 2 hours glycemic controls were significantly lower in exposed groups (p < .001, .011, and .037, respectively). The relative risk reduction related to primary outcome was 0.083, 0.559, and 0.621 for MI, DCI, and MI/DCI groups.Conclusions: This study compared the different inositol stereoisomers in pregnancy to prevent GDM. Noninferiority analysis demonstrated the largest benefit in the myo-inositol group. The relevance of our findings is mainly related to the possibility of an effective approach in GDM. Our study confirmed the efficacy of inositol supplementation in pregnant women at risk for GDM.

Inositol in Polycystic Ovary Syndrome: Restoring Fertility through a Pathophysiology-Based Approach

Myo-inositol (MI) and D-chiro-inositol (DCI) are insulin second messengers, and MI is involved in follicular gonadotropin pathways which orchestrate ovulation. The tissue-specific MI/DCI ratio is modulated by insulin through aromatase and is altered in insulin resistance (IR), with reduced epimerization of MI to DCI in insulin-sensitive tissues. In ovaries, the MI/DCI ratio is 100:1, but is dramatically reduced by insulin-stimulated epimerase in hyperinsulinemic women with polycystic ovary syndrome (PCOS). Inositols have proved to be effective in PCOS, improving metabolic and hormonal state, and restoring spontaneous ovulation. In assisted reproductive technology, inositol improved ovarian stimulation parameters, although data concerning fertility outcomes are conflicting. Given their functions, inositols are an attractive treatment option for PCOS, although well-designed studies on spontaneous and non-spontaneous fertility are needed.

Polycystic Ovary Syndrome: Implication for Drug Metabolism on Assisted Reproductive Techniques-A Literature Review

Polycystic ovary syndrome (PCOS) affects 6-10% of women and could be considered one of the most common endocrine alterations in women of reproductive age. The syndrome is characterized by several hormonal and metabolic alterations, including insulin resistance and hyperandrogenism, which play a severe detrimental role in the patient's fertility. We aimed to offer an overview about drug metabolism in the PCOS population. Nevertheless, we did not find any study that directly compared drug metabolism between PCOS and healthy women. We therefore decided to summarize briefly how hormonal and insulin sensitizer drugs act differently in healthy and PCOS women, who show altered steroidogenesis by theca cells and metabolic imbalance, focusing especially on assisted reproductive techniques. To date, data about drug metabolism in the PCOS population appears to be extremely limited. This important gap could have significant implications for therapeutic approaches and future perspectives: the dosage of drugs commonly used for the treatment of PCOS women should be tailored according to each patient's characteristics; we should implement new clinical trials in order to identify the best pharmacologic strategy for PCOS patients undergoing in vitro fertilization (IVF); it would be advisable to create an international expert panel to investigate the drug metabolism in the PCOS population.

Disruption of INOS, a Gene Encoding myo-Inositol Phosphate Synthase, Causes Male Sterility in Drosophila melanogaster

Inositol is a precursor for the phospholipid membrane component phosphatidylinositol (PI), involved in signal transduction pathways, endoplasmic reticulum stress, and osmoregulation. Alterations of inositol metabolism have been implicated in human reproductive issues, the therapeutic effects of drugs used to treat epilepsy and bipolar disorder, spinal cord defects, and diseases including diabetes and Alzheimer’s. The sole known inositol synthetic enzyme is myo-inositol synthase (MIPS), and the homolog in Drosophilia melanogaster is encoded by the Inos gene. Three identical deletion strains (inos^ΔDF/CyO) were constructed, confirmed by PCR and sequencing, and homozygotes (inos^ΔDF/inos^ΔDF) were shown to lack the transcript encoding the MIPS enzyme. Without inositol, homozygous inos^ΔDF deletion fertilized eggs develop only to the first-instar larval stage. When transferred as pupae to food without inositol, however, inos^ΔDF homozygotes die significantly sooner than wild-type flies. Even with dietary inositol the homozygous inos^ΔDF males are sterile. An inos allele, with a P-element inserted into the first intron, fails to complement this male sterile phenotype. An additional copy of the Inos gene inserted into another chromosome rescues all the phenotypes. These genetic and phenotypic analyses establish D. melanogaster as an excellent model organism in which to examine the role of inositol synthesis in development and reproduction.

The use of inositol(s) isomers in the management of polycystic ovary syndrome: a comprehensive review

The aim of this review is to present the current data about the role of inositols in the management of polycystic ovary syndrome (PCOS) women and in the prevention and treatment of gestational diabetes mellitus (GDM). We analyzed the available literature with key words PCOS, Myo-inositol, D-chiro-inositol, assisted reproductive technologies and GDM. The most recent literature would suggest that Myo-inositol, D-chiro-inositol and their combination in physiological ratio 40:1 could represent an important therapeutic strategy for the improvement of metabolic, hormonal and reproductive aspects of PCOS. In assisted reproductive technologies, however, myo-inositol and the combined treatment, despite D-chiro-inositol monotherapy, are able to improve clinical outcomes. Myo-inositol monotherapy results more effective in preventing and treating GDM even if a larger cohort of studies is needed to better clarify these results.

PCOS and pregnancy: a review of available therapies to improve the outcome of pregnancy in women with polycystic ovary syndrome

INTRODUCTION

Polycystic ovary syndrome (PCOS) is a common cause of female infertility affecting multiple aspects of a women's health.

AREAS COVERED

The aim of this review is to summarize the existing evidence on the treatment of PCOS patients and to examine the actual available therapies to overcome the problem of infertility and improve the outcome of pregnancy. We analyse different treatment strategies such as lifestyle modification, bariatric surgery, insulin sensitizing agents, inositol, clomiphene citrate (CC), aromatase inhibitors, gonadotrophins, laparoscopic ovarian drilling, and assisted reproductive techniques (ART).

EXPERT COMMENTARY

Lifestyle modification is the best initial management for obese PCOS patients seeking pregnancy and insulin sensitizing agents seem to have an important role in treating insulin resistance. Up to now, CC maintains a central role in the induction of ovulation and it has been confirmed as the first-line treatment; the use of gonadotrophins is considered the second-line in CC resistant patients; laparoscopic ovarian drilling is an alternative to gonadotrophins in patients who need laparoscopy for another reason. However, in anovulatory patients, ART represents the only possible alternative to obtain pregnancy. Larger and well-designed studies are needed to clarify the best way to improve the outcome of pregnancy in PCOS women.

Inositol supplement improves clinical pregnancy rate in infertile women undergoing ovulation induction for ICSI or IVF-ET

OBJECTIVE

Pretreatment of myoinositol is a very new method that was evaluated in multiple small studies to manage poor ovarian response in assisted reproduction. This study was to determine the efficacy of myoinositol supplement in infertile women undergoing ovulation induction for intracytoplasmic sperm injection (ICSI) or in vitro fertilization embryo transfer (IVF-ET).

METHODS

A meta-analysis and systematic review of published articles evaluating the efficacy of myo-inositol in patients undergoing ovulation induction for ICSI or IVF-ET was performed.

RESULTS

Seven trials with 935 women were included. Myoinositol supplement was associated with significantly improved clinical pregnancy rate [95% confidence interval (CI), 1.04-1.96; P = .03] and abortion rate (95% CI, 0.08-0.50; P = .0006). Meanwhile, Grade 1 embryos proportion (95% CI, 1.10-2.74; P = .02), germinal vescicle and degenerated oocytes retrieved (95% CI, 0.11-0.86; P = .02), and total amount of ovulation drugs (95% CI, -591.69 to -210.39; P = .001) were also improved in favor of myo-inositol. There were no significant difference in total oocytes retrieved, MII stage oocytes retrieved, stimulation days, and E2 peak level.

CONCLUSIONS

Myoinositol supplement increase clinical pregnancy rate in infertile women undergoing ovulation induction for ICSI or IVF-ET. It may improve the quality of embryos, and reduce the unsuitable oocytes and required amount of stimulation drugs.

Antioxidants for female subfertility

BACKGROUND

A couple may be considered to have fertility problems if they have been trying to conceive for over a year with no success. This may affect up to a quarter of all couples planning a child. It is estimated that for 40% to 50% of couples, subfertility may result from factors affecting women. Antioxidants are thought to reduce the oxidative stress brought on by these conditions. Currently, limited evidence suggests that antioxidants improve fertility, and trials have explored this area with varied results. This review assesses the evidence for the effectiveness of different antioxidants in female subfertility.

OBJECTIVES

To determine whether supplementary oral antioxidants compared with placebo, no treatment/standard treatment or another antioxidant improve fertility outcomes for subfertile women.

SEARCH METHODS

We searched the following databases (from their inception to September 2016) with no language or date restriction: Cochrane Gynaecology and Fertility Group (CGFG) specialised register, the Cochrane Central Register of Studies (CENTRAL CRSO), MEDLINE, Embase, PsycINFO, CINAHL and AMED. We checked reference lists of appropriate studies and searched for ongoing trials in the clinical trials registers.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared any type, dose or combination of oral antioxidant supplement with placebo, no treatment or treatment with another antioxidant, among women attending a reproductive clinic. We excluded trials comparing antioxidants with fertility drugs alone and trials that only included fertile women attending a fertility clinic because of male partner infertility.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected eligible studies, extracted the data and assessed the risk of bias of the included studies. The primary review outcome was live birth; secondary outcomes included clinical pregnancy rates and adverse events. We pooled studies using a fixed-effect model, and calculated odds ratios (ORs) with 95% confidence intervals (CIs) for the dichotomous outcomes of live birth, clinical pregnancy and adverse events. We assessed the overall quality of the evidence by applying GRADE criteria.

MAIN RESULTS

We included 50 trials involving 6510 women. Investigators compared oral antioxidants, including combinations of antioxidants, N-acetyl-cysteine, melatonin, L-arginine, myo-inositol, D-chiro-inositol, carnitine, selenium, vitamin E, vitamin B complex, vitamin C, vitamin D+calcium, CoQ10, pentoxifylline and omega-3-polyunsaturated fatty acids versus placebo, no treatment/standard treatment or another antioxidant.Very low-quality evidence suggests that antioxidants may be associated with an increased live birth rate compared with placebo or no treatment/standard treatment (OR 2.13, 95% CI 1.45 to 3.12, P > 0.001, 8 RCTs, 651 women, I2 = 47%). This suggests that among subfertile women with an expected live birth rate of 20%, the rate among women using antioxidants would be between 26% and 43%.Very low-quality evidence suggests that antioxidants may be associated with an increased clinical pregnancy rate compared with placebo or no treatment/standard treatment (OR 1.52, 95% CI 1.31 to 1.76, P < 0.001, 26 RCTs, 4271 women, I2 = 66%). This suggests that among subfertile women with an expected clinical pregnancy rate of 22%, the rate among women using antioxidants would be between 27% and 33%. Heterogeneity was moderately high.There was insufficient evidence to determine whether there was a difference between the groups in rates of miscarriage (OR 0.79, 95% CI 0.58 to 1.08, P = 0.14, 18 RCTs, 2834 women, I2 = 23%, very low quality evidence). This suggests that, among subfertile women with an expected miscarriage rate of 7%, use of antioxidants would be expected to result in a miscarriage rate of between 4% and 7%. There was also insufficient evidence to determine whether there was a difference between the groups in rates of multiple pregnancy (OR 1.00, 95% CI 0.73 to 1.38, P = 0.98, 8 RCTs, 2163 women, I2 = 4%, very low quality evidence). This suggests that among subfertile women with an expected multiple pregnancy rate of 8%, use of antioxidants would be expected to result in a multiple pregnancy rate between 6% and 11%. Likewise, there was insufficient evidence to determine whether there was a difference between the groups in rates of gastrointestinal disturbances (OR 1.55, 95% CI 0.47 to 5.10, P = 0.47, 3 RCTs, 343 women, I2 = 0%, very low quality evidence). This suggests that among subfertile women with an expected gastrointestinal disturbance rate of 2%, use of antioxidants would be expected to result in a rate between 1% and 11%. Overall adverse events were reported by 35 trials in the meta-analysis, but there was insufficient evidence to draw any conclusions.Only one trial reported on live birth, clinical pregnancy or adverse effects in the antioxidant versus antioxidant comparison, and no conclusions could be drawn.Very low-quality evidence suggests that pentoxifylline may be associated with an increased clinical pregnancy rate compared with placebo or no treatment (OR 2.07, 95% CI 1.20 to 3.56, P = 0.009, 3 RCTs, 276 women, I2 = 0%). This suggests that among subfertile women with an expected clinical pregnancy rate of 25%, the rate among women using pentoxifylline would be between 28% and 53%.There was insufficient evidence to determine whether there was a difference between the groups in rates of miscarriage (OR 1.34, 95% CI 0.46 to 3.90, P = 0.58, 3 RCTs, 276 women, I2 = 0%) or multiple pregnancy (OR 0.78, 95% CI 0.20 to 3.09, one RCT, 112 women, very low quality evidence). This suggests that among subfertile women with an expected miscarriage rate of 4%, the rate among women using pentoxifylline would be between 2% and 15%. For multiple pregnancy, the data suggest that among subfertile women with an expected multiple pregnancy rate of 9%, the rate among women using pentoxifylline would be between 2% and 23%.The overall quality of evidence was limited by serious risk of bias associated with poor reporting of methods, imprecision and inconsistency.

AUTHORS' CONCLUSIONS

In this review, there was very low-quality evidence to show that taking an antioxidant may provide benefit for subfertile women, but insufficient evidence to draw any conclusions about adverse events. At this time, there is limited evidence in support of supplemental oral antioxidants for subfertile women.

Inositol supplementation in women with polycystic ovary syndrome undergoing intracytoplasmic sperm injection: a systematic review and meta-analysis of randomized controlled trials

Polycystic ovary syndrome (PCOS) is a complex and heterogeneous disease that involves menstrual dysfunction and reproductive difficulty, as well as metabolic problems. The aim of this study was to assess the effectiveness of myo-inositol (MYO) and d-chiro-inositol (DCI) on improving oocyte or embryo quality and pregnancy rates for women with PCOS undergoing intracytoplasmic sperm injection (ICSI). We searched the Web of Knowledge, MEDLINE, EMBASE, Pubmed, Scopus and Cochrane databases for all articles published in any language up to March 2017. The selection criteria were as follows: (population) patients with PCOS; (intervention) treatment with inositol (MYO, DCI, or both, with any dose and any duration) in conjunction with an ovulation-inducing agent versus the ovulation-inducing agent alone; (outcome) oocyte and embryo quality; (study design) randomized controlled trials. Of 76 identified studies, eight RCTs were included for analysis comprising 1019 women with PCOS. MYO supplementation was insufficient to improve oocyte quality (OR 2.2051; 95% CI 0.8260 to 5.8868), embryo quality (OR 1.6231, 95% CI 0.3926 to 6.7097), or pregnancy rate (OR 1.2832, 95% CI 0.8692 to 1.8944). Future studies of appropriate dose, size and duration of DCI are vital to clarify its the role in the management of PCOS.

Polycystic Ovary Syndrome: Insights into the Therapeutic Approach with Inositols

Polycystic ovary syndrome (PCOS) is characterized by hormonal abnormalities that cause menstrual irregularity and reduce ovulation rate and fertility, associated to insulin resistance. Myo-inositol (cis-1,2,3,5-trans-4,6-cyclohexanehexol, MI) and D-chiro-inositol (cis-1,2,4-trans-3,5,6-cyclohexanehexol, DCI) represent promising treatments for PCOS, having shown some therapeutic benefits without substantial side effects. Because the use of inositols for treating PCOS is widespread, a deep understanding of this treatment option is needed, both in terms of potential mechanisms and efficacy. This review summarizes the current knowledge on the biological effects of MI and DCI and the results obtained from relevant intervention studies with inositols in PCOS. Based on the published results, both MI and DCI represent potential valid therapeutic approaches for the treatment of insulin resistance and its associated metabolic and reproductive disorders, such as those occurring in women affected by PCOS. Furthermore, the combination MI/DCI seems also effective and might be even superior to either inositol species alone. However, based on available data, a particular MI:DCI ratio to be administered to PCOS patients cannot be established. Further studies are then necessary to understand the real contents of MI or DCI uptaken by the ovary following oral administration in order to identify optimal doses and/or combination ratios.

Inositol and In Vitro Fertilization with Embryo Transfer

Recently, studies on inositol supplementation during in vitro fertilization program (IVF) have gained particular importance due to the effect of this molecule on reducing insulin resistance improving ovarian function, oocyte quality, and embryo and pregnancy rates and reducing gonadotropin amount during stimulation. Inositol and its isoforms, especially myoinositol (MYO), are often used as prestimulation therapy in infertile patients undergoing IVF cycle. Inositol supplementation started three months before ovarian stimulation, resulting in significant improvements in hormonal responses, reducing the amount of FSH necessary for optimal follicle development and serum levels of 17beta-estradiol measured the day of hCG injection. As shown by growing number of trials, MYO supplementation improves oocyte quality by reducing the number of degenerated and immature oocytes, in this way increasing the quality of embryos produced. Inositol can also improve the quality of sperm parameters in those patients affected by oligoasthenoteratozoospermia.

Combining treatment with myo-inositol and D-chiro-inositol (40:1) is effective in restoring ovary function and metabolic balance in PCOS patients

Polycystic ovary syndrome (PCOS), a relevant cause of infertility, is a heterogeneous, endocrine disorder affecting up to 10-15% of women in reproductive age. Besides hyperandrogenism, insulin resistance (IR) plays a key role in such syndrome. Insulin-sensitizing drugs, such as Metformin, are effective in treating hyper-insulinemic PCOS patients. Recently, inositols - myo-inositol (MI) and D-chiro-inositol (DCI) - have shown to be an efficient and safe alternative in PCOS management, as both inositol isoforms are able to counteract downstream consequences of insulin resistance. Yet, whereas DCI contributes in mediating insulin activity mainly on non-ovarian tissues, MI displays specific effects on ovary, chiefly by modulating glucose metabolism and FSH-signaling. Moreover, MI may also improve ovarian functions by modulating steroid metabolism through non-insulin-dependent pathways. As DCI and MI activity likely involves different biological mechanisms, both inositol isoforms can be synergistically integrated according to a multitargeted design, by combining MI and DCI in a ratio corresponding to their physiological plasma relative amount (40:1). New experimental and clinical evidence with MI plus DCI evidenced the suitability of such integrated approach, and provided promising results. Further studies need to investigate thoroughly the molecular mechanism and confirm such preliminary data.

Inositol and human reproduction. From cellular metabolism to clinical use

Inositol is an organic compound of high biological importance that is widely distributed in nature. It belongs to the sugar family and is mainly represented by its two dominant stereoisomers: myo-inositol and D-chiro-inositol that are found in the organism in the physiological serum ratio 40:1. Inositol and its derivatives are important components of the structural phospholipids of the cell membranes and are precursors of the second messengers of many metabolic pathways. A high concentration of myoinositol is found in the follicular fluid and in semen. Inositol deficiency and the impairment of the inositol-dependent pathways may play an important role in the pathogenesis of insulin resistance and hypothyroidism. The results of the research also point out the potential beneficial role of inositol supplementation in polycystic ovarian syndrome and in the context of assisted reproduction technologies and in vitro fertilization. The main aim of the article is to overview the major inositol-dependent metabolic pathways and to discuss its importance for reproduction.

The inositols and polycystic ovary syndrome

This review describes the rationale, biochemical, and clinical data related to the use of inositols in polycystic ovary syndrome (PCOS). It covers studies related to the mechanism of action of myo-inositol and D-chiro-inositol (MDI), with randomized controlled trials conducted in women with PCOS, and utilizes these data to suggest pragmatic indications and methods for using MDI combination in PCOS. Rationally crafted inositol combinations have a potential role to play in maintaining metabolic, endocrine, and reproductive health in women with PCOS.

How to Achieve High-Quality Oocytes? The Key Role of Myo-Inositol and Melatonin

Assisted reproductive technologies (ART) have experienced growing interest from infertile patients seeking to become pregnant. The quality of oocytes plays a pivotal role in determining ART outcomes. Although many authors have studied how supplementation therapy may affect this important parameter for both in vivo and in vitro models, data are not yet robust enough to support firm conclusions. Regarding this last point, in this review our objective has been to evaluate the state of the art regarding supplementation with melatonin and myo-inositol in order to improve oocyte quality during ART. On the one hand, the antioxidant effect of melatonin is well known as being useful during ovulation and oocyte incubation, two occasions with a high level of oxidative stress. On the other hand, myo-inositol is important in cellular structure and in cellular signaling pathways. Our analysis suggests that the use of these two molecules may significantly improve the quality of oocytes and the quality of embryos: melatonin seems to raise the fertilization rate, and myo-inositol improves the pregnancy rate, although all published studies do not fully agree with these conclusions. However, previous studies have demonstrated that cotreatment improves these results compared with melatonin alone or myo-inositol alone. We recommend that further studies be performed in order to confirm these positive outcomes in routine ART treatment.

Inositol's and other nutraceuticals' synergistic actions counteract insulin resistance in polycystic ovarian syndrome and metabolic syndrome: state-of-the-art and future perspectives

The incidence of metabolic syndrome (MetS), type II diabetes (T2D) and polycystic ovarian syndrome (PCOS) has been progressively increasing. Insulin resistance (InsR) seems to play a key role in a majority of phenotypes of these conditions, altering metabolic homeostasis, within muscle, liver, adipose and other tissues. Hyperinsulinemia is often associated with InsR and causes hormonal imbalances especially within ovaries and adrenals. Inositol is a polyalcohol, naturally occurring as nine stereoisomers, including D-chiro-inositol (DCI) and myo-inositol (MI), which have prominent roles in the metabolism of glucose and free fatty acids. MI and DCI have been classified as insulin-sensitizers and seem to adequately counteract several InsR-related metabolic alterations with a safe nutraceutical profile. Based on our analysis of selected studies that investigated MI and/or DCI, we conclude that supplementation with MI and/or DCI complement each other in their metabolic actions and act in synergy with other insulin sensitizing drugs and/or nutraceuticals. Nevertheless, considering the possible severe bias due to different methodologies across published studies, we conclude that there is a need for further studies on larger cohorts and with greater statistical power. These should further clarify outcomes and suitable therapeutic dosages of MI and DCI, possibly based on each patient's clinical status.

The "Other" Inositols and Their Phosphates: Synthesis, Biology, and Medicine (with Recent Advances in myo-Inositol Chemistry)

Cell signaling via inositol phosphates, in particular via the second messenger myo-inositol 1,4,5-trisphosphate, and phosphoinositides comprises a huge field of biology. Of the nine 1,2,3,4,5,6-cyclohexanehexol isomers, myo-inositol is pre-eminent, with "other" inositols (cis-, epi-, allo-, muco-, neo-, L-chiro-, D-chiro-, and scyllo-) and derivatives rarer or thought not to exist in nature. However, neo- and d-chiro-inositol hexakisphosphates were recently revealed in both terrestrial and aquatic ecosystems, thus highlighting the paucity of knowledge of the origins and potential biological functions of such stereoisomers, a prevalent group of environmental organic phosphates, and their parent inositols. Some "other" inositols are medically relevant, for example, scyllo-inositol (neurodegenerative diseases) and d-chiro-inositol (diabetes). It is timely to consider exploration of the roles and applications of the "other" isomers and their derivatives, likely by exploiting techniques now well developed for the myo series.

Insulin-Sensitizers, Polycystic Ovary Syndrome and Gynaecological Cancer Risk

Preclinical, early phase clinical trials and epidemiological evidence support the potential role of insulin-sensitizers in cancer prevention and treatment. Insulin-sensitizers improve the metabolic and hormonal profile in PCOS patients and may also act as anticancer agents, especially in cancers associated with hyperinsulinemia and oestrogen dependent cancers. Several lines of evidence support the protection against cancer exerted by dietary inositol, in particular inositol hexaphosphate. Metformin, thiazolidinediones, and myoinositol postreceptor signaling may exhibit direct inhibitory effects on cancer cell growth. AMPK, the main molecular target of metformin, is emerging as a target for cancer prevention and treatment. PCOS may be correlated to an increased risk for developing ovarian and endometrial cancer (up to threefold). Several studies have demonstrated an increase in mortality rate from ovarian cancer among overweight/obese PCOS women compared with normal weight women. Long-term use of metformin has been associated with lower rates of ovarian cancer. Considering the evidence supporting a higher risk of gynaecological cancer in PCOS women, we discuss the potential use of insulin-sensitizers as a potential tool for chemoprevention, hypothesizing a possible rationale through which insulin-sensitizers may inhibit tumourigenesis.

Inositol Treatment and ART Outcomes in Women with PCOS

Polycystic ovary syndrome (PCOS) affects 5-10% of women in reproductive age and is characterized by oligo/amenorrhea, androgen excess, insulin resistance, and typical polycystic ovarian morphology. It is the most common cause of infertility secondary to ovulatory dysfunction. The underlying etiology is still unknown but is believed to be multifactorial. Insulin-sensitizing compounds such as inositol, a B-complex vitamin, and its stereoisomers (myo-inositol and D-chiro-inositol) have been studied as an effective treatment of PCOS. Administration of inositol in PCOS has been shown to improve not only the metabolic and hormonal parameters but also ovarian function and the response to assisted-reproductive technology (ART). Accumulating evidence suggests that it is also capable of improving folliculogenesis and embryo quality and increasing the mature oocyte yield following ovarian stimulation for ART in women with PCOS. In the current review, we collate the evidence and summarize our current knowledge on ovarian stimulation and ART outcomes following inositol treatment in women with PCOS undergoing in vitro fertilization (IVF) and/or intracytoplasmic sperm injection (ICSI).