{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T06:56:15Z","timestamp":1790751375344,"version":"4.1.0"},"reference-count":23,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T00:00:00Z","timestamp":1790726400000},"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. Reprod. Health"],"abstract":"<jats:sec>\n                    <jats:title>Research question<\/jats:title>\n                    <jats:p>Can follitropin delta be used in a conventional regimen (15\u2005\u00b5g\/day starting dose) without compromising efficacy and safety in patients seeking fertility treatment in Spain?<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>\n                      This was an exploratory\n                      <jats:italic>post hoc<\/jats:italic>\n                      analysis of the ADAPT-1 randomized controlled trial. Participants, 18\u201340 years, enrolled at specialist reproductive centers in Spain in this accessor-blinded, multicenter trial assessing efficacy and safety of conventional follitropin delta 15\u2005\u03bcg\/day and follitropin alfa 225\u2005IU\/day for ovarian stimulation. The primary endpoint was the number of oocytes retrieved. During the follow-up period, clinical pregnancies from the first fresh or frozen transfer within 3 months of the start of stimulation, and ovarian hyperstimulation syndrome (OHSS) rates were assessed. All cycles used a gonadotropin-releasing hormone (GnRH) antagonist protocol.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      A total of 132 patients were randomized (10-AUG-2022 to 11-MAR-2024): follitropin delta group,\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u200985; follitropin alfa group,\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u200947. The adjusted mean number of oocytes retrieved was 10.6 and 11.0 for each group, respectively [difference: \u22120.3 (95% CI: \u22122.4; 1.7)]. Adjusted clinical pregnancy rates per started cycle were 34.8% and 32.0%, respectively [difference: 2.8% (95% CI: \u221214.3; 20.0)]. Adverse events were reported for 28.2% and 42.6% of participants, respectively, with the most common adverse events being headache [10.6% (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u20099) and 8.5% (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u20094)], pelvic discomfort [4.7% (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u20094) and 4.3% (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u20092)], dysmenorrhea [0% and 6.4% (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u20093)], and early OHSS [1.2% (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u20091) and 4.3% (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u20092)].\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Our exploratory analysis shows that a higher starting dose of follitropin delta 15\u2005\u00b5g\/day in a conventional regimen can be successfully used in appropriately selected infertile patients, resulting in a good average oocyte yield without compromising first-transfer clinical pregnancy rates and while maintaining a low incidence of early OHSS.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/frph.2026.1927550","type":"journal-article","created":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T06:06:18Z","timestamp":1790748378000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Comparative outcomes of conventional follitropin delta 15\u2005\u00b5g\/day versus follitropin alfa 225\u2005IU\/day for ovarian stimulation: results from an exploratory post hoc analysis of Spanish participants from the ADAPT-1 randomized controlled trial"],"prefix":"10.3389","volume":"8","author":[{"given":"Marta","family":"Garc\u00eda S\u00e1nchez","sequence":"first","affiliation":[{"name":"IVIRMA Global Research Alliance, IVIRMA","place":["M\u00e1laga, Spain"]},{"name":"Hospital Quironsalud M\u00e1laga","place":["M\u00e1laga, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Bernabeu","sequence":"additional","affiliation":[{"name":"Instituto Bernabeu Alicante, Albufereta","place":["Alicante, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana","family":"Hern\u00e1ndez Cesteros","sequence":"additional","affiliation":[{"name":"Vida Recoletas Salud","place":["Valladolid, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Blasco Gast\u00f3n","sequence":"additional","affiliation":[{"name":"Ginefiv","place":["Madrid, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sofia","family":"Ortega Ricondo","sequence":"additional","affiliation":[{"name":"Hospital Universitario Principe De Asturias","place":["Madrid, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gemma","family":"Castill\u00f3n","sequence":"additional","affiliation":[{"name":"IVI","place":["Barcelona, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcos","family":"Ferrando Serrano","sequence":"additional","affiliation":[{"name":"IVIRMA Global Research Alliance, IVIRMA","place":["Bilbao, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Signe","family":"M\u00f8gelmose","sequence":"additional","affiliation":[{"name":"Global Biometrics, Ferring Pharmaceuticals","place":["Kastrup, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Enrica","family":"Gravotta","sequence":"additional","affiliation":[{"name":"Global Research and Medical, Ferring Pharmaceuticals","place":["Kastrup, 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