dc.contributor.author | Rogne, Tormod | |
dc.contributor.author | Tielemans, MJ | |
dc.contributor.author | Chong, MF | |
dc.contributor.author | Yajnik, CS | |
dc.contributor.author | Krishnaveni, GV | |
dc.contributor.author | Poston, Lucilla | |
dc.contributor.author | Jaddoe, VW | |
dc.contributor.author | Steegers, EA | |
dc.contributor.author | Joshi, S | |
dc.contributor.author | Chong, YS | |
dc.contributor.author | Godfrey, KM* | |
dc.contributor.author | Yap, F | |
dc.contributor.author | Yahyaoui, R | |
dc.contributor.author | Thomas, T | |
dc.contributor.author | Hay, Gry | |
dc.contributor.author | Hogeveen, M | |
dc.contributor.author | Demir, Ahmet | |
dc.contributor.author | Saravanan, P | |
dc.contributor.author | Skovlund, Eva | |
dc.contributor.author | Martinussen, Marit | |
dc.contributor.author | Jacobsen, Geir Wenberg | |
dc.contributor.author | Franco, OH | |
dc.contributor.author | Bracken, Michael B | |
dc.contributor.author | Risnes, Kari | |
dc.date.accessioned | 2017-02-01T08:26:18Z | |
dc.date.available | 2017-02-01T08:26:18Z | |
dc.date.created | 2017-01-29T15:17:26Z | |
dc.date.issued | 2017 | |
dc.identifier.issn | 0002-9262 | |
dc.identifier.uri | http://hdl.handle.net/11250/2429099 | |
dc.description | available from 2018-02-01 | |
dc.description.abstract | Vitamin B12 (hereafter referred to as B12) deficiency in pregnancy is prevalent and has been associated with both lower birth weight (birth weight <2,500 g) and preterm birth (length of gestation <37 weeks). Nevertheless, current evidence is contradictory. We performed a systematic review and a meta-analysis of individual participant data to evaluate the associations of maternal serum or plasma B12 concentrations in pregnancy with offspring birth weight and length of gestation. Twenty-two eligible studies were identified (11,993 observations). Eighteen studies were included in the meta-analysis (11,216 observations). No linear association was observed between maternal B12 levels in pregnancy and birth weight, but B12 deficiency (<148 pmol/L) was associated with a higher risk of low birth weight in newborns (adjusted risk ratio = 1.15, 95% confidence interval (CI): 1.01, 1.31). There was a linear association between maternal levels of B12 and preterm birth (per each 1-standard-deviation increase in B12, adjusted risk ratio = 0.89, 95% CI: 0.82, 0.97). Accordingly, B12 deficiency was associated with a higher risk of preterm birth (adjusted risk ratio = 1.21, 95% CI: 0.99, 1.49). This finding supports the need for randomized controlled trials of vitamin B12 supplementation in pregnancy. | nb_NO |
dc.language.iso | eng | nb_NO |
dc.publisher | Oxford university press | nb_NO |
dc.subject | low birth weight, pregnancy, preterm birth, systematic review, vitamin B12 | nb_NO |
dc.title | Associations of Maternal Vitamin B12 Concentration in Pregnancy With the Risks of Preterm Birth and Low Birth Weight: A Systematic Review and Meta-Analysis of Individual Participant Data | nb_NO |
dc.type | Journal article | nb_NO |
dc.type | Peer reviewed | nb_NO |
dc.source.journal | American Journal of Epidemiology | nb_NO |
dc.identifier.doi | 10.1093/aje/kww212 | |
dc.identifier.cristin | 1440183 | |
dc.description.localcode | Akseptert fagfellevurdert versjon/postprint | nb_NO |
dc.description.localcode | This article has been accepted for publication in American Journal of Epidemiology Published by Oxford University Press. | |
cristin.unitcode | 194,65,20,0 | |
cristin.unitcode | 194,65,10,0 | |
cristin.unitname | Institutt for samfunnsmedisin | |
cristin.unitname | Institutt for laboratoriemedisin, barne- og kvinnesykdommer | |
cristin.ispublished | true | |
cristin.fulltext | postprint | |
cristin.qualitycode | 2 | |