{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T13:28:41Z","timestamp":1786973321278,"version":"build-2736575974"},"reference-count":21,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T00:00:00Z","timestamp":1781049600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T00:00:00Z","timestamp":1786924800000},"content-version":"vor","delay-in-days":68,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Manipal Academy of Higher Education, Manipal"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Arch Gynecol Obstet"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>To examine the association between follicular output rate (FORT) and embryological and clinical outcomes, including live birth rate, in patients undergoing in vitro fertilization (IVF).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This prospective cohort study enrolled 166 patients undergoing IVF between October 2023 and January 2025. FORT was calculated as the ratio of pre-ovulatory follicles (16\u201324\u00a0mm) on trigger day to baseline antral follicle count (AFC; 3\u20139\u00a0mm), multiplied by 100. Patients were stratified into low, medium, and high FORT tertiles, and FORT was also evaluated as a continuous variable in multivariable logistic regression. An exploratory receiver operating characteristic (ROC) analysis was performed to assess discriminatory performance and to identify a data-derived reference threshold. All analyses were conducted separately for non-PCOS and PCOS cohorts.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>In non-PCOS patients (n\u2009=\u2009136), the number of oocytes retrieved, mature oocytes, and good-quality embryos differed significantly across FORT tertiles (all p\u2009&lt;\u20090.05). Clinical pregnancy rates were 14.9%, 27.8%, and 37.2% in the low, medium, and high FORT groups respectively (p\u2009=\u20090.045), with corresponding differences in live birth rates (p\u2009=\u20090.049). On multivariable analysis, FORT (OR 1.04; 95% CI 1.002\u20131.079; p\u2009=\u20090.039) and the number of available embryos (OR 1.35; 95% CI 1.082\u20131.676; p\u2009=\u20090.008) remained independently associated with clinical pregnancy. Exploratory ROC analysis yielded an AUC of 0.607 (95% CI 0.52\u20130.69). A data-derived reference threshold of FORT at 64.2% was associated with higher clinical pregnancy rates compared with lower FORT values (40.9% vs. 23.3%; p\u2009=\u20090.030; OR 2.27, 95% CI 1.14\u20134.55). No significant associations were observed in the PCOS subgroup, though this analysis was limited by small sample size (n\u2009=\u200930).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>FORT is significantly associated with embryological and clinical pregnancy outcomes, including live birth, in non-PCOS IVF patients. As a cycle-specific functional measure of follicular responsiveness, FORT may complement static ovarian reserve markers for counselling and outcome stratification. FORT values in the higher range (approximately\u2009\u2265\u200965%) were associated with improved clinical pregnancy rates, but the limited discriminatory performance of the ROC analysis underscores the need for external prospective validation of this cutoff before any clinical implementation.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00404-026-08487-z","type":"journal-article","created":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T14:26:10Z","timestamp":1781101570000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Evaluating the role of follicular output rate in clinical and embryological outcomes in IVF: a prospective study"],"prefix":"10.1007","volume":"313","author":[{"given":"Arshiya","family":"Firdaus","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anjali S.","family":"Mundkur","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vidyashree G.","family":"Poojari","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pratap","family":"Kumar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Srisailesh","family":"Vitthala","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Prashanth K.","family":"Adiga","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,10]]},"reference":[{"issue":"1","key":"8487_CR1","doi-asserted-by":"publisher","DOI":"10.1186\/s13643-024-02684-0","volume":"13","author":"F Salemi","year":"2024","unstructured":"Salemi F, Jambarsang S, Kheirkhah A et al (2024) The best ovarian reserve marker to predict ovarian response following controlled ovarian hyperstimulation: a systematic review and meta-analysis. 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