Introduction:

Gestational diabetes mellitus (GDM) affects between 5 and 40% of pregnant women. Recently different interventions with nutritional supplements have been evaluated for prevention of GDM.

Aim:

To perform a synthesis of the evidence on the efficacy of nutritional supplements (myo-inositol, probiotics, and vitamin D) in the prevention of GDM.

Methods:

A systematic search in PubMed and Cochrane library was performed, including systematic reviews of randomized clinical trials (RCTs), published in English or Spanish until May 2020, using the keywords: "prevention", "gestational diabetes", "hyperglycemia and pregnancy", "supplementation", "probiotics", "myo-inositol" and "vitamin D".

Results:

10 systematic reviews that met the inclusion criteria were analyzed. Myo-inositol supplementation compared to placebo decreased the incidence of GDM (RR: 0.44 [0.27-0.87]; five RCTs), low quality of evidence. Although the supplementation with vitamin D or probiotics during pregnancy could reduce the incidence of GDM the evidence is limited.

Conclusions:

Myo-inositol supplementation is effective for prevention of GDM in high-risk women. Supplementation with vitamin D or probiotics probably decreases the incidence of GDM.