Vitamin D Half-life in Pregnancy and Lactation

December 1, 2015 updated by: Kerry Jones, Medical Research Council
This study measures the plasma half-life of 25-hydroxyvitamin D3 (25(OH)D3) in non-pregnant-non-lactating women, pregnant women at 30 wk gestational age and at 3 months post-partum in women who are exclusively breast-feeding.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
49

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 45 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Female

Description

Inclusion Criteria:

All participants:

  • Currently resident in West Kiang and planning to stay for the next 5 months
  • Aged between 18 and 45 y

Pregnancy:

  • > 20 wk < 30 wk pregnant (gestational age assessment by ultrasound)
  • Singleton fetus

Lactation:

  • Breast feeding

Exclusion Criteria:

All participants:

  • Severe anaemia (haemoglobin < 7 g/dL) (as per ENID protocol)
  • Known sickle cell anaemia
  • Known to be asthmatic or allergic to peanuts (already excluded from ENID)
  • Known history of liver, kidney, gut or malabsorption problems
  • Other chronic condition
  • On prescription medication
  • Taking vitamin D supplements (> 200 IU/d)
  • Broken bone in last 3 y
  • Recent infection or illness (2 weeks prior to the start of a study period)
  • Reported onset of menopause (already excluded from ENID)
  • Malaria parasitemia (prior to study period)
  • Unable to consent

Pregnant:

  • Pregnancy-related complications or on discretion of mid-wife
  • Known HIV positive

Lactation:

  • Health problem of mother or infant that may affect feeding practices

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Non-pregnant, non-lactating (NPNL)

NPNL women are age and parity matched to pregnant women. Each NPNL women is studied twice, approximately 3 months apart.

At each study period the participant receives (as the intervention) a single oral dose of stable isotope labeled 25(OH)D3.
Other: Oral dose of stable isotope labeled 25(OH)D3
At each measurement, women are given an oral dose of stable isotope labelled 25(OH)D3. Blood and urine samples are collected at baseline and on day 21 post-dose. Additional blood samples are collected post-dose on days 6,9,24,27 and 30.
Experimental: Pregnant/Lactating
Pregnant women receive (as the intervention) a single oral dose of stable isotope labeled 25(OH)D3. The same women are followed-up in lactation to repeat the same protocol.
Other: Oral dose of stable isotope labeled 25(OH)D3
At each measurement, women are given an oral dose of stable isotope labelled 25(OH)D3. Blood and urine samples are collected at baseline and on day 21 post-dose. Additional blood samples are collected post-dose on days 6,9,24,27 and 30.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Plasma concentration of stable isotope labeled 25(OH)D3
Time Frame: Samples collected on day 6, 9, 21, 24, 27 and 30 post-dose
The plasma half-life of 25(OH)D3 is calculated from the slope (k) of the disappearance of the stable isotope labeled 25(OH)D3 against time using the equation half-life=0.693/k
Samples collected on day 6, 9, 21, 24, 27 and 30 post-dose

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Plasma concentration of vitamin D metabolites and related calciotropic hormones
Time Frame: Fasting plasma samples collected at baseline and 21 days post-dose
Analytes: 25(OH)D3, 24,25(OH)2D3, 1,25(OH)2D, vitamin D binding protein, parathyroid hormone, albumin, ionised calcium, phosphate
Fasting plasma samples collected at baseline and 21 days post-dose
Urinary concentration of calcium, phosphate, creatinine and cyclic adenosine monophosphate (cAMP)
Time Frame: Samples collected at baseline and 21 days post-dose
2-hour fasting urine collection
Samples collected at baseline and 21 days post-dose
Weighed dietary intake
Time Frame: 2 days within 30 days of dose
Dietary nutrient intakes assessed by 2-day weighed food diary and nutrient intakes calculated using DINO (diet in nutrients out) analysis programme (Fitt et al, 2015)
2 days within 30 days of dose

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Medical Research Council

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
November 1, 2011

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
October 1, 2012

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
May 1, 2013

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
November 27, 2015

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
December 1, 2015

First Posted (Estimate)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
December 4, 2015

Study Record Updates

Last Update Posted (Estimate)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
December 4, 2015

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
December 1, 2015

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
December 1, 2015

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • MRC SCC1229

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