Female infertility and diet, is there a role for a personalized nutritional approach in assisted reproductive technologies?  Original paper

What was reviewed?

This comprehensive narrative review synthesized current research on the interplay between diet, genetics, epigenetics, and the microbiome in female infertility, with a focus on the impact of dietary patterns and nutrients on reproductive health and assisted reproductive technology (ART) outcomes. It critically appraised evidence from observational studies, randomized controlled trials, and animal research, covering macronutrients (proteins, carbohydrates, fats), micronutrients (vitamins, minerals), dietary patterns (Mediterranean, Western), and specific dietary components, such as prebiotics and probiotics. The review also discussed how nutritional factors interface with genetic and epigenetic mechanisms and the gut and vaginal microbiome, ultimately influencing female fertility and ART success.

Who was reviewed?

The review encompassed studies involving a diverse range of populations, including healthy women of reproductive age, women experiencing infertility, those undergoing ART procedures (e.g., IVF, ICSI), and relevant animal models (mice, rats, cattle, macaques, Drosophila). The reviewed evidence included large cohort studies (e.g., Nurses’ Health Study II), randomized controlled trials, and mechanistic studies exploring molecular and microbial pathways. The analysis particularly focused on women with different dietary patterns, micronutrient statuses, and genetic backgrounds, as well as those with specific reproductive disorders such as PCOS.

Most important findings

The review found that dietary patterns and specific nutrients play a significant role in female reproductive health and ART outcomes. Adherence to the Mediterranean diet, rich in plant-based foods, PUFAs, whole grains, and micronutrients, was consistently associated with improved ovulatory function, higher pregnancy rates, and enhanced ART outcomes, potentially mediated by anti-inflammatory and antioxidant effects. Conversely, Western diets high in trans fats, refined sugars, and red meat were linked to ovulatory disorders and lower fertility. Micronutrients such as folate, vitamin D, zinc, and selenium were positively associated with reproductive hormone profiles, oocyte quality, and ART success, though evidence on vitamin D was mixed. Genetic polymorphisms influenced folate metabolism and ART outcomes, highlighting the potential for personalized nutrition. Epigenetic modifications such as DNA methylation changes induced by dietary folate or histone modification by micronutrients were implicated in oocyte and embryo quality. Microbiome studies revealed that dietary fiber and prebiotic supplementation improved ART outcomes by enriching beneficial gut bacteria and reducing potentially harmful taxa. Higher follicular fluid levels of the microbial metabolite TMAO were associated with poorer embryo quality, implicating the gut microbiome in reproductive success. Favorable vaginal microbiome profiles, dominated by Lactobacillus species, were predictive of higher ART pregnancy rates.

Key implications

The review underscores the importance of considering diet, genomics, epigenetic status, and the microbiome in the management of female infertility and ART. Personalizing nutritional interventions based on genetic and microbial signatures holds promise for optimizing fertility treatments. Clinicians should be aware that dietary counseling, favoring Mediterranean-style diets, adequate intake of key micronutrients, and possibly prebiotic/probiotic interventions may improve reproductive outcomes. However, the heterogeneity of study designs and populations, as well as limited interventional evidence, means that further research is needed to establish precise, individualized nutritional guidelines for women seeking to conceive, particularly those undergoing ART.