{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T03:35:05Z","timestamp":1790393705021,"version":"4.1.0"},"reference-count":46,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2017,3,23]],"date-time":"2017-03-23T00:00:00Z","timestamp":1490227200000},"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>Vitamin B12 (B12) adequacy during pregnancy is crucial for maternal health and optimal fetal development; however, suboptimal B12 status has been reported in pregnant Canadian women. Methylmalonic acid (MMA) is a sensitive indicator of B12 status. Since few studies have measured MMA during pregnancy in Canadian women, the objective of this study was to evaluate B12 status in pregnant women living in Metro Vancouver, using both plasma total B12 and MMA. We recruited a convenience sample of 320 pregnant women between 20 and 35 gestational weeks from local healthcare facilities. Plasma total B12 concentrations indicative of deficiency (&lt;148 pmol\/L) and suboptimal B12 status (148\u2013220 pmol\/L) were found in 18% and 33% of the women, respectively. Normal plasma MMA concentration (&lt;210 nmol\/L) was observed in 82% of all women. Gestational age was a strong predictor of plasma total B12 and MMA concentration, and South Asian ethnicity of B-12 deficiency and MMA concentrations. Overall, there was a high discrepancy between the prevalence of B12 inadequacy depending on the biomarker used. Independently, however, South Asian women were at particular risk for B12 deficiency, likely due to lower animal source food intake. Further study of this vulnerable group and performance testing of B12 biomarkers is warranted.<\/jats:p>","DOI":"10.3390\/nu9040317","type":"journal-article","created":{"date-parts":[[2017,3,23]],"date-time":"2017-03-23T11:47:59Z","timestamp":1490269679000},"page":"317","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["South Asian Ethnicity Is Related to the Highest Risk of Vitamin B12 Deficiency in Pregnant Canadian Women"],"prefix":"10.3390","volume":"9","author":[{"given":"Marta","family":"Jeruszka-Bielak","sequence":"first","affiliation":[{"name":"Food Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada"},{"name":"Current address: Department of Human Nutrition, Warsaw University of Life Sciences\u2014SGGW, 02-776 Warsaw, Poland."},{"name":"Shared first-authorship."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carly","family":"Isman","sequence":"additional","affiliation":[{"name":"Food Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada"},{"name":"Shared first-authorship."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Theresa","family":"Schroder","sequence":"additional","affiliation":[{"name":"Food Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada"},{"name":"BC Children\u2019s Hospital Research Institute, Vancouver, BC V5Z 4H4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wangyang","family":"Li","sequence":"additional","affiliation":[{"name":"Food Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada"},{"name":"Current address: Medical Weight Management Centre, Coquitlam, BC V3K 7A8, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0667-4300","authenticated-orcid":false,"given":"Tim","family":"Green","sequence":"additional","affiliation":[{"name":"Food Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada"},{"name":"South Australian Health Medical Research Institute, Adelaide 5000, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yvonne","family":"Lamers","sequence":"additional","affiliation":[{"name":"Food Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada"},{"name":"BC Children\u2019s Hospital Research Institute, Vancouver, BC V5Z 4H4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,3,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1385","DOI":"10.1093\/ajcn\/76.6.1385","article-title":"Preconception homocysteine and B vitamin status and birth outcomes in Chinese women","volume":"76","author":"Ronnenberg","year":"2002","journal-title":"Am. 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