{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T03:07:53Z","timestamp":1784257673325,"version":"3.55.0"},"reference-count":37,"publisher":"Wiley","issue":"2","license":[{"start":{"date-parts":[[2018,10,24]],"date-time":"2018-10-24T00:00:00Z","timestamp":1540339200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"funder":[{"name":"European Union, Interreg V \u00d6KS"}],"content-domain":{"domain":["obgyn.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["BJOG"],"published-print":{"date-parts":[[2019,1]]},"abstract":"<jats:sec><jats:title>Objective<\/jats:title><jats:p>To assess academic performance in singletons aged 15\u201316\u00a0years conceived after frozen embryo transfer (<jats:styled-content style=\"fixed-case\">FET<\/jats:styled-content>) compared with singletons born after fresh embryo transfer (<jats:styled-content style=\"fixed-case\">ET<\/jats:styled-content>) in Danish cohorts born from 1995 to 2001.<\/jats:p><\/jats:sec><jats:sec><jats:title>Design<\/jats:title><jats:p>Danish national registry\u2010based cohort study.<\/jats:p><\/jats:sec><jats:sec><jats:title>Setting<\/jats:title><jats:p>Danish national registries.<\/jats:p><\/jats:sec><jats:sec><jats:title>Population<\/jats:title><jats:p>All 6495 singletons conceived after assisted reproductive technology (<jats:styled-content style=\"fixed-case\">ART<\/jats:styled-content>) treatment in Denmark from 1995 to 2001 [<jats:styled-content style=\"fixed-case\">FET<\/jats:styled-content> (<jats:italic>n<\/jats:italic>)\u00a0=\u00a0423; fresh <jats:styled-content style=\"fixed-case\">ET<\/jats:styled-content> (<jats:italic>n<\/jats:italic>)\u00a0=\u00a06072].<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>Mean test scores on a national standardised and international comparable grading\u2010scale. Comparisons of test score were first made in univariate analysis (Model 1) and secondly in a multivariate linear model (Model 2) adjusting for relevant reproductive and socio\u2010demographic covariates such as the occupational and educational level of the parents. Sensitivity analyses on FET\u2010IVF (in vitro fertilisation) versus fresh ET\u2010IVF and FET\u2010ICSI (intracytoplasmic sperm injection) versus fresh ET\u2010ICSI were made. Linear mixed models were used to account for the correlation in test scores of siblings for continuous outcome.<\/jats:p><\/jats:sec><jats:sec><jats:title>Main outcome measures<\/jats:title><jats:p>Mean overall test score and test score in Danish, mathematics, English, and physics\/chemistry.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>Crude and adjusted mean test scores were similar for adolescents conceived after <jats:styled-content style=\"fixed-case\">FET<\/jats:styled-content> compared with fresh <jats:styled-content style=\"fixed-case\">ET<\/jats:styled-content>. The crude mean difference was +0.11 (95% <jats:styled-content style=\"fixed-case\">CI<\/jats:styled-content> \u22120.11; 0.34), and the adjusted mean difference was +0.12 (95% <jats:styled-content style=\"fixed-case\">CI<\/jats:styled-content> \u22120.09; 0.34).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>Adolescents conceived after <jats:styled-content style=\"fixed-case\">FET<\/jats:styled-content> had similar academic performance at 15\u201316 of years of age compared with children conceived after fresh <jats:styled-content style=\"fixed-case\">ET<\/jats:styled-content>.<\/jats:p><\/jats:sec><jats:sec><jats:title>Tweetable abstract<\/jats:title><jats:p>Using frozen embryos in fertility treatment does not affect school performance in Danish adolescents aged 15\u201316 years.<\/jats:p><\/jats:sec>","DOI":"10.1111\/1471-0528.15484","type":"journal-article","created":{"date-parts":[[2018,10,2]],"date-time":"2018-10-02T00:51:03Z","timestamp":1538441463000},"page":"261-269","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Academic performance in adolescents aged 15\u201316 years born after frozen embryo transfer compared with fresh embryo transfer: a nationwide registry\u2010based cohort study"],"prefix":"10.1111","volume":"126","author":[{"given":"AL","family":"Spangmose","sequence":"first","affiliation":[{"name":"Fertility Clinic Department of Obstetrics and Gynecology Copenhagen University Hospital Hvidovre, Copenhagen Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"SS","family":"Malchau","sequence":"additional","affiliation":[{"name":"Fertility Clinic Department of Obstetrics and Gynecology Copenhagen University Hospital Hvidovre, Copenhagen Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"AA","family":"Henningsen","sequence":"additional","affiliation":[{"name":"The Fertility Clinic Copenhagen University Hospital Rigshospitalet Copenhagen Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"JL","family":"Forman","sequence":"additional","affiliation":[{"name":"Section\u00a0of Biostatistics Department of Public Health University of Copenhagen Copenhagen Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S","family":"Rasmussen","sequence":"additional","affiliation":[{"name":"The Fertility Clinic Copenhagen University Hospital Rigshospitalet Copenhagen Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A","family":"Loft","sequence":"additional","affiliation":[{"name":"The Fertility Clinic Copenhagen University Hospital Rigshospitalet Copenhagen Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"L","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Department of Public Health University of Copenhagen Copenhagen Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A","family":"Pinborg","sequence":"additional","affiliation":[{"name":"The Fertility Clinic Copenhagen University Hospital Rigshospitalet Copenhagen Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2018,10,24]]},"reference":[{"key":"e_1_2_6_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0015-0282(16)48029-5"},{"key":"e_1_2_6_3_1","doi-asserted-by":"publisher","DOI":"10.1093\/humrep\/dey242"},{"key":"e_1_2_6_4_1","unstructured":"FertilitetsselskabD.Annual report 2017. 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