Can Dietary Patterns Impact Fertility Outcomes? A Systematic Review and Meta-Analysis

Abstract

There are conflicting results on the effect of diet on fertility. This study aimed to assess the effect of different dietary patterns on fertility outcomes in populations who conceive spontaneously and those requiring assisted reproductive technology (ART). A systematic search and meta-analysis were performed for studies investigating dietary patterns or whole diets in reproductive aged women requiring ART or conceived naturally. Outcomes were live births, pregnancy rates and infertility rates. In amount of 15,396 studies were screened with 11 eligible studies. Ten different diet patterns were grouped broadly into categories: Mediterranean, Healthy or Unhealthy. For the Mediterranean diet, on excluding high risk-of-bias studies (n = 3), higher adherence was associated with improved live birth/pregnancy rates in ART [OR 1.91 (95% CI 1.14–3.19, I2 43%)] (n = 2). Adherence to various Healthy diets was associated with improved ART outcomes (ProFertility diet and Dutch Dietary Guidelines) and natural conception outcomes (Fertility diet). However, due to the variability in Healthy diets’ components, results were not pooled. Studies demonstrated preliminary evidence for the role of dietary patterns or whole diets in improving pregnancy and live birth rates. However, due to heterogeneity across the literature it is currently unclear which diet patterns are associated with improvements in fertility and ART outcomes.

Do Popular Diets Impact Fertility?

“…In order to address these conflicting results, two recent meta-analyses were conducted to examine the impact of MD adherence on pregnancy and live births [ 27 , 28 ]. The meta-analysis conducted by Winter et al [ 27 ], which included five studies in populations receiving assisted reproductive treatment, concluded that high MD adherence may increase clinical pregnancy and the live birth rate by approximately one-third (OR 1.27, 95%CI 0.82–1.98, I 2 = 60%), which increased to two-thirds (OR 1.91, 95%CI 1.14–3.19, I 2 = 43%) after excluding three studies considered to present a high risk of bias. Contrary to these results, Muffone et al [ 28 ] could not establish a link between MD adherence and pregnancy outcomes (live births and clinical pregnancy), due to the heterogeneity of the studies.…”

“…This nutritional plan appears to be unrelated to female reproductive outcomes, according to the literature [ 19 , 27 ]. Nevertheless, different observational studies have shown a positive association between the highest adherence to the Western diet and a higher risk of PCOS and clinical features linked with this condition [ 73 , 74 ].…”

Baseline Dietary Patterns and Infertility Treatment Outcomes—Setting the Right Foundation

“…The design of the study by Salas-Huetos et al 1 does not distinguish between and within different racial and ethnic groups, nor does it address the complex factors that affect what and how people eat. 8 Due to the lack of diversity of participants, the study is limited in its overall generalizability, including individuals in geographically restricted regions, low-income settings, or racially or ethnically minoritized populations. This shortcoming is not unique in clinical research, as many researchers fail to broaden their lens to multiple layers of diversity during participant recruitment.…”

“…This highlights the importance of social determinants of health on clinical outcomes. The design of the study by Salas-Huetos et al does not distinguish between and within different racial and ethnic groups, nor does it address the complex factors that affect what and how people eat . Due to the lack of diversity of participants, the study is limited in its overall generalizability, including individuals in geographically restricted regions, low-income settings, or racially or ethnically minoritized populations.…”

How the intricate relationship between nutrition and hormonal equilibrium significantly influences endocrine and reproductive health in adolescent girls

“…Similar to obesity, underweight individuals may also face challenges associated with the regulation of the endocrine system, including the HPG- and growth hormone—insulin-like growth factor (IGF)-1 axis, thyroid and adrenal functions. These factors can influence pubertal development, sexual characteristics, and fertility ( 22 , 23 ).…”