{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T00:14:52Z","timestamp":1790381692297,"version":"4.1.0"},"reference-count":29,"publisher":"BMJ","issue":"1","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2022,11,11]]},"published-print":{"date-parts":[[2023,1]]},"abstract":"<jats:p>\n                    Vitamin B\n                    <jats:sub>12<\/jats:sub>\n                    deficiency is a significant public health problem globally. Although it is a well-known cause of macrocytic anaemia and in advanced cases, pancytopenia, there remains a relative paucity of cases reported in pregnancy. It is associated with an increased risk of pregnancy complications and adverse birth outcomes such as neural tube defects, preterm birth, low birth weight, neurological sequelae and intrauterine death. It has a predilection for individuals aged &gt;60 years. It has been implicated in a spectrum of neuropsychiatric disorders and it may also exert indirect cardiovascular effects. Severe vitamin B\n                    <jats:sub>12<\/jats:sub>\n                    deficiency may present with haematological abnormalities that mimic thrombotic microangiopathy such as HELLP syndrome (haemolysis, elevated liver enzymes and low platelets) or it may present as pseudothrombotic microangiopathy (Moschcowitz syndrome) characterised by anaemia, thrombocytopenia and schistocytosis. It can also closely mimic thrombotic thrombocytopenia purpura, hence posing a diagnostic challenge to the unwary physician. Serological measurement of vitamin B\n                    <jats:sub>12<\/jats:sub>\n                    levels confirms the diagnosis. Oral supplementation with vitamin B\n                    <jats:sub>12<\/jats:sub>\n                    remains a safe and effective treatment. The authors describe the case of a multiparous woman in her late 20s presenting with a plethora of non-specific symptoms at 29\n                    <jats:sup>+5<\/jats:sup>\n                    weeks\u2019 gestation. Her haemoglobin was 45\u2009g\/L, platelets 32\u00d710\n                    <jats:sup>9<\/jats:sup>\n                    \/L, vitamin B\n                    <jats:sub>12<\/jats:sub>\n                    &lt;150\u2009ng\/L and serum folate &lt;2\u2009\u00b5g\/L. She was not a vegetarian, but her diet lacked nutrition. Following parenteral B\n                    <jats:sub>12<\/jats:sub>\n                    supplementation, her haematological parameters improved. The pregnancy was carried to term. Due to the plethora of non-specific symptoms, the diagnosis can be challenging to establish. Adverse maternal or fetal outcomes may occur. Folic acid supplementation may mask an occult vitamin B\n                    <jats:sub>12<\/jats:sub>\n                    deficiency and further exacerbate or initiate neurological disease.\n                  <\/jats:p>","DOI":"10.1136\/bcr-2022-249955","type":"journal-article","created":{"date-parts":[[2023,1,12]],"date-time":"2023-01-12T09:45:21Z","timestamp":1673516721000},"page":"e249955","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":6,"title":["Vitamin B\n                    <sub>12<\/sub>\n                    deficiency presenting with a pancytopenia in pregnancy"],"prefix":"10.1136","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5499-415X","authenticated-orcid":false,"given":"Louise","family":"Dunphy","sequence":"first","affiliation":[{"name":"Department of Obstetrics, Leighton Hospital, Cheshire, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ai-Wei","family":"Tang","sequence":"additional","affiliation":[{"name":"Department of Obstetrics, Liverpool Women's Hospital, Liverpool, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2023,1,12]]},"reference":[{"key":"2025082713115322000_16.1.e249955.1","doi-asserted-by":"crossref","first-page":"1648","DOI":"10.1001\/jama.2016.2155","article-title":"Pancytopenia in a patient with hypothyroidism","volume":"315","author":"McMahon","year":"2016","journal-title":"JAMA"},{"key":"2025082713115322000_16.1.e249955.2","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.med.51.1.357"},{"key":"2025082713115322000_16.1.e249955.3","doi-asserted-by":"publisher","DOI":"10.1007\/s00125-007-0793-y"},{"key":"2025082713115322000_16.1.e249955.4","doi-asserted-by":"publisher","DOI":"10.1002\/ajh.22091"},{"key":"2025082713115322000_16.1.e249955.5","doi-asserted-by":"publisher","DOI":"10.1002\/jca.20114"},{"key":"2025082713115322000_16.1.e249955.6","doi-asserted-by":"publisher","DOI":"10.1093\/qjmed\/hcn031"},{"key":"2025082713115322000_16.1.e249955.7","doi-asserted-by":"publisher","DOI":"10.3945\/jn.115.226845"},{"key":"2025082713115322000_16.1.e249955.8","doi-asserted-by":"crossref","first-page":"423","DOI":"10.1093\/trstmh\/try078","article-title":"Neglected tropical diseases and vitamin B12: a review of the current evidence","volume":"112","author":"Layden","year":"2018","journal-title":"Trans R Soc Trop Med Hyg"},{"key":"2025082713115322000_16.1.e249955.9","doi-asserted-by":"crossref","DOI":"10.1016\/S0140-6736(80)91381-1","article-title":"Vitamin B12 and anencephaly","volume":"1","author":"Schorah","year":"1980","journal-title":"Lancet"},{"key":"2025082713115322000_16.1.e249955.10","first-page":"678","article-title":"Causes of vitamin B12 deficiency","volume":"93","author":"Belghith","year":"2015","journal-title":"Tunis Med"},{"key":"2025082713115322000_16.1.e249955.11","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2141.2009.07937.x"},{"key":"2025082713115322000_16.1.e249955.12","unstructured":"Banerjee RV , Matthews RG . 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