Understanding vitamin D dynamics in pregnant women

Vitamin D Dynamics in Pregnant Women and Non-Pregnant Women of Reproductive Age

Cornell University · NCT02705287

This study looks at how vitamin D works in pregnant women and how things like weight and genetics affect its absorption to help improve health for moms and their babies.

Quick facts

Study typeObservational
Enrollment160 (estimated)
Ages20 Years to 39 Years
SexFemale
SponsorCornell University (other)
Locations1 site (Rochester, New York)
Trial IDNCT02705287 on ClinicalTrials.gov

What this trial studies

This observational study aims to investigate the dynamics of vitamin D during pregnancy using stable isotopically labeled vitamin D3 and advanced mass spectrometric techniques. It focuses on how factors such as obesity and vitamin D binding protein genotype affect vitamin D absorption and utilization in pregnant women. The study will gather data on vitamin D metabolism throughout different stages of pregnancy to better understand its implications for maternal and fetal health. The ultimate goal is to provide insights that could inform guidelines for vitamin D intake during pregnancy.

Who should consider this trial

Good fit: Ideal candidates for this study are self-reported White and Black women aged 20-39 with a BMI within specified ranges, either pregnant or non-pregnant.

Not a fit: Patients with a BMI below 18.5 kg/m2, certain medical conditions, or those on medications affecting vitamin D metabolism may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved guidelines for vitamin D supplementation during pregnancy, potentially enhancing maternal and fetal health outcomes.

How similar studies have performed: While there is limited direct research on vitamin D dynamics in pregnant women, previous studies have indicated the importance of vitamin D in pregnancy, suggesting that this approach could yield valuable insights.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria (Non-pregnant and pregnant participants participants):

* Self-reported White and Black women
* Age 20-39
* Body mass index (BMI) 1or pre-pregnancy BMI (If currently pregnant) either 18.5-24.9 kg/m2 or greater than or equal to 30 kg/m2

Inclusion Criteria (Additional criteria for pregnant participants):

* Singleton pregnancy
* Recruited in first trimester, second trimester, or third trimester
* No pregnancy complications

Exclusion Criteria (Non-pregnant and pregnant participants):

* BMI or pre-pregnancy BMI \<18.5 kg/m2
* Human immunodeficiency virus (HIV) infection
* Diagnosed eating disorder
* Malabsorption disease
* Diabetes
* Elevated diastolic blood pressure (\>110 mm/Hg)
* Steroid use
* Substance abuse history
* Current use of medications known to influence vitamin D or calcium homeostasis
* Plans to travel to lower latitude during the 20-day study period
* Plans to become pregnant during the study period (non-pregnant only)
* Refuses to discontinue tanning bed use during study period
* Refuses to discontinue vitamin or mineral supplement use during study period (non-pregnant only)

Exclusion Criteria (Additional criteria for pregnant participants):

* Gestational diabetes
* Pregnancy hypertension

Where this trial is running

Rochester, New York

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Pregnancy, vitamin D, half life, kinetics

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.