Diet in assisted reproductive technology: what should we recommend? A systematic review from current evidence to tailored nutritional approaches for enhancing reproductive success.

Over recent years, nutrition has been increasingly recognized as a modifiable factor influencing fertility and the outcomes of assisted reproductive technology (ART). Preconception dietary habits in both sexes affect body weight, metabolic health and the chances of achieving pregnancy. To systematically review the current evidence on the role of diet in ART, a systematic search was conducted in PubMed, Web of Science and Embase up to February 2025. Eligible studies included peer-reviewed clinical research assessing dietary interventions in couples undergoing ART. A total of 39 original studies were included. Findings suggest that adherence to healthy dietary patterns improves ART outcomes. Consistent effects on live birth, however, have not been demonstrated. Conversely, unhealthy patterns, notably the Western diet, are associated with poorer outcomes. Evidence for exclusion diets or specific nutrients is inconclusive, with potential benefits observed only in selected subgroups, such as women with polycystic ovary syndrome or coeliac disease. In conclusion, no single dietary approach is proven to enhance IVF success, nor is macronutrient exclusion supported. Personalized dietary strategies, including tailored nutrition, micronutrient supplementation and precision probiotics, are needed to address gut dysbiosis and metabolic disturbances, thereby improving ART outcomes and supporting long-term reproductive health.