Related Experiment Video
Updated: Jul 31, 2025
Author Spotlight: Studying the Impact of Maternal Dietary Deficiencies on Long-Term Offspring Health Outcomes
Published on: June 28, 2024
Vitamin D deficiency in pregnancy and the risk of preterm birth: a nested case-control study
Tashnia Tahsin1, Rasheda Khanam2, Nabidul Haque Chowdhury3
1Department of Medicine, West Virginia University, Morgantown, WV, USA.
Insights
Vitamin D deficiency (VDD) is prevalent in pregnant Bangladeshi women and significantly increases the risk of preterm birth (PTB). Addressing VDD may help reduce PTB rates in this population.
Area of Science:
- Maternal-fetal medicine
- Nutritional science
- Public health
Background:
- Micronutrient deficiencies, including vitamin D deficiency (VDD), are widespread in low- and middle-income countries (LMICs).
- Bangladesh has a high prevalence of VDD and a high rate of preterm birth (PTB).
- Understanding the link between VDD and PTB is crucial for improving maternal and infant outcomes.
Purpose of the Study:
- To estimate the prevalence of VDD during pregnancy in Bangladesh.
- To investigate the association between VDD and PTB using population-based cohort data.
Main Methods:
- A nested case-control study was conducted with 3,000 pregnant women.
- Maternal blood samples were collected at 24-28 weeks of gestation to measure 25(OH)D concentrations.
- Logistic regression analysis was used to determine the association between VDD (25(OH)D < 30.25 nmol/L) and PTB, adjusting for confounders.
Main Results:
- The median 25(OH)D level was 38.0 nmol/L, indicating widespread VDD.
- VDD was significantly associated with an increased risk of PTB (aOR = 1.53, 95% CI: 1.10-2.12).
- Other risk factors for PTB included shorter maternal height, primiparity, passive smoking, and iron supplementation.
Conclusions:
- Vitamin D deficiency is common among pregnant women in Bangladesh.
- VDD is a significant risk factor associated with an increased risk of preterm birth.
Background:
Each year, an estimated 15 million babies are born preterm. Micronutrient deficiencies, including vitamin D deficiency (VDD), are common in many low- and middle-income countries (LMICs), and these conditions are often associated with adverse pregnancy outcomes. Bangladesh experiences a high prevalence of VDD. The country also has a high preterm birth (PTB) rate. Using data from a population-based pregnancy cohort, we estimated the burden of VDD during pregnancy and its association with PTB.
Methods:
Pregnant women (N = 3,000) were enrolled after ultrasound confirmation of gestational age at 8-19 weeks of gestation. Trained health workers prospectively collected phenotypic and epidemiological data at scheduled home visits. Trained phlebotomists collected maternal blood samples at enrollment and 24 -28 weeks of gestation. Aliquots of serum were stored at -800 C. We conducted a nested case-control study with all PTB (n = 262) and a random sample of term births (n = 668). The outcome, PTB, was defined as live births < 37 weeks of gestation, based on ultrasound. The main exposure was vitamin D concentrations of 24-28 weeks maternal blood samples. The analysis was adjusted for other PTB risk factors. Women were categorized as VDD (lowest quartile of 25(OH)D; < = 30.25 nmol/L) or not deficient (upper-three quartiles of 25(OH)D; > 30.25 nmol/L). We used logistic regression to determine the association of VDD with PTB, adjusting for potential confounders.
Results:
The median and interquartile range of serum 25(OH)D was 38.0 nmol/L; 30.18 to 48.52 (nmol/L). After adjusting for co-variates, VDD was significantly associated with PTB [adjusted odds ratio (aOR) = 1.53, 95% confidence interval (CI) = 1.10 - 2.12]. The risk of PTB was also higher among women who were shorter (aOR = 1.81, 95% CI: 1.27-2.57), primiparous (aOR = 1.55, 95% CI = 1.12 - 2.12), passive smokers (aOR = 1.60, 95% CI = 1.09 - 2.34), and those who received iron supplementation during pregnancy (aOR = 1.66, 95% CI: 1.17, 2.37).
Conclusion:
VDD is common in Bangladeshi pregnant women and is associated with an increased risk of PTB.
More Related Videos
14:43A Novel Method for Involving Women of Color at High Risk for Preterm Birth in Research Priority Setting
Published on: January 12, 2018
12:02Human Primary Trophoblast Cell Culture Model to Study the Protective Effects of Melatonin Against Hypoxia/reoxygenation-induced Disruption
Published on: July 30, 2016
Related Concept Videos
01:23Role of Skin in Vitamin D Synthesis
The solar UV B rays (290-315 nm) are absorbed by the skin, and 7-dehydrocholesterol (provitamin D3) photolyzes it to previtamin D3, which undergoes a rapid transformation to vitamin...
01:30Vitamins
01:20Pathophysiology of Diabetes
Type 1 diabetes is characterized by autoimmune-mediated destruction of pancreatic β cells, with environmental factors potentially triggering this process in genetically susceptible individuals. Despite many not having a family history, certain genes increase susceptibility,...
01:07Teratogenicity
01:22Diabetes Mellitus: Type 2 and Gestational
01:22Development of Immunocompetence
The initial cells that migrate from the fetal thymus settle within the skin and epithelial tissues lining the mouth, digestive tract, and in females, the uterus and vagina. These cells, including skin-based dendritic cells, serve as antigen-presenting cells, playing a key role in T cell activation.
Subsequent T...