Myo-Inositol for the Prevention of Gestational Diabetes Mellitus. A Brief Review

Delphi consensus on the diagnostic criteria of polycystic ovary syndrome

Facchinetti F et al., 2025 · Journal of endocrinological investigation

To gather the current opinion among Italian gynecologists and endocrinologists regarding the definition, diagnosis, and treatment of polycystic ovary syndrome (PCOS). A Delphi survey consisting of 26 statements was designed by a nine-member panel (consisting of members from the Italian Society of Endocrinology (SIE) and the Experts Group AQon Inositol in Basic and Clinical Research and on PCOS (EGOI-PCOS)) and distributed to 102 experts in PCOS across the fields of gynecology and endocrinology. Consensus was defined as an agreement between at least 70% of responders. Participants completed three rounds of statements, ranking their level of agreement. Of the initial 26 statements, 25 reached an adequate consensus, with an overall response rate of 73%. The statements were divided into three sections: definition and current understanding, diagnosis, and treatment. Of the statements that reached consensus, near total agreement was reached in the first two sections, whereas there was a divergence of opinion in terms of optimum treatment strategy between the gynecology and endocrinology subgroups. It was agreed that the current clinical guidelines are inadequate for clinical and scientific practice, with most responders advocating for the inclusion of metabolic factors. Furthermore, the consensus opinion advocated for the diversification of hyperandrogenic vs. non-hyperandrogenic phenotypes. This survey gives a snapshot of the current understanding of PCOS in the Italian healthcare community.

Myo-inositol supplementation to prevent gestational diabetes in overweight non-obese women: bioelectrical impedance analysis, metabolic aspects, obstetric and neonatal outcomes - a randomized and open-label, placebo-controlled clinical trial

Vitale SG et al., 2020 · Int J Food Sci Nutr

This study aims to evaluate the effects of myo-inositol supplementation on gestational diabetes mellitus (GDM) rates and body water distribution in overweight non-obese women. 223 overweight non-obese women pregnant were randomly assigned to the treatment group (2 g of myo-inositol plus 200 µg of folic acid) or to the placebo one (200 µg of folic acid). The treatment lasted until three weeks after delivery. A tetrapolar impedance analyser was used to study body composition. The incidence of GDM was significantly reduced in the myo-inositol group compared with the placebo group. There was a significant increase in TBW, ECW and ICW values in the placebo group compared to the myo-inositol group. We have recorded a significant reduction in the overall incidence of pregnancy-induced hypertension in the myo-inositol group compared with the placebo group. Our results demonstrate the effectiveness of myo-inositol supplementation in preventing GDM in overweight non-obese pregnant women.

Myo-inositol may prevent gestational diabetes onset in overweight women: a randomized, controlled trial

Santamaria A et al., 2015 · J Matern Fetal Neonatal Med

To evaluate whether myo-inositol supplementation may reduce gestational diabetes mellitus (GDM) rate in overweight women. In an open-label, randomized trial, myo-inositol (2 g plus 200 μg folic acid twice a day) or placebo (200 μg folic acid twice a day) was administered from the first trimester to delivery in pregnant overweight non-obese women (pre-pregnancy body mass index ≥ 25 and < 30 kg/m(2)). The primary outcome was the incidence of GDM. From January 2012 to December 2014, 220 pregnant women were randomized at two Italian University hospitals, 110 to myo-inositol and 110 to placebo. The incidence of GDM was significantly lower in the myo-inositol group compared to the placebo group (11.6% versus 27.4%, respectively, p = 0.004). Myo-inositol treatment was associated with a 67% risk reduction of developing GDM (OR 0.33; 95% CI 0.15-0.70). Myo-inositol supplementation, administered since early pregnancy, reduces GDM incidence in overweight non-obese women.

Myo-inositol Supplementation for Prevention of Gestational Diabetes in Obese Pregnant Women: A Randomized Controlled Trial

D'Anna R et al., 2015 · Obstet Gynecol

To evaluate whether myo-inositol supplementation, an insulin sensitizer, reduces the rate of gestational diabetes mellitus (GDM) and lowers insulin resistance in obese pregnant women. In an open-label, randomized trial, myo-inositol (2 g plus 200 micrograms folic acid twice a day) or placebo (200 micrograms folic acid twice a day) was administered from the first trimester to delivery in pregnant obese women (prepregnancy body mass index 30 or greater. We calculated that 101 women in each arm would be required to demonstrate a 65% GDM reduction in the myo-inositol group with a statistical power of 80% (α=0.05). The primary outcomes were the incidence of GDM and the change in insulin resistance from enrollment until the diagnostic oral glucose tolerance test. From January 2011 to April 2014, 220 pregnant women at 12-13 weeks of gestation were randomized at two Italian university hospitals, 110 to myo-inositol and 110 to placebo. Most characteristics were similar between groups. The GDM rate was significantly reduced in the myo-inositol group compared with the control group, 14.0% compared with 33.6%, respectively (P=.001; odds ratio 0.34, 95% confidence interval 0.17-0.68). Furthermore, women treated with myo-inositol showed a significantly greater reduction in the homeostasis model assessment of insulin resistance compared with the control group, -1.0±3.1 compared with 0.1±1.8 (P=.048). Myo-inositol supplementation, started in the first trimester, in obese pregnant women seems to reduce the incidence in GDM through a reduction of insulin resistance. CLINICAL ClinicalTrials.gov, www.clinicaltrials.gov, NCT01047982.

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

Celentano C et al., 2018 · J Matern Fetal Neonatal Med

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. Nonobese singleton pregnant women with an elevated fasting glucose in the first or early second trimester were studied throughout pregnancy. Supplementation with myo-inositol, d-chiro-inositol, combined myoand d-chiro-inositol or placebo.Main 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. 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. 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.

The influence of D-chiro-inositol and D-myo-inositol in pregnant women with glucose intolerance

Dell'Edera D et al., 2017 · Biomed Rep · Free full text on PubMed Central

The aim of the present study was to demonstrate that the use of inositol and folic acid from the first trimester of pregnancy, counteracts the onset of gestational diabetes mellitus (GDM) in women at risk, preserving the infants from macrosomia, hypoglycemia and preterm delivery. The authors collected data from the pregnant women at the laboratory (Unit of Cytogenic and Molecular Genetics), from January 2014 to April 2016, all with first trimester fasting plasma glucose (FPG) >92 mg/dl. A total of 40 women were treated with 250 mg/day D-chiro-inositol, 1.75 g/day D-myo-inositol, 12.5 mg/day zinc, 10 mg/day methylsulfonylmethane, 400 µg/day 5-methyltetrahydrofolic acid. The other 43 women (control group) were treated with only 400 µg/day folic acid. The primary outcome measure was the incidence of maternal GDM. The secondary outcome measures were the incidence of fetal macrosomia, preterm delivery and neonatal hypoglycemia. At the 24th week of pregnancy, the incidence of maternal GDM was recorded in 18 women in the control group and in 5 women in the treated group [relative risk (RR)=3.35; 95% confidence interval (CI)=1.37-8.17; P=0.0028). A significant difference was observed between treated and control groups in terms of risk of macrosomia. A total of seven infants in the control group, and two in the treated group, weighed >4,000 g (RR=5,12; 95% CI=1.21-21.68; P=0.0099). No significant difference was identified between two groups, regarding the other two secondary outcomes, neonatal hypoglycemia (RR=4.650; 95% CI=0.57-38.11; P=0.1086) and preterm delivery (RR=1.74; 95% CI=0.83-3.66; P=0.1301). The current study demonstrated the potential benefit of supplementation with the association of D-chiro-inositol and D-myo-inositol in pregnant 'at risk' women, with first trimester FPG >92 mg/dl, in preventing the onset of maternal GDM and macrosomia in newborns.

The effect of myoinositol supplementation on insulin resistance in patients with gestational diabetes

Corrado F et al., 2011 · Diabetic medicine : a journal of the British Diabetic Association

To test the hypothesis that myoinositol supplementation will improve insulin sensitivity as measured by markers of insulin resistance such as homeostasis model assessment of insulin resistance and adiponectin in women with gestational diabetes. The trial was carried out in diet-treated patients with gestational diabetes diagnosed in our department between April 2008 and September 2009. Subjects were randomly assigned to receive either myoinositol supplementation (4 g daily) plus folic acid (400 μg daily)-the study group-or folic acid only (400 μg daily)-the control group. Both groups received the same diet prescription. Homeostasis model assessment of insulin resistance and adiponectin were assayed while fasting at the time of the diagnostic oral glucose tolerance test and after 8 weeks of treatment. There were 69 evaluable patients, 24 in the study group and 45 in the control group. Fasting glucose and insulin, and consequently homeostasis model assessment of insulin resistance, decreased in both groups (50% in the study group vs. 29% in the control group), but the decline in the study group was significantly greater than that in the control group (P = 0.0001). Adiponectin increased in the myoinositol group while it decreased in the control group (P = 0.009). Myoinositol improves insulin resistance in patients with gestational diabetes.

Myo-inositol for insulin resistance, metabolic syndrome, polycystic ovary syndrome and gestational diabetes

DiNicolantonio JJ et al., 2022 · Open heart · Free full text on PubMed Central