ArticlePloS one2018
Alterations in the vitamin D endocrine system during pregnancy: A longitudinal study of 855 healthy Norwegian women.
Article in PloS one, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 27 papers.
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Who cites it
27 citing papers in PubMed.
- Maternal vitamin A and D status in second and third trimester of pregnancy and bone mineral content in offspring at nine years of age.Frontiers in endocrinology · 2024Trial
- Does antenatal cholecalciferol supplementation affect the mode or timing of delivery? Post hoc analyses of the MAVIDOS randomized controlled trial.Journal of public health (Oxford, England) · 2023Trial
- Basal Vitamin D Status and Supplement Dose Are Primary Contributors to Maternal 25-Hydroxyvitamin D Response to Prenatal and Postpartum Cholecalciferol Supplementation.The Journal of nutrition · 2021Trial
- The effect of an exercise program in pregnancy on vitamin D status among healthy, pregnant Norwegian women: a randomized controlled trial.BMC pregnancy and childbirth · 2019Trial
- Dietary Intakes and Dietary Quality during Pregnancy in Women with and without Gestational Diabetes Mellitus-A Norwegian Longitudinal Study.Nutrients · 2018Trial
- Maternal fat-soluble vitamin trajectories and infant birth weight in individuals with overweight or obesity.Frontiers in endocrinology · 2026Article
- Maternal vitamin A levels during second and third trimester and associations with offspring's birth weight: a longitudinal cohortFrontiers in nutrition · 2026Article
- Vitamin D and Gestational Diabetes Mellitus in the IEU OpenGWAS Project: A Two-Sample Bidirectional Mendelian Randomization Study.Nutrients · 2024Article
- Vitamin D intake and determinants of vitamin D status during pregnancy in The Norwegian Mother, Father and Child Cohort Study.Frontiers in nutrition · 2023Article
- Article
- Bone metabolism and osteoporosis during pregnancy and lactation.Archives of osteoporosis · 2022Review
- Dietary Intake in Early Pregnancy and Glycemia in Late Pregnancy among Women with Obesity.Nutrients · 2021Article
- Could Vitamin D Be Effective in Prevention of Preeclampsia?Nutrients · 2021Review
- Higher maternal parathyroid hormone concentration at delivery is not associated with smaller newborn size.Endocrine connections · 2021Article
- Opposite correlation of 25-hydroxy-vitamin D- and 1,25-dihydroxy-vitamin D-metabolites with gestational age, bone- and lipid-biomarkers in pregnant women.Scientific reports · 2021Article
- The role of vitamin D in perinatology. An up-to-date review.Archives of medical science : AMS · 2021Article
- Standardization of laboratory practices and reporting of biomarker data in clinical nutrition research.The American journal of clinical nutrition · 2020Article
- Validation and Determination of 25(OH) Vitamin D and 3-Epi25(OH)D3 in Breastmilk and Maternal- and Infant Plasma during Breastfeeding.Nutrients · 2020Article
- Early Pregnancy Vitamin D Binding Protein Is Independently Associated with the Development of Gestational Diabetes: A Retrospective Cohort Study.Journal of clinical medicine · 2020Article
- Vitamin D-Binding Protein in Pregnancy and Reproductive Health.Nutrients · 2020Review
Corrections and comments
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Authors and funding
9 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
To ensure optimal calcium accrual in the fetal skeleton, a substantial rise occurs in 1,25-dihydroxyvitamin D (1,25(OH)2D), but is dependent on sufficient 25-hydroxyvitamin (25(OH)D). Large longitudinal studies addressing free 25(OH)D and 1,25(OH)2D during pregnancy are scarce. We aimed to assess levels of and relationship between 25(OH)D, 1,25(OH)2D, vitamin D-binding protein (DBP), parathyroid hormone (PTH), and free 25(OH)D during pregnancy; determinants of vitamin D status; and association between vitamin D indices or PTH and pregnancy outcomes (gestational diabetes mellitus and birthweight). Altogether 855 pregnant Norwegian Caucasian women from Trondheim and Stavanger (latitude 63°N and 58°N) were recruited; 94 were lost to follow-up. The study was originally a randomized controlled trial (2007-2009) with gestational diabetes as primary outcome. Data were collected in second and third trimester. In third trimester, 246 (34%) had vitamin D insufficiency and 52 (7%) deficiency (25(OH)D <50 and <30nmol/L, respectively). During wintertime in third trimester, 61 (47%) from Trondheim and 23 (51%) from Stavanger exhibited vitamin D insufficiency. PTH was elevated in 27 (3.7%). Estimate of change between trimesters was (95% CI): 25(OH)D -1.8 (-2.8 to -0.7) nmol/L, DBP 0.62 (0.57 to 0.66) μmol/L, calculated free 25(OH)D -1.7 (-2.0 to -1.4) pmol/L, PTH 0.81 (0.72 to 0.90) pmol/L, 1,25(OH)2D (sub-analysis) 31.4 (CI 24.7 to 38.2) pmol/L. A decrease in 1,25(OH)2D occurred in 45% of those with vitamin D deficiency, and they also exhibited lower levels than women with adequate vitamin D status. No association of vitamin D indices and PTH with pregnancy outcomes was observed. Women in Trondheim displayed lower 25(OH)D levels, despite minor latitudinal differences. Less than one-fifth adhered to the authorities' vitamin D recommendations. These findings demonstrate that hypovitaminosis D is prevalent among pregnant women living in northern latitudes, especially during the dark season, and there is an unmet need to ensure adequate vitamin D intake.
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