{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,3]],"date-time":"2026-05-03T23:52:20Z","timestamp":1777852340526,"version":"3.51.4"},"reference-count":36,"publisher":"SAGE Publications","issue":"1","license":[{"start":{"date-parts":[[2026,2,1]],"date-time":"2026-02-01T00:00:00Z","timestamp":1769904000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"funder":[{"name":"the Science and Technology Project of Sichuan Provincial Health Commission","award":["Grant No. 21PJ134"],"award-info":[{"award-number":["Grant No. 21PJ134"]}]}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["J Hum Lact"],"published-print":{"date-parts":[[2026,2]]},"abstract":"<jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>While prior studies have established associations between specific factors and delayed onset of Lactogenesis II, critical gaps remain in understanding how the timing of lactogenesis initiation dynamically affects macronutrient levels within 72\u2009hours postpartum, and whether modifiable factors alter these relationships.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Research Aims:<\/jats:title>\n                    <jats:p>To validate known risk factors for delayed lactogenesis in a Chinese population; characterize time-specific macronutrient changes; and evaluate how modifiable factors (e.g., gestational diabetes mellitus) influence human milk composition.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>In this prospective cohort study, 360 participants were interviewed during the first 24\u2009hours postpartum in China. At 24-hour intervals, the onset of lactogenesis was determined based on maternal perception. The participants were divided into delayed onset of lactogenesis and onset of lactogenesis groups. Human milk samples were collected at 24, 48, and 72\u2009hours postpartum, and their macronutrient content (lactose, fat, and protein) was determined using a human milk analyzer.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>\n                      Approximately 23.6% (\n                      <jats:italic toggle=\"yes\">n<\/jats:italic>\n                      = 85) of participants experienced delayed lactogenesis, which was significantly associated with gestational diabetes mellitus, Cesarean delivery, and pre-pregnancy body mass index \u2265 25.0\u2009kg\/m\n                      <jats:sup>2<\/jats:sup>\n                      (odds ratio [95% confidence interval] = 2.32 [1.20, 4.50], 2.02 [1.20, 3.41], and 2.75 [1.23, 6.18], respectively).\n                    <\/jats:p>\n                    <jats:p>\n                      Lactose concentration was significantly lower in the delayed onset of lactogenesis group at 24\u2009hours: Wald \u03c7\u00b2(1) = 23.71,\n                      <jats:italic toggle=\"yes\">p &lt;<\/jats:italic>\n                      0.001, and 48\u2009hours: Wald \u03c7\u00b2(1) = 8.26,\n                      <jats:italic toggle=\"yes\">p<\/jats:italic>\n                      = 0.04, as well as in those with gestational diabetes at 24\u2009hours postpartum: Wald \u03c7\u00b2(1) = 9.60,\n                      <jats:italic toggle=\"yes\">p<\/jats:italic>\n                      = 0.002.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion:<\/jats:title>\n                    <jats:p>Beyond confirming known risk factors for delayed lactogenesis in China, our identification of time-dependent lactose deficiency highlights the need for lactose concentration monitoring within the first 48\u2009hours postpartum.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1177\/08903344251394750","type":"journal-article","created":{"date-parts":[[2026,2,8]],"date-time":"2026-02-08T09:30:23Z","timestamp":1770543023000},"page":"165-176","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":0,"title":["Changes in Human Milk Macronutrients and Risk Factors for Delayed Lactogenesis: A Prospective Cohort Study"],"prefix":"10.1177","volume":"42","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7356-2827","authenticated-orcid":false,"given":"Yuan","family":"Deng","sequence":"first","affiliation":[{"name":"University of Electronic Science and Technology of China, Chengdu, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mei-Jun","family":"Guan","sequence":"additional","affiliation":[{"name":"University of Electronic Science and Technology of China, Chengdu, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shao-Chuan","family":"Chen","sequence":"additional","affiliation":[{"name":"University of Electronic Science and Technology of China, Chengdu, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xin","family":"Wang","sequence":"additional","affiliation":[{"name":"University of Electronic Science and Technology of China, Chengdu, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ying","family":"Wang","sequence":"additional","affiliation":[{"name":"University of Electronic Science and Technology of China, Chengdu, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pei-Yu","family":"He","sequence":"additional","affiliation":[{"name":"University of Electronic Science and Technology of China, Chengdu, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[2026,2,8]]},"reference":[{"key":"e_1_3_2_2_1","doi-asserted-by":"crossref","unstructured":"American Diabetes Association. 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