{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T20:08:31Z","timestamp":1762200511440,"version":"build-2065373602"},"reference-count":54,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T00:00:00Z","timestamp":1761868800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Italian Ministry of University and Research","award":["202279JKW5"],"award-info":[{"award-number":["202279JKW5"]}]},{"DOI":"10.13039\/501100003196","name":"Italian Ministry of Health","doi-asserted-by":"publisher","award":["WFR PNRR-MCNT2-2023-12377884"],"award-info":[{"award-number":["WFR PNRR-MCNT2-2023-12377884"]}],"id":[{"id":"10.13039\/501100003196","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background\/Objectives: Prenatal environmental exposure may influence disease risk later in life. Previous studies suggest that season or month of birth affects susceptibility to various conditions, including type 2 diabetes. We aimed to evaluate whether birth timing is associated with gestational diabetes mellitus (GDM). Methods: We conducted a retrospective cohort study of 8744 pregnant women screened for GDM between August 2011 and March 2020, according to Italian Ministry of Health guidelines. Only women born and raised in Calabria were included. Logistic regression and Cosinor analysis were performed. Results: Birth distribution peaked in January (30.7%) and was lowest in October (22.3%). Being born in January was associated with higher GDM [OR 1.287 (1.090\u20131.520), p = 0.003], whereas October and June births were protective [OR 0.800 (0.672\u20130.954), p = 0.013, and OR 0.818 (0.682\u20130.980), p = 0.030, respectively]. Birth in cold months increased GDM risk [OR 1.196 (1.080\u20131.325), p &lt; 0.001], while birth in warm months was protective [OR 0.834 (0.758\u20131.917), p &lt; 0.001]. Cosinor analysis of fasting glucose at OGTT confirmed significant seasonal periodicity (p = 0.0053). Conclusions: Season and month of birth are associated with GDM risk, cold-month births predisposing and warm-month births protecting. These findings suggest that early-life seasonal factors, potentially including maternal hyperglycemia during pregnancy, may influence future GDM risk.<\/jats:p>","DOI":"10.3390\/jcm14217756","type":"journal-article","created":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T19:30:27Z","timestamp":1762198227000},"page":"7756","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Gestational Diabetes Risk May Vary Depending on Birth Month"],"prefix":"10.3390","volume":"14","author":[{"given":"Eusebio","family":"Chiefari","sequence":"first","affiliation":[{"name":"Department of Health Sciences, University \u201cMagna Gr\u00e6cia\u201d of Catanzaro, 88100 Catanzaro, Italy"},{"name":"Operative Unit of Endocrinology, \u201cR. Dulbecco\u201d University Hospital, 88100 Catanzaro, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6427-7186","authenticated-orcid":false,"given":"Maria","family":"Mirabelli","sequence":"additional","affiliation":[{"name":"Department of Health Sciences, University \u201cMagna Gr\u00e6cia\u201d of Catanzaro, 88100 Catanzaro, Italy"},{"name":"Operative Unit of Endocrinology, \u201cR. Dulbecco\u201d University Hospital, 88100 Catanzaro, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Livia Cornelia","family":"Chiefari","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Padova Medical School, 35129 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesco S.","family":"Brunetti","sequence":"additional","affiliation":[{"name":"Department of Health Sciences, University \u201cMagna Gr\u00e6cia\u201d of Catanzaro, 88100 Catanzaro, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stefania","family":"Giuliano","sequence":"additional","affiliation":[{"name":"Operative Unit of Endocrinology, \u201cR. Dulbecco\u201d University Hospital, 88100 Catanzaro, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9536-5736","authenticated-orcid":false,"given":"Daniela P.","family":"Foti","sequence":"additional","affiliation":[{"name":"Department of Experimental and Clinical Medicine, University \u201cMagna Gr\u00e6cia\u201d of Catanzaro, 88100 Catanzaro, Italy"},{"name":"Operative Unit of Clinical Pathology, \u201cRenato Dulbecco\u201d Hospital, 88100 Catanzaro, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1533-8779","authenticated-orcid":false,"given":"Antonio","family":"Brunetti","sequence":"additional","affiliation":[{"name":"Department of Health Sciences, University \u201cMagna Gr\u00e6cia\u201d of Catanzaro, 88100 Catanzaro, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"American Diabetes Association Professional Practice Committee (2025). 2. 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