{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,4]],"date-time":"2026-07-04T17:20:28Z","timestamp":1783185628292,"version":"3.54.6"},"reference-count":37,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,5,24]],"date-time":"2025-05-24T00:00:00Z","timestamp":1748044800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background: An univocal definition for a lack of glucose peak during the oral glucose tolerance test in pregnancy (flat curve) has never been agreed upon. Thus, the aim of this study was to provide a definition for the flat 75 g oral glucose tolerance test (OGTT) and to assess its clinical significance. Methods: A retrospective cohort study, where 8.810 pregnant singleton women were evaluated at the time of a 75 g OGTT between 240 and 286 weeks for the universal screening of gestational diabetes (GDM). The 75 g OGTT was considered flat when the difference between peak and fasting glucose concentrations was \u226430 mg\/dL. A total of 953 (10.8%) women were diagnosed as having GDM, while 7.857 (89.2%) had normal glucose tolerance (NGT); 2791 women with normal glucose tolerance (35.5%) had a FLAT curve and 5066 (64.5%) had a concentration difference &gt; 30 mg\/dL (NGT). In all groups, we evaluated maternal characteristics and perinatal outcome. Results: Women with a FLAT curve were younger, taller, thinner, and their pre-pregnancy body mass index was lower than the other groups (all p &lt; 0.001). The rate of obesity was also lower (p &lt; 0.01). The vaginal delivery rate was higher than in NGT (80.4% vs. 77.8%; p &lt; 0.01) and women with GDM (73.0%; p &lt; 0.001) and that of primary cesarean lower than in NGT (11.9% vs. 14.8%; p &lt; 0.001) and women with GDM (18.2%; p &lt; 0.001). Between women with a FLAT and NGT OGTT curve, there was no significant difference for birthweight &lt; 10th percentile (6.9% vs. 6.2%; p = 0.2), though the proportion of birthweight &gt; 90th was lower (8% vs. 10%; p &lt; 0.01). Conclusions: A 75 g flat OGTT as defined does not represent an abnormal maternal phenotype nor portend an adverse perinatal outcome.<\/jats:p>","DOI":"10.3390\/nu17111785","type":"journal-article","created":{"date-parts":[[2025,5,25]],"date-time":"2025-05-25T20:16:22Z","timestamp":1748204182000},"page":"1785","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["The Lack of a Glucose Peak During the Oral Glucose Tolerance Test in Pregnancy: What Does It Portend for Perinatal Outcomes?"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6295-1854","authenticated-orcid":false,"given":"Anna Maria","family":"Marconi","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynecology, San Paolo Hospital Medical School, ASST Santi Paolo e Carlo, Via A di Rudin\u00ec 8, 20142 Milan, Italy"},{"name":"Department of Health Sciences, University of Milan, 20124 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-8669-9985","authenticated-orcid":false,"given":"Nikita","family":"Alfieri","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, San Paolo Hospital Medical School, ASST Santi Paolo e Carlo, Via A di Rudin\u00ec 8, 20142 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4062-1114","authenticated-orcid":false,"given":"Emanuele","family":"Garzia","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, San Paolo Hospital Medical School, ASST Santi Paolo e Carlo, Via A di Rudin\u00ec 8, 20142 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0716-5663","authenticated-orcid":false,"given":"Stefano","family":"Terzoni","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences for Health, University of Milan, 20124 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1837-0806","authenticated-orcid":false,"given":"Stefano","family":"Manodoro","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, San Paolo Hospital Medical School, ASST Santi Paolo e Carlo, Via A di Rudin\u00ec 8, 20142 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3291-3034","authenticated-orcid":false,"given":"Patrick M.","family":"Catalano","sequence":"additional","affiliation":[{"name":"Reproductive Endocrinology Unit, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA 02115, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"ACOG (2018). 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