Vitamin D Half-life in Pregnancy and Lactation
1. december 2015 opdateret af: 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.
Studieoversigt
Status
Afsluttet
Betingelser
Intervention / Behandling
Undersøgelsestype
Interventionel
Tilmelding (Faktiske)
49
Fase
- Ikke anvendelig
Deltagelseskriterier
Forskere leder efter personer, der passer til en bestemt beskrivelse, kaldet berettigelseskriterier. Nogle eksempler på disse kriterier er en persons generelle helbredstilstand eller tidligere behandlinger.
Berettigelseskriterier
Aldre berettiget til at studere
18 år til 45 år (Voksen)
Tager imod sunde frivillige
Ingen
Køn, der er berettiget til at studere
Kvinde
Beskrivelse
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
Studieplan
Dette afsnit indeholder detaljer om studieplanen, herunder hvordan undersøgelsen er designet, og hvad undersøgelsen måler.
Hvordan er undersøgelsen tilrettelagt?
Design detaljer
- Primært formål: Grundvidenskab
- Tildeling: Ikke-randomiseret
- Interventionel model: Enkelt gruppeopgave
- Maskning: Ingen (Åben etiket)
Våben og indgreb
Deltagergruppe / Arm |
Intervention / Behandling |
|---|---|
|
Eksperimentel: 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. |
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.
|
|
Eksperimentel: 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.
|
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.
|
Hvad måler undersøgelsen?
Primære resultatmål
Resultatmål |
Foranstaltningsbeskrivelse |
Tidsramme |
|---|---|---|
|
Plasma concentration of stable isotope labeled 25(OH)D3
Tidsramme: 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
|
Sekundære resultatmål
Resultatmål |
Foranstaltningsbeskrivelse |
Tidsramme |
|---|---|---|
|
Plasma concentration of vitamin D metabolites and related calciotropic hormones
Tidsramme: 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)
Tidsramme: 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
Tidsramme: 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
|
Samarbejdspartnere og efterforskere
Det er her, du vil finde personer og organisationer, der er involveret i denne undersøgelse.
Sponsor
Datoer for undersøgelser
Disse datoer sporer fremskridtene for indsendelser af undersøgelsesrekord og resumeresultater til ClinicalTrials.gov. Studieregistreringer og rapporterede resultater gennemgås af National Library of Medicine (NLM) for at sikre, at de opfylder specifikke kvalitetskontrolstandarder, før de offentliggøres på den offentlige hjemmeside.
Studer store datoer
Studiestart
1. november 2011
Primær færdiggørelse (Faktiske)
1. oktober 2012
Studieafslutning (Faktiske)
1. maj 2013
Datoer for studieregistrering
Først indsendt
27. november 2015
Først indsendt, der opfyldte QC-kriterier
1. december 2015
Først opslået (Skøn)
4. december 2015
Opdateringer af undersøgelsesjournaler
Sidste opdatering sendt (Skøn)
4. december 2015
Sidste opdatering indsendt, der opfyldte kvalitetskontrolkriterier
1. december 2015
Sidst verificeret
1. december 2015
Mere information
Begreber relateret til denne undersøgelse
Yderligere relevante MeSH-vilkår
Andre undersøgelses-id-numre
- MRC SCC1229
Disse oplysninger blev hentet direkte fra webstedet clinicaltrials.gov uden ændringer. Hvis du har nogen anmodninger om at ændre, fjerne eller opdatere dine undersøgelsesoplysninger, bedes du kontakte register@clinicaltrials.gov. Så snart en ændring er implementeret på clinicaltrials.gov, vil denne også blive opdateret automatisk på vores hjemmeside .
Kliniske forsøg med Graviditet
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King's College Hospital NHS TrustEuropean Association for the Study of the LiverRekrutteringCirrhose, lever | HELLP syndrom | Intrahepatisk kolestase af graviditet | Graviditetssygdom | AFLP - Acute Fatty Lever of PregnancyDet Forenede Kongerige
Kliniske forsøg med Oral dose of stable isotope labeled 25(OH)D3
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University of WashingtonNational Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)Afsluttet
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University of WashingtonNational Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)AfsluttetKronisk nyresygdomForenede Stater