{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T19:52:20Z","timestamp":1791489140612,"version":"4.3.4"},"reference-count":17,"publisher":"Springer Science and Business Media LLC","license":[{"start":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T00:00:00Z","timestamp":1791417600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.springernature.com\/gp\/researchers\/text-and-data-mining"},{"start":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T00:00:00Z","timestamp":1791417600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.springernature.com\/gp\/researchers\/text-and-data-mining"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Ther Innov Regul Sci"],"DOI":"10.1007\/s43441-026-01060-5","type":"journal-article","created":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T19:12:21Z","timestamp":1791486741000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["When Randomization Assigns a Starting Strategy: An Estimand-Led Framework for Frozen Embryo Transfer Trials"],"prefix":"10.1007","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3320-4072","authenticated-orcid":false,"given":"Dang Anh","family":"Tuan","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,10,8]]},"reference":[{"key":"1060_CR1","unstructured":"International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). E9(R1) Addendum on Estimands and Sensitivity Analysis in Clinical Trials to the Guideline on Statistical Principles for Clinical Trials. https:\/\/database.ich.org\/sites\/default\/files\/E9-R1_Step4_Guideline_2019_1203.pdf. Accessed 01 May, 2026."},{"key":"1060_CR2","doi-asserted-by":"publisher","first-page":"e076316","DOI":"10.1136\/bmj-2023-076316","volume":"384","author":"BC Kahan","year":"2024","unstructured":"Kahan BC, Hindley J, Edwards M, Cro S, Morris TP. The estimands framework: a primer on the ICH E9(R1) addendum. BMJ. 2024;384:e076316. https:\/\/doi.org\/10.1136\/bmj-2023-076316.","journal-title":"BMJ"},{"key":"1060_CR3","doi-asserted-by":"publisher","first-page":"e070146","DOI":"10.1136\/bmj-2022-070146","volume":"378","author":"S Cro","year":"2022","unstructured":"Cro S, et al. Evaluating how clear the questions being investigated in randomised trials are: systematic review of estimands. BMJ. 2022;378:e070146. https:\/\/doi.org\/10.1136\/bmj-2022-070146.","journal-title":"BMJ"},{"issue":"10449","key":"1060_CR4","doi-asserted-by":"publisher","first-page":"266","DOI":"10.1016\/S0140-6736(24)00756-6","volume":"404","author":"VNA Ho","year":"2024","unstructured":"Ho VNA, et al. Livebirth rate after one frozen embryo transfer in ovulatory women starting with natural, modified natural, or artificial endometrial preparation in Viet Nam: an open-label randomised controlled trial. Lancet. 2024;404(10449):266\u201375. https:\/\/doi.org\/10.1016\/S0140-6736(24)00756-6.","journal-title":"Lancet"},{"issue":"4","key":"1060_CR5","doi-asserted-by":"publisher","first-page":"597","DOI":"10.1016\/j.fertnstert.2022.12.035","volume":"119","author":"Y Jiang","year":"2023","unstructured":"Jiang Y, et al. The effect of progesterone supplementation for luteal phase support in natural cycle frozen embryo transfer: a systematic review and meta-analysis based on randomized controlled trials. Fertil Steril. 2023;119(4):597\u2013605. https:\/\/doi.org\/10.1016\/j.fertnstert.2022.12.035. 2023\/04\/01\/.","journal-title":"Fertil Steril"},{"issue":"5","key":"1060_CR6","doi-asserted-by":"publisher","first-page":"634","DOI":"10.1093\/humupd\/dmad011","volume":"29","author":"TR Zaat","year":"2023","unstructured":"Zaat TR, Kostova EB, Korsen P, Showell MG, Mol F, van Wely M. Obstetric and neonatal outcomes after natural versus artificial cycle frozen embryo transfer and the role of luteal phase support: a systematic review and meta-analysis. Hum Reprod Update. 2023;29(5):634\u201354. https:\/\/doi.org\/10.1093\/humupd\/dmad011.","journal-title":"Hum Reprod Update"},{"key":"1060_CR7","doi-asserted-by":"publisher","DOI":"10.1007\/s10815-026-03998-9","author":"DA Tuan","year":"2026","unstructured":"Tuan DA. When similar live birth rates do not mean protocol equivalence in frozen embryo transfer. J Assist Reprod Genet. 2026. https:\/\/doi.org\/10.1007\/s10815-026-03998-9.\u00a0","journal-title":"J Assist Reprod Genet"},{"issue":"14","key":"1060_CR8","doi-asserted-by":"publisher","first-page":"1391","DOI":"10.1056\/nejmsm1605385","volume":"377","author":"MA Hern\u00e1n","year":"2017","unstructured":"Hern\u00e1n MA, Robins JM. Per-protocol analyses of pragmatic trials. N Engl J Med. 2017;377(14):1391\u20138. https:\/\/doi.org\/10.1056\/nejmsm1605385","journal-title":"N Engl J Med"},{"key":"1060_CR9","doi-asserted-by":"publisher","unstructured":"Dancet EAF, Nelen WLDM, Sermeus W, De Leeuw L, Kremer JAM. and T. M. D\u2019Hooghe, The patients\u2019 perspective on fertility care: a systematic review, Human Reproduction Update. 2010;16(5):467\u2013487. https:\/\/doi.org\/10.1093\/humupd\/dmq004.","DOI":"10.1093\/humupd\/dmq004"},{"issue":"12","key":"1060_CR10","doi-asserted-by":"publisher","first-page":"2703","DOI":"10.1093\/humrep\/dev263","volume":"30","author":"D Maheshwari","year":"2015","unstructured":"Maheshwari D, McLernon, Bhattacharya S. Cumulative live birth rate: time for a consensus? Hum Reprod. 2015;30(12):2703\u20137. https:\/\/doi.org\/10.1093\/humrep\/dev263.","journal-title":"Hum Reprod"},{"issue":"8","key":"1060_CR11","doi-asserted-by":"publisher","first-page":"1732","DOI":"10.1093\/humrep\/deaa138","volume":"35","author":"SK Sunkara","year":"2020","unstructured":"Sunkara SK, Zheng W, D\u2019Hooghe T, Longobardi S, Boivin J. Time as an outcome measure in fertility-related clinical studies: long-awaited. Hum Reprod. 2020;35(8):1732\u20139. https:\/\/doi.org\/10.1093\/humrep\/deaa138.","journal-title":"Hum Reprod"},{"key":"1060_CR12","doi-asserted-by":"publisher","unstructured":"Wang Z, Cantineau AEP, Hoek A, van Eekelen R, Mol BW, Wang R. Live birth is not the only relevant outcome in research assessing assisted reproductive technology. Best Pract Res Clin Obstet Gynecol. 2023;86:102306. https:\/\/doi.org\/10.1016\/j.bpobgyn.2022.102306.","DOI":"10.1016\/j.bpobgyn.2022.102306"},{"issue":"3","key":"1060_CR13","doi-asserted-by":"publisher","first-page":"341","DOI":"10.1093\/humupd\/dmae001","volume":"30","author":"F von Estorff","year":"2024","unstructured":"von Estorff F, Mochtar MH, Lehmann V, van Wely M. Driving factors in treatment decision-making of patients seeking medical assistance for infertility: a systematic review. Hum Reprod Update. 2024;30(3):341\u201354. https:\/\/doi.org\/10.1093\/humupd\/dmae001.","journal-title":"Hum Reprod Update"},{"key":"1060_CR14","doi-asserted-by":"publisher","first-page":"e087045","DOI":"10.1136\/bmj-2025-087045","volume":"392","author":"D Wei","year":"2026","unstructured":"Wei D, et al. Natural ovulation versus programmed regimens before frozen embryo transfer in ovulatory women: multicentre, randomised clinical trial. BMJ. 2026;392:e087045. https:\/\/doi.org\/10.1136\/bmj-2025-087045.","journal-title":"BMJ"},{"key":"1060_CR15","doi-asserted-by":"publisher","unstructured":"von Versen-H\u00f6ynck F et al. Absent or Excessive Corpus Luteum Number Is Associated With Altered Maternal Vascular Health in Early Pregnancy, Hypertension. 2019;73(3):680\u2013690. https:\/\/doi.org\/10.1161\/HYPERTENSIONAHA.118.12046.","DOI":"10.1161\/HYPERTENSIONAHA.118.12046"},{"key":"1060_CR16","doi-asserted-by":"publisher","first-page":"e073725","DOI":"10.1136\/bmj-2022-073725","volume":"381","author":"DR Junqueira","year":"2023","unstructured":"Junqueira DR, et al. CONSORT Harms 2022 statement, explanation, and elaboration: updated guideline for the reporting of harms in randomised trials. BMJ. 2023;381:e073725. https:\/\/doi.org\/10.1136\/bmj-2022-073725.","journal-title":"BMJ"},{"issue":"11","key":"1060_CR17","doi-asserted-by":"publisher","first-page":"2234","DOI":"10.1093\/humrep\/dex285","volume":"32","author":"S Mackens","year":"2017","unstructured":"Mackens S, et al. Frozen embryo transfer: a review on the optimal endometrial preparation and timing. Hum Reprod. 2017;32(11):2234\u201342. https:\/\/doi.org\/10.1093\/humrep\/dex285.","journal-title":"Hum Reprod"}],"container-title":["Therapeutic Innovation & Regulatory Science"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s43441-026-01060-5.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s43441-026-01060-5","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s43441-026-01060-5.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T19:12:22Z","timestamp":1791486742000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s43441-026-01060-5"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,10,8]]},"references-count":17,"alternative-id":["1060"],"URL":"https:\/\/doi.org\/10.1007\/s43441-026-01060-5","relation":{},"ISSN":["2168-4790","2168-4804"],"issn-type":[{"value":"2168-4790","type":"print"},{"value":"2168-4804","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,10,8]]},"assertion":[{"value":"1 May 2026","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"1 October 2026","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"8 October 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"This article does not involve any studies conducted by the author that included human participants.","order":1,"name":"Ethics","label":"Ethics Approval and Consent to Participate","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare no competing interests.","order":2,"name":"Ethics","label":"Competing Interests","group":{"name":"EthicsHeading","label":"Declarations"}}]}}