{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T01:51:43Z","timestamp":1785894703236,"version":"3.56.0"},"reference-count":47,"publisher":"Oxford University Press (OUP)","issue":"8","license":[{"start":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T00:00:00Z","timestamp":1778630400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"funder":[{"name":"Eunice Kennedy Shriver National Institute of Child Health & Human Development, National Institutes of Health","award":["R01HD107753"],"award-info":[{"award-number":["R01HD107753"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,5]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Empirical evidence on COVID-19 vaccination and lactation-related outcomes remains limited. We used electronic health record data from 4 US healthcare systems to assess the association between COVID-19 vaccination and milk feeding outcomes. We included pregnant persons with a live birth between December 2020 and September 2022 with infant linkage. We assessed 2 COVID-19 vaccination exposure windows\u2014during pregnancy (\u226520\u00a0weeks gestation vs no vaccination during pregnancy) or postpartum (&amp;lt;7\u00a0months after delivery vs none). We estimated adjusted prevalence ratios (aPR) for COVID-19 vaccination during pregnancy and human milk feeding non-initiation and discontinuation, and we estimated adjusted hazard ratios (aHR) for postpartum COVID-19 vaccination and human milk feeding discontinuation. In the study population used to assess pregnancy exposure (N\u00a0=\u00a010\u2009757), 4.2% of birthing parents did not initiate human milk feeding. Non-initiation did not differ by vaccination during pregnancy (aPR\u00a0=\u00a00.99; 95% CI, 0.98-1.01). Antenatal vaccination was not associated with human milk feeding discontinuation at 2 and 6\u00a0months after delivery. In the study population used to assess postpartum exposure (N\u00a0=\u00a017\u2009161), human milk feeding discontinuation did not differ by postpartum vaccination (aHR\u00a0=\u00a01.03; 95% CI, 0.95-1.11). COVID-19 vaccination in pregnancy and postpartum were not associated with human milk feeding discontinuation.<\/jats:p>","DOI":"10.1093\/aje\/kwag105","type":"journal-article","created":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T12:11:00Z","timestamp":1778674260000},"page":"2121-2130","source":"Crossref","is-referenced-by-count":1,"title":["COVID-19 vaccination in pregnancy and postpartum and human milk feeding non-initiation and discontinuation"],"prefix":"10.1093","volume":"195","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0521-4131","authenticated-orcid":false,"given":"Elisabeth Brandstetter","family":"Figueroa","sequence":"first","affiliation":[{"name":"Division of Epidemiology and Community Health, School of Public Health, University of Minnesota , Minneapolis, MN ,","place":["United States"]},{"name":"Pregnancy and Child Health Research Center, HealthPartners Institute , Minneapolis, MN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriela","family":"Vazquez-Benitez","sequence":"additional","affiliation":[{"name":"Pregnancy and Child Health Research Center, HealthPartners Institute , Minneapolis, MN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kirsten","family":"Ehresmann","sequence":"additional","affiliation":[{"name":"Pregnancy and Child Health Research Center, HealthPartners Institute , Minneapolis, MN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisabeth M","family":"Seburg","sequence":"additional","affiliation":[{"name":"Pregnancy and Child Health Research Center, HealthPartners Institute , Minneapolis, MN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yihe G","family":"Daida","sequence":"additional","affiliation":[{"name":"Center for Integrated Health Care Research, Kaiser Permanente Hawaii , Honolulu, HI ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kimberly K","family":"Vesco","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Center for Health Research , Portland, OR ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abbey","family":"Sidebottom","sequence":"additional","affiliation":[{"name":"Care Delivery Research, Allina Health , Minneapolis, MN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heather S","family":"Lipkind","sequence":"additional","affiliation":[{"name":"Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Weill Cornell Medical College , New York, NY ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3705-1672","authenticated-orcid":false,"given":"Malini B","family":"DeSilva","sequence":"additional","affiliation":[{"name":"Pregnancy and Child Health Research Center, HealthPartners Institute , Minneapolis, MN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingran","family":"Cao","sequence":"additional","affiliation":[{"name":"Pregnancy and Child Health Research Center, HealthPartners Institute , Minneapolis, MN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elyse O","family":"Kharbanda","sequence":"additional","affiliation":[{"name":"Pregnancy and Child Health Research Center, HealthPartners Institute , Minneapolis, MN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristin","family":"Palmsten","sequence":"additional","affiliation":[{"name":"Pregnancy and Child Health Research Center, HealthPartners Institute , Minneapolis, MN ,","place":["United 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