{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T12:32:03Z","timestamp":1789475523654,"version":"build-2803163510"},"reference-count":26,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T00:00:00Z","timestamp":1783641600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Nutr."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Dietary phytochemicals possess antioxidant and anti-inflammatory properties, yet their relationship with female infertility remains unclear. We examined the association between the Dietary Phytochemical Index (DPI) and infertility, and whether oxidative stress\/inflammatory biomarkers mediate this link.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      This case\u2013control study included 400 women (200 infertile, 200 fertile). Cases were clinically diagnosed infertility patients; controls had \u22651 live birth. DPI was calculated from food-frequency questionnaires. Fasting biomarkers (MDA, HOMA-IR, hs-CRP, IL-6, TNF-\n                      <jats:italic>\u03b1<\/jats:italic>\n                      , TAC) were measured. Logistic regression evaluated DPI\u2013infertility associations, and bootstrap mediation analysis tested indirect effects through biomarkers.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Infertile women had significantly lower DPI (28.2\u202f\u00b1\u202f8.4 vs. 34.1\u202f\u00b1\u202f9.8,\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;lt;\u202f0.001). Each 1\u202funit increase in DPI was associated with 7% lower odds of infertility (OR 0.931, 95% CI: 0.909\u20130.953). Expressed per 10 unit increment (a more clinically interpretable change), this corresponds to approximately 48% lower odds (OR 0.48, 95% CI: 0.39\u20130.59). Women in the highest DPI tertile had 80% lower odds than those in the lowest (OR 0.205, 95% CI 0.119\u20130.352), with a significant dose\u2013response trend (\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;lt;\u202f0.001). DPI was inversely associated with MDA, HOMA-IR, hs-CRP, and IL-6 (all\n                      <jats:italic>p<\/jats:italic>\n                      \u202f&amp;lt;\u202f0.05), but none of the examined biomarkers significantly mediated the DPI\u2013infertility association (all indirect effect 95% CIs included zero; maximum proportion mediated: 12.6% for HOMA-IR). The direct effect of DPI remained significant in all models.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Higher dietary phytochemical intake shows a strong independent association with lower infertility odds in this exploratory case\u2013control study. Causal inference is precluded by design limitations. In exploratory mediation analyses, circulating oxidative stress and inflammatory biomarkers did not significantly mediate this association; however, this finding does not exclude local tissue level or alternative mechanistic pathways. Prospective studies are needed to establish causality and elucidate mechanisms.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fnut.2026.1865952","type":"journal-article","created":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T04:25:56Z","timestamp":1783657556000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Higher dietary phytochemical index is associated with lower odds of infertility: a case\u2013control study"],"prefix":"10.3389","volume":"13","author":[{"given":"Yanfei","family":"Ji","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynecology, The Second Hospital of Shanxi Medical University","place":["Taiyuan, Shanxi Province, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hui","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, The Second Hospital of Shanxi Medical University","place":["Taiyuan, Shanxi Province, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,10]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"114","DOI":"10.1186\/s12905-019-0805-3","article-title":"An investigation of the effects of infertility on women\u2019s quality of life: a case-control study","volume":"19","author":"Bakhtiyar","year":"2019","journal-title":"BMC Womens Health"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"1506","DOI":"10.1093\/humrep\/dem046","article-title":"International estimates of infertility prevalence and treatment-seeking: potential need and demand for infertility medical care","volume":"22","author":"Boivin","year":"2007","journal-title":"Hum Reprod"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"65","DOI":"10.1001\/jama.2021.4788","article-title":"Diagnosis and management of infertility: a 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