Dietary nutrient intake and nutritional status in women with infertility: a cross-sectional study

Infertility affects 17.5% of reproductive-age couples and represents a global health challenge with a complex etiology. While nutritional status and diet are recognized as modifiable factors, evidence in specialized clinical settings remains limited. This study was designed under the hypothesis that dietary nutrient intake is significantly associated with the hormonal and anthropometric profile of women seeking fertility treatment. We aimed to address this gap by analyzing these associations in a well-characterized clinical cohort. A cross-sectional study was conducted with 97 women (aged 18–40 years) diagnosed with infertility at Marina Salud Hospital (Spain) between 2022 and 2024. Dietary intake and body composition were assessed using a validated 137-item FFQ and standardized anthropometric measurements (BIA). Reproductive hormones were analyzed from follicular-phase blood samples. Statistical analyses included Spearman correlations and linear regression models adjusted for total energy intake, physical activity, smoking status, and BMI (p < 0.05). Participants had a mean BMI of 25.5 ± 5.6 kg/m2, with 23.7% overweight and 17.5% obese. Body fat (35.9 ± 9.3%) and visceral fat (5.5 ± 2.3%) percentages exceeded recommended values. Multivariate analysis showed that higher intakes of riboflavin (β = 0.665, p = 0.042) and calcium (β = 0.004, p = 0.012) were significantly associated with increased muscle mass percentage. Additionally, vitamin E intake was inversely associated with hip circumference (β = − 0.773, p = 0.004). Regarding hormonal markers, vitamin E showed a significant inverse association with prolactin levels, which remained robust after adjusting for potential confounders (β = − 0.501, p = 0.008). No other nutrient–hormone associations reached significance after adjustment. These findings suggest that specific nutrients, such as riboflavin and vitamin E, are associated with a more favorable body composition and hormonal regulation in women with infertility. Although the cross-sectional design limits causal inference, these results highlight potential modifiable targets for personalized nutritional support in reproductive health. Future longitudinal studies are warranted to confirm these exploratory findings.