{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T16:51:16Z","timestamp":1791478276552,"version":"4.3.4"},"reference-count":20,"publisher":"Walter de Gruyter GmbH","issue":"10","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,26]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec id=\"j_jpem-2026-0309_abs_001\">\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>Data on menstrual cycle\u2013related metabolic variability in adolescents with type 1 diabetes (T1D) using automated insulin delivery (AID) systems are scarce. We aimed to quantify cycle-dependent differences in insulin requirements and glycemic outcomes in this population.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_jpem-2026-0309_abs_002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In this retrospective observational cohort study, adolescents with T1D aged 12.0\u201317.9\u00a0years who were at least 1\u00a0year postmenarche and had used AID for\u00a0\u22656\u00a0months were included. Menstrual cycles were tracked using smartphone applications, and nine complete cycles per participant were analyzed. Insulin delivery and continuous glucose monitoring data were extracted from Glooko. Outcomes included total daily insulin dose (TDD), time in range (TIR), time above range (TAR), time below range (TBR), mean glucose, glucose coefficient of variation (CV), and recorded carbohydrate intake. Linear mixed-effects models were\u00a0used.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_jpem-2026-0309_abs_003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Fifty-one adolescents contributed 459 menstrual cycles. Mean age was 14.7\u00a0\u00b1\u00a01.8 years, and median HbA\n                      <jats:sub>1c<\/jats:sub>\n                      was 7.2\u202f% (interquartile range 6.8\u20137.5\u202f%). TDD was higher during the luteal than the follicular phase (1.05 vs. 0.95\u202fU\/kg\/day; mean difference +0.10\u202fU\/kg\/day, 95\u202f% CI 0.05\u20130.15; p&lt;0.001). The luteal phase was associated with reduced TIR (\u22126.3\u202f%, p=0.001), increased TAR (+5.5\u202f%, p=0.01), higher mean glucose (+12.5\u202fmg\/dL, p=0.03), and higher CV (39.4 vs. 35.0\u202f%, p=0.03). TBR and carbohydrate intake did not differ significantly.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"j_jpem-2026-0309_abs_004\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In adolescents with T1D who menstruate and use AID systems, insulin requirements and glycemic control vary across the menstrual cycle, with increased insulin demand and hyperglycemia during the luteal phase. These findings highlight clinically relevant cycle-related metabolic variability despite the use of\u00a0AID.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1515\/jpem-2026-0309","type":"journal-article","created":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T22:55:30Z","timestamp":1787957730000},"page":"990-999","source":"Crossref","is-referenced-by-count":0,"title":["Menstrual cycle\u2013related variations in insulin requirements and glycemic control during automated insulin delivery in adolescents with type 1 diabetes"],"prefix":"10.1515","volume":"39","author":[{"given":"Nora","family":"Struckmeyer","sequence":"first","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"},{"name":"Gynpraxis Hannover , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Landsberg","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8051-5562","authenticated-orcid":false,"given":"Torben","family":"Biester","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rodica Mia","family":"Doelle","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ann-Kristin","family":"Frerking","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kerstin","family":"Kapitzke","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Niclas","family":"Knottnerus-Meyer","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mareike","family":"Niemeyer","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-5249-9986","authenticated-orcid":false,"given":"Rebecca","family":"Toenne","sequence":"additional","affiliation":[{"name":"Betreuungsnetz, Paediatric Serious Illness Care Network , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thekla von dem","family":"Berge","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zlata","family":"Vukadinovic-Nikolic","sequence":"additional","affiliation":[{"name":"Gynpraxis Hannover , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-8663-3723","authenticated-orcid":false,"given":"Jantje","family":"Weiskorn","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olga","family":"Kordonouri","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1170-6706","authenticated-orcid":false,"given":"Felix","family":"Reschke","sequence":"additional","affiliation":[{"name":"Centre for Diabetology and Endocrinology, Children`s Hospital AUF DER BULT , Hannover , Germany"},{"name":"Betreuungsnetz, Paediatric Serious Illness Care Network , Hannover , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"374","published-online":{"date-parts":[[2026,8,31]]},"reference":[{"key":"2026100815572198147_j_jpem-2026-0309_ref_001","doi-asserted-by":"crossref","unstructured":"Gamarra, E, Trimboli, P. 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J\u00a0Diabetes Sci Technol 2023;17:1304\u201316. https:\/\/doi.org\/10.1177\/19322968221080199.","DOI":"10.1177\/19322968221080199"},{"key":"2026100815572198147_j_jpem-2026-0309_ref_004","doi-asserted-by":"crossref","unstructured":"Schieren, A, Koch, S, Pecht, T, Simon, MC. Impact of physiological fluctuations of sex hormones during the menstrual cycle on glucose metabolism and the gut microbiota. Exp Clin Endocrinol Diabetes 2024;132:267\u201378. https:\/\/doi.org\/10.1055\/a-2273-5602.","DOI":"10.1055\/a-2273-5602"},{"key":"2026100815572198147_j_jpem-2026-0309_ref_005","doi-asserted-by":"crossref","unstructured":"Bruns, CM, Kemnitz, JW. Sex hormones, insulin sensitivity, and diabetes mellitus. ILAR J 2004;45:160\u20139. https:\/\/doi.org\/10.1093\/ilar.45.2.160.","DOI":"10.1093\/ilar.45.2.160"},{"key":"2026100815572198147_j_jpem-2026-0309_ref_006","doi-asserted-by":"crossref","unstructured":"\u0160umn\u00edk, Z, Pr\u016fhov\u00e1, \u0160. Diabetes in children and adolescents. 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Nat Metab 2023;5:1475\u201382. https:\/\/doi.org\/10.1038\/s42255-023-00869-w.","DOI":"10.1038\/s42255-023-00869-w"}],"container-title":["Journal of Pediatric Endocrinology and Metabolism"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.degruyterbrill.com\/document\/doi\/10.1515\/jpem-2026-0309\/xml","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.degruyterbrill.com\/document\/doi\/10.1515\/jpem-2026-0309\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T15:58:23Z","timestamp":1791475103000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.degruyterbrill.com\/document\/doi\/10.1515\/jpem-2026-0309\/html"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,31]]},"references-count":20,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2026,7,27]]},"published-print":{"date-parts":[[2026,10,26]]}},"alternative-id":["10.1515\/jpem-2026-0309"],"URL":"https:\/\/doi.org\/10.1515\/jpem-2026-0309","relation":{},"ISSN":["0334-018X","2191-0251"],"issn-type":[{"value":"0334-018X","type":"print"},{"value":"2191-0251","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,31]]}}}