SynthesisNutrients2016
Does Maternal Vitamin D Deficiency Increase the Risk of Preterm Birth: A Meta-Analysis of Observational Studies.
Synthesis in Nutrients, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 87 papers, 7 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
87 citing papers in PubMed, 7 syntheses or guidelines pooled it, 171 citations in OpenAlex.
- Effects of vitamin D in pregnancy on maternal and offspring health-related outcomes: An umbrella review of systematic review and meta-analyses.Nutrition & diabetes · 2024Pooled it
- Effects of vitamin D supplementation on ovulation and pregnancy in women with polycystic ovary syndrome: a systematic review and meta-analysis.Frontiers in endocrinology · 2023Pooled it
- Vitamin D and Multiple Health Outcomes: An Umbrella Review of Observational Studies, Randomized Controlled Trials, and Mendelian Randomization Studies.Advances in nutrition (Bethesda, Md.) · 2022Pooled it
- The Gestational Effects of Maternal Bone Marker Molecules on Fetal Growth, Metabolism and Long-Term Metabolic Health: A Systematic Review.International journal of molecular sciences · 2022Pooled it
- Pooled it
- Vitamin D supplementation to improve pregnancy and perinatal outcomes: an overview of 42 systematic reviews.BMJ open · 2020Pooled it
- Effects of Vitamin D Supplementation During Pregnancy on Birth Size: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.Nutrients · 2019Pooled it
- Higher Maternal Body Mass Index Attenuates the Response to High-Dose Vitamin D Supplementation During Pregnancy: A Secondary Analysis of the Randomized Vitamin D Antenatal Asthma Reduction Trial (VDAART).The Journal of nutrition · 2026Trial
- The association of early pregnancy vitamin D and BMI status with composite adverse pregnancy outcomes: an ancillary analysis of the Vitamin D Antenatal Asthma Reduction Trial.The American journal of clinical nutrition · 2025Trial
- Mode of delivery and maternal vitamin D deficiency: an optimized intelligent Bayesian network algorithm analysis of a stratified randomized controlled field trial.Scientific reports · 2023Trial
- Vitamin D3 supplementation during pregnancy and lactation for women living with HIV in Tanzania: A randomized controlled trial.PLoS medicine · 2022Trial
- Relationship of maternal obesity and vitamin D concentrations with fetal growth in early pregnancy.European journal of nutrition · 2022Trial
- Transcriptome analysis of early pregnancy vitamin D status and spontaneous preterm birth.PloS one · 2020Trial
- Randomized trial of three doses of vitamin D to reduce deficiency in pregnant Mongolian women.EBioMedicine · 2019Trial
- Maternal vitamin D sufficiency and reduced placental gene expression in angiogenic biomarkers related to comorbidities of pregnancy.The Journal of steroid biochemistry and molecular biology · 2017Trial
- Effect of Two Different Multimicronutrient Supplements on Vitamin D Status in Women of Childbearing Age: A Randomized Trial.Nutrients · 2017Trial
- Maternal vitamin D status and preterm birth: an eight-year retrospective cohort study in the Southeastern United States.Journal of perinatology : official journal of the California Perinatal Association · 2026Article
- Examining the association of maternal oral health experiences with adverse birth outcomes: findings from Virginia's PRAMS survey.BMC oral health · 2026Article
- Mediation of Pre-Pregnancy Body Mass Index and Dietary Patterns with Relation to Vitamin D and Erythropoiesis-Related Micronutrients in Pregnant Women.International journal of medical sciences · 2026Article
- Maternal Vitamin D Deficiency and Its Effects on Pregnancy Outcomes.Food science & nutrition · 2026Article
27 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
There are disagreements among researchers about the association between vitamin D deficiency during pregnancy and preterm birth (PTB). Therefore, we conducted a meta-analysis of observational studies to evaluate this association. We performed a systematic literature search of PubMed, MEDLINE and the Cochrane Library through August 2015 with the following keywords: "vitamin D" or "cholecalciferol" or "25-hydroxyvitamin D" or "25(OH)D" in combination with "premature birth" or "preterm birth" or "PTB" or "preterm delivery" or "PTD" or "prematurity". Our meta-analysis of 10 studies included 10,098 participants and found that pregnant women with vitamin D deficiency (maternal serum 25 (OH) D levels < 20 ng/mL) experienced a significantly increased risk of PTB (odds ratio (OR) = 1.29, 95% confidence intervals(CI): 1.16, 1.45) with low heterogeneity (I² = 25%, p = 0.21). Sensitivity analysis showed that exclusion of any single study did not materially alter the overall combined effect. In the subgroup analyses, we found that heterogeneity was obvious in prospective cohort studies (I² = 60%, p = 0.06). In conclusion, pregnant women with vitamin D deficiency during pregnancy have an increasing risk of PTB.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.