Vitamin D DeficiencyPREDINNCT05329428
PREDIN: Pregnancy and Vitamin D Intervention Study
A study testing Vitamin D Supplementation 20 µg/day, Vitamin D Supplementation 40 µg/day and Usual Antenatal Care in people with Vitamin D Deficiency and Vitamin D3 Deficiency, run by Göteborg University at 1 site in Sweden.
Trial summary
Vitamin D deficiency is common among certain risk groups in Sweden, and occurs approximately in every tenth pregnant woman.The aim of the randomized double-blind controlled trial Pregnancy vitamin D intervention (PREDIN) is to investigate the dose of vitamin D supplementation required in achieving vitamin D… Read more about this study
- Who is it for?
- Ages 18 to 45 years, women only
- Conditions the study is for
- Vitamin D Deficiency, Vitamin D3 Deficiency, Pregnancy Complications
- What is being tested?
- Vitamin D Supplementation 20 µg/day, Vitamin D Supplementation 40 µg/day and Usual Antenatal Care
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 105 participants
- Where
- 1 siteSweden
- Study dates
- 14 Apr 2022to 16 Sep 2024
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 45 years
- Women only
- No healthy volunteers
- Adult
Who may be able to join
- pregnant women in gestational week <15
Who cannot join
- multi-fetal pregnancy
- known disorder to the metabolism of vitamin D, calcium or phosphate (e.g. adrenal gland disorders, kidney disease)
- ongoing treatment with vitamin D of ≥10 µg/day
- difficulties understanding the study information
Trial locations and contacts
1 site in 1 country.
About this study
Official title: PREDIN: Pregnancy and Vitamin D Intervention Study - A Randomized Controlled Trial
Vitamin D deficiency is common among certain risk groups in Sweden, and occurs approximately in every tenth pregnant woman.The aim of the randomized double-blind controlled trial Pregnancy vitamin D intervention (PREDIN) is to investigate the dose of vitamin D supplementation required in achieving vitamin D sufficiency (25OHD ≥50 nmol/l) in pregnant women at risk of vitamin D deficiency. In addition, the investigators aim to examine if the overall vitamin D status and vitamin D intake have increased since the expanded vitamin D fortification program was initiated in year 2020.
Read the detailed description
The effect of maternal vitamin D in pregnancy for maternal and offspring health needs to be clarified. In observational studies, the investigators and others show associations between poor maternal vitamin D status in pregnancy and an increased risk of pregnancy complications. Poor maternal vitamin D status is also linked to impaired growth in the first year of life, and potentially also to higher risk of developing obesity in childhood. Risk factors for vitamin D deficiency in Swedish pregnant women are related to lower intake of vitamin D and to less sun exposure.
Since the evidence for positive effects of maternal vitamin D status or intake is limited, vitamin D interventions in pregnancy are warranted to clarify the causal effects of vitamin D in pregnancy and the doses required to achieve sufficient vitamin D status in deficient women. In the first trimester, pregnant women will be screened at a routine visit in the antenatal care for the risk of vitamin D deficiency using a validated questionnaire. Women who are classified as having a high risk of vitamin D deficiency will be randomized to one of three study arms: usual antenatal care, 20 µg vitamin D per day or 40 µg vitamin D per day. The participants will be followed up until delivery. Blood will be collected for analysis of vitamin D status (25OHD) at screening and in the third trimester of pregnancy. Information regarding pregnancy, gestational complication and fetal growth will be retrieved from medical records after delivery. About 500 women will be screened and their vitamin D status and vitamin D intake will be compared to a previous population-based cohort study, to investigate if the status or intake of vitamin D has increased since the expanded food fortification program was introduced.
The study hypothesis is that vitamin D status and/or vitamin D intake is related to risk of developing complications during pregnancy or delivery and that maternal supplementation with vitamin D during pregnancy will be effective in achieving vitamin D sufficiency in pregnant women at risk of vitamin D deficiency. In addition, the investigators hypothesize that the expanded vitamin D food fortification program has increased the vitamin D status and vitamin D intake of pregnant women in Gothenburg since 2013-2014.
- Being tested
- Vitamin D Supplementation 20 µg/day, Vitamin D Supplementation 40 µg/day, Usual Antenatal Care
- Medical subject headings
- Vitamin D Deficiency, Pregnancy Complications
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Vitamin D Supplementation 20 µg/dayDietary supplement
At a routine visit at the antenatal care in early pregnancy (gestational week <15) women will be provided with with vitamin D3 (cholecalciferol) supplements. Two tablets, with a total content of 20 µg (800 IE), are taken daily throughout pregnancy.
Vitamin D Supplementation 40 µg/dayDietary supplement
At a routine visit at the antenatal care in early pregnancy (gestational week <15) women will be provided with with vitamin D3 (cholecalciferol) supplements. Two tablets, with a total content of 40 µg (1600 IE), are taken daily throughout pregnancy.
Usual Antenatal CareOther
In early pregnancy (gestational week <15) women are advised by the regular midwife to take a daily supplement of Vitamin D throughout pregnancy, according to usual antenatal care routines.
| Study group | Role | What they receive |
|---|---|---|
| Vitamin D Supplementation 20 µg/day | Experimental | Dietary supplements containing 20 µg of vitamin D per day will be provided to study subjects. Receives: Dietary Supplement: Vitamin D Supplementation 20 µg/day |
| Vitamin D Supplementation 40 µg/day | Experimental | Dietary supplements containing 40 µg of vitamin D per day will be provided to study subjects. Receives: Dietary Supplement: Vitamin D Supplementation 40 µg/day |
| Usual Antenatal Care | Active comparator | Women randomized to usual antenatal care will receive advise about vitamin D supplementation according to usual antenatal care routines. Receives: Other: Usual Antenatal Care |
What is being measured
The primary outcome is the main question the study is designed to answer.
Difference in maternal vitamin D status (25OHD) between intake of vitamin D supplements containing either 40 µg per day or 20 µg per day during pregnancy
Analyses of 25OHD (25OHD3 and 25OHD2) from blood samples drawn in first- and third trimester of pregnancy
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Difference in maternal vitamin D status (25OHD) between intake of vitamin D supplements (both 40 µg per day or 20 µg per day) during pregnancy and usual antenatal care routines
Analyses of 25OHD (25OHD3 and 25OHD2) from blood samples drawn in first- and third trimester of pregnancy
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Difference in maternal 3-epi-25-Hydroxyvitamin D between the three groups; intakes of vitamin D supplements 40 µg/day or 20 µg/day or usual antenatal care routines
Analyses of vitamin D metabolites 3-epi-25-Hydroxyvitamin D3 from blood samples drawn in first- and third trimester of pregnancy
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Difference in maternal 1,25-dihydroxyvitamin D between the three groups; intakes of vitamin D supplements 40 µg/day or 20 µg/day or usual antenatal care routines
Analyses of 1,25-dihydroxyvitamin D from blood samples drawn in first- and third trimester of pregnancy
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Difference in maternal vitamin D binding proteins between the three groups; intakes of vitamin D supplements 40 µg/day or 20 µg/day or usual antenatal care routines
Analyses of vitamin D binding proteins from blood samples drawn in first- and third trimester of pregnancy
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Secondary outcomes (25)
Gene variant related to vitamin D metabolism
Analyses of gene variants in blood sample drawn at inclusion in first trimester of pregnancy
Measured: At inclusion in first trimester of pregnancy
Ferritin
Analyses of ferritin
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Hemoglobin
Analyses of hemoglobin
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Metabolomics
Analyses of metabolomics in blood
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
C-reactive protein
Analyses of inflammation e.g. c-reactive protein
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Interleukines
Analyses of inflammation e.g. interleukines
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Cytokines
Analyses of inflammation e.g. cytokines
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Cortisol
Analyses of cortisol
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Parathyroid hormone
Analysis of parathyroid hormone in sampled blood at the routine laboratory
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Estrogen
Analyses of estrogen, in sampled blood, at the routine laboratory
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Progesterone
Analyses of progesterone, in sampled blood, at the routine laboratory
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
24,25-Dihydroxyvitamin D
Analyses of 24,25(OH)2D (24,25(OH)2D3 and 24,25(OH)2D2)
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Dietary intake
Dietary intake of mother during pregnancy assessed by dietary record at two time points
Measured: At inclusion in first trimester and at follow-up in third trimester, up to 9 months
Body weight development
Self-reported weight (in kilograms) during pregnancy until delivery.
Measured: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Incidence of pregnancy-induced hypertension
Diagnosis of pregnancy-induced hypertension
Measured: Up to delivery
Incidence of pre-eclampsia
Diagnosis of pre-eclampsia
Measured: Up to delivery
Incidence of gestational diabetes
Diagnosis of gestational diabetes
Measured: Up to delivery (up to 9 months)
Incidence of preterm delivery
Delivery before 37 weeks completed weeks of gestation
Measured: Up to 37 completed weeks
Incidence of small for gestational age (SGA)
SGA born infant
Measured: At delivery
Incidence of large for gestational age (LGA)
LGA born infant
Measured: At delivery
Incidence of Intrauterine growth restriction (IUGR)
IUGR
Measured: At delivery
Apgar scores
Vitality signs are estimated as Apgar scores at 1, 5 and 10 minutes after birth of the newborn. Apgar stands for Appearance, pulse, grimace, activity and respiration. The maximium score at each time point is 10 scores and a high score indicates high vitality, where as a low score indicates very low vitality.
Measured: At 1, 5 and 10 minutes after delivery
Incidence of Caesarean sections
Delivery by caesarean sections
Measured: At delivery
Incidence of miscarriage
Miscarriage
Measured: During the first 21+6 weeks of pregnancy
Incidence of Intrauterine fetal demise (IUFD)
IUFD
Measured: Any time during pregnancy after pregnancy week 22+0 (up to 9 months)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Apr 2022
- Study start14 Apr 2022
- Primary completion18 Jul 2024
- Study completion16 Sep 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Vitamin D DeficiencyStudies of the same condition, open and under way.
- More trials run by Göteborg UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Care provider
- Enrolment
- 105 participants (actual)
Sponsor and investigators
- Lead sponsor
- Göteborg University
- Sponsor type
- University, hospital or other
- Collaborators
- Vastra Gotaland Region
- Responsible party
- Sponsor
- Investigators
- Hanna Augustin, Ass Prof, Principal investigator, Göteborg University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05329428
- Sponsor's protocol ID
- 2021-03871
- Acronym
- PREDIN
- Status last verified
- Oct 2025
- First submitted
- 9 Dec 2021
- Last updated
- 11 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Karlsson T, Forsby M, Hagman A, Jerhamre-Sundh K, Hoppe M, Augustin H. Iron Status During Early and Late Pregnancy in a Swedish Multiethnic Population. Anemia. 2026 Oct 22;2026:7110858. doi: 10.1155/anem/7110858. eCollection 2026.
PubMed 42920799
Study at a glance
From the registry record, last updated by the sponsor on 11 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- PREDIN: Pregnancy and Vitamin D Intervention Study - A Randomized Controlled Trial
- ClinicalTrials.gov ID
- NCT05329428
- Acronym / sponsor ID
- PREDIN / 2021-03871
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 105 participants (actual)
- Lead sponsor
- Göteborg UniversityUniversity, hospital or other
- Collaborators
- Vastra Gotaland Region
- Study start
- 14 Apr 2022 (actual)
- Primary completion
- 18 Jul 2024 (actual)
- Study completion
- 16 Sep 2024 (actual)
- First posted
- 15 Apr 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Vitamin D deficiency is common among certain risk groups in Sweden, and occurs approximately in every tenth pregnant woman.The aim of the randomized double-blind controlled trial Pregnancy vitamin D intervention (PREDIN) is to investigate the dose of vitamin D supplementation required in achieving vitamin D sufficiency (25OHD ≥50 nmol/l) in pregnant women at risk of vitamin D deficiency. In addition, the investigators aim to examine if the overall vitamin D status and vitamin D intake have increased since the expanded vitamin D fortification program was initiated in year 2020.
Detailed description
The effect of maternal vitamin D in pregnancy for maternal and offspring health needs to be clarified. In observational studies, the investigators and others show associations between poor maternal vitamin D status in pregnancy and an increased risk of pregnancy complications. Poor maternal vitamin D status is also linked to impaired growth in the first year of life, and potentially also to higher risk of developing obesity in childhood. Risk factors for vitamin D deficiency in Swedish pregnant women are related to lower intake of vitamin D and to less sun exposure.
Since the evidence for positive effects of maternal vitamin D status or intake is limited, vitamin D interventions in pregnancy are warranted to clarify the causal effects of vitamin D in pregnancy and the doses required to achieve sufficient vitamin D status in deficient women. In the first trimester, pregnant women will be screened at a routine visit in the antenatal care for the risk of vitamin D deficiency using a validated questionnaire. Women who are classified as having a high risk of vitamin D deficiency will be randomized to one of three study arms: usual antenatal care, 20 µg vitamin D per day or 40 µg vitamin D per day. The participants will be followed up until delivery. Blood will be collected for analysis of vitamin D status (25OHD) at screening and in the third trimester of pregnancy. Information regarding pregnancy, gestational complication and fetal growth will be retrieved from medical records after delivery. About 500 women will be screened and their vitamin D status and vitamin D intake will be compared to a previous population-based cohort study, to investigate if the status or intake of vitamin D has increased since the expanded food fortification program was introduced.
The study hypothesis is that vitamin D status and/or vitamin D intake is related to risk of developing complications during pregnancy or delivery and that maternal supplementation with vitamin D during pregnancy will be effective in achieving vitamin D sufficiency in pregnant women at risk of vitamin D deficiency. In addition, the investigators hypothesize that the expanded vitamin D food fortification program has increased the vitamin D status and vitamin D intake of pregnant women in Gothenburg since 2013-2014.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, care provider)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Vitamin D Supplementation 20 µg/day | Experimental | Dietary Supplement: Vitamin D Supplementation 20 µg/dayDietary supplements containing 20 µg of vitamin D per day will be provided to study subjects. |
| Vitamin D Supplementation 40 µg/day | Experimental | Dietary Supplement: Vitamin D Supplementation 40 µg/dayDietary supplements containing 40 µg of vitamin D per day will be provided to study subjects. |
| Usual Antenatal Care | Active comparator | Other: Usual Antenatal CareWomen randomized to usual antenatal care will receive advise about vitamin D supplementation according to usual antenatal care routines. |
Who may qualify
- Ages
- 18 to 45 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (1 listed)
- pregnant women in gestational week <15
Key exclusion criteria (4 listed)
- multi-fetal pregnancy
- known disorder to the metabolism of vitamin D, calcium or phosphate (e.g. adrenal gland disorders, kidney disease)
- ongoing treatment with vitamin D of ≥10 µg/day
- difficulties understanding the study information
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Vitamin D Supplementation 20 µg/dayAt a routine visit at the antenatal care in early pregnancy (gestational week <15) women will be provided with with vitamin D3 (cholecalciferol) supplements. Two tablets, with a total content of 20 µg (800 IE), are taken daily throughout pregnancy. | Dietary supplement | Vitamin D Supplementation 20 µg/day |
| Vitamin D Supplementation 40 µg/dayAt a routine visit at the antenatal care in early pregnancy (gestational week <15) women will be provided with with vitamin D3 (cholecalciferol) supplements. Two tablets, with a total content of 40 µg (1600 IE), are taken daily throughout pregnancy. | Dietary supplement | Vitamin D Supplementation 40 µg/day |
| Usual Antenatal CareIn early pregnancy (gestational week <15) women are advised by the regular midwife to take a daily supplement of Vitamin D throughout pregnancy, according to usual antenatal care routines. | Other | Usual Antenatal Care |
Primary outcome
Difference in maternal vitamin D status (25OHD) between intake of vitamin D supplements containing either 40 µg per day or 20 µg per day during pregnancy
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Analyses of 25OHD (25OHD3 and 25OHD2) from blood samples drawn in first- and third trimester of pregnancy
Difference in maternal vitamin D status (25OHD) between intake of vitamin D supplements (both 40 µg per day or 20 µg per day) during pregnancy and usual antenatal care routines
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Analyses of 25OHD (25OHD3 and 25OHD2) from blood samples drawn in first- and third trimester of pregnancy
Difference in maternal 3-epi-25-Hydroxyvitamin D between the three groups; intakes of vitamin D supplements 40 µg/day or 20 µg/day or usual antenatal care routines
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Analyses of vitamin D metabolites 3-epi-25-Hydroxyvitamin D3 from blood samples drawn in first- and third trimester of pregnancy
Difference in maternal 1,25-dihydroxyvitamin D between the three groups; intakes of vitamin D supplements 40 µg/day or 20 µg/day or usual antenatal care routines
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Analyses of 1,25-dihydroxyvitamin D from blood samples drawn in first- and third trimester of pregnancy
Difference in maternal vitamin D binding proteins between the three groups; intakes of vitamin D supplements 40 µg/day or 20 µg/day or usual antenatal care routines
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Analyses of vitamin D binding proteins from blood samples drawn in first- and third trimester of pregnancy
25 secondary outcomes
Gene variant related to vitamin D metabolism
Time frame: At inclusion in first trimester of pregnancy
Ferritin
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Hemoglobin
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Metabolomics
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
C-reactive protein
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Interleukines
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Cytokines
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Cortisol
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Parathyroid hormone
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Estrogen
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Progesterone
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
24,25-Dihydroxyvitamin D
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Dietary intake
Time frame: At inclusion in first trimester and at follow-up in third trimester, up to 9 months
Body weight development
Time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Incidence of pregnancy-induced hypertension
Time frame: Up to delivery
Incidence of pre-eclampsia
Time frame: Up to delivery
Incidence of gestational diabetes
Time frame: Up to delivery (up to 9 months)
Incidence of preterm delivery
Time frame: Up to 37 completed weeks
Incidence of small for gestational age (SGA)
Time frame: At delivery
Incidence of large for gestational age (LGA)
Time frame: At delivery
Incidence of Intrauterine growth restriction (IUGR)
Time frame: At delivery
Apgar scores
Time frame: At 1, 5 and 10 minutes after delivery
Incidence of Caesarean sections
Time frame: At delivery
Incidence of miscarriage
Time frame: During the first 21+6 weeks of pregnancy
Incidence of Intrauterine fetal demise (IUFD)
Time frame: Any time during pregnancy after pregnancy week 22+0 (up to 9 months)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 11 Mar 2026.
- Derived from this study: PubMed 42920799Karlsson T, Forsby M, Hagman A, Jerhamre-Sundh K, Hoppe M, Augustin H. Iron Status During Early and Late Pregnancy in a Swedish Multiethnic Population. Anemia. 2026 Oct 22;2026:7110858. doi: 10.1155/anem/7110858. eCollection 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Hanna Augustin, Ass Prof principal investigator
Göteborg University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Vitamin D Supplementation 20 µg/day, Vitamin D Supplementation 40 µg/day and Usual Antenatal Care in people with Vitamin D Deficiency and Vitamin D3 Deficiency, run by Göteborg University at 1 site in Sweden.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 11 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Sweden. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Difference in maternal vitamin D status (25OHD) between intake of vitamin D supplements containing either 40 µg per day or 20 µg per day during pregnancy (time frame: From inclusion in first trimester to follow-up in third trimester, up to 9 months). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05329428, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 Mar 2026.