{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T04:01:41Z","timestamp":1783569701967,"version":"3.55.0"},"reference-count":40,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2023,8,7]],"date-time":"2023-08-07T00:00:00Z","timestamp":1691366400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Latvian Council of Science","award":["lzp-2019\/1-0335"],"award-info":[{"award-number":["lzp-2019\/1-0335"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Maternal vitamin D deficiency, which is highly prevalent in pregnant women in Europe, is linked to adverse health effects for both the mother and child. The objective was to assess vitamin D status in pregnant women by evaluating their dietary and supplemental vitamin D intake, serum vitamin D levels, parathyroid hormone levels, and lifestyle factors. This cross-sectional study, with a total of 735 participants (145 pregnant and 590 up to the seventh day postpartum), took place in Latvia. Blood samples, a food frequency questionnaire, and medical documentation were used for data collection. The median serum vitamin D concentration was 34.0 ng\/mL, with pregnant women having higher levels (42.9 ng\/mL) than postpartum women (31.8 ng\/mL). There was no association between vitamin D serum concentration and dietary intake of vitamin D (p &gt; 0.05), whereas there was a significant correlation with use of vitamin D supplements (r = 0.41; p &lt; 0.001 in pregnant women and r = 0.35; p &lt; 0.001 in postpartum women). This study demonstrated that a minority of pregnant women (21.9%) had optimal serum vitamin D concentration (&gt;45 ng\/mL), and diet had no significant impact on vitamin D levels. Thus, our proposed recommendation for vitamin D intake during pregnancy was 63 mcg (2500 IU) year-round for optimal levels in pregnant women in Northeastern Europe.<\/jats:p>","DOI":"10.3390\/nu15153493","type":"journal-article","created":{"date-parts":[[2023,8,8]],"date-time":"2023-08-08T12:38:59Z","timestamp":1691498339000},"page":"3493","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Vitamin D Intake and Serum Levels in Pregnant and Postpartum Women"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8205-0639","authenticated-orcid":false,"given":"Laila","family":"Meija","sequence":"first","affiliation":[{"name":"Department of Sports and Nutrition, R\u012bga Stradi\u0146\u0161 University, 26a Anni\u0146mui\u017eas bulv\u0101ris, LV-1067 Riga, Latvia"},{"name":"Riga East Clinical University Hospital, 2 Hipokrata Street, LV-1038 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Piskurjova","sequence":"additional","affiliation":[{"name":"Department of Public Health and Epidemiology, R\u012bga Stradi\u0146\u0161 University, 9 Kronvalda bulv\u0101ris, LV-1010 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ksenija","family":"Nikolajeva","sequence":"additional","affiliation":[{"name":"Riga East Clinical University Hospital, 2 Hipokrata Street, LV-1038 Riga, Latvia"},{"name":"Doctoral Department, Faculty of Medicine, R\u012bga Stradi\u0146\u0161 University, 16 Dzirciema Street, LV-1007 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olga","family":"Aizbalte","sequence":"additional","affiliation":[{"name":"Department of Public Health and Epidemiology, R\u012bga Stradi\u0146\u0161 University, 9 Kronvalda bulv\u0101ris, LV-1010 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roberta","family":"Rezgale","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, R\u012bga Stradi\u0146\u0161 University, 16 Dzirciema Street, LV-1007 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2097-6698","authenticated-orcid":false,"given":"Aivars","family":"Lejnieks","sequence":"additional","affiliation":[{"name":"Riga East Clinical University Hospital, 2 Hipokrata Street, LV-1038 Riga, Latvia"},{"name":"Department of Internal Diseases, R\u012bga Stradi\u0146\u0161 University, 16 Dzirciema Street, LV-1007 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vinita","family":"Cauce","sequence":"additional","affiliation":[{"name":"Department of Public Health and Epidemiology, R\u012bga Stradi\u0146\u0161 University, 9 Kronvalda bulv\u0101ris, LV-1010 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1159\/000487370","article-title":"Maternal and foetal health implications of vitamin D status during pregnancy","volume":"72","author":"Morales","year":"2018","journal-title":"Ann. 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