Background: For over two decades we have been trying to study and demonstrate the role of the gut microbiota in the onset of cardiovascular, autoimmune, infectious and neurobiological diseases, and more generally the clinical efficacy. 

Materials and methods: All clinical trials and randomized controlled trials were selected up to March 30, 2023, for a useful total of 45 studies. 

Results: Significant evidence emerges in the literature that supports the therapeutic use for clinical purposes of prebiotics and probiotics even during gestation and within the first 2 years of life, of specific bacterial strains of Lactobacillus and Bifidobacterium (with almost no definite evidence for S. boulardii) to promote proper intestinal eubiosis, slow down inflammatory and infectious processes, including those of an allergic nature, and prevent or ameliorate disease states such as that of gestational diabetes mellitus, sepsis, necrosis, and preeclampsia. In addition, the use of high-fat polyunsaturated fatty acid (HF-PUFA) blends from fish oil, fermented milk supplemented with probiotic strains, and galactooligosaccharides/polydextrose (GOS/PDX) seems useful. 

Conclusions: There emerges, therefore, the need, in such a varied and contradictory landscape, to design a research project that takes into account, first of all, a significant and representative population sample, but above all, one that does not underestimate the critical issues mentioned above, to address with a scientific method the proper and functional use of prebiotics and probiotics in the neonatal and obstetrical fields in general; further studies that can confirm and expand scientific knowledge in this particular field are therefore needed.