PREDIN: Pregnancy and Vitamin D Intervention Study

NCT05329428 | Completed

• 1 other identifier: 2021-03871
• Study Type: interventional
• Target: 105
• Locations: 1 country
• Sites: 1

Brief 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 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.

Conditions

Vitamin D Deficiency; Vitamin D3 Deficiency; Pregnancy Complications

Outcome Measures

Primary Outcomes (5)

• 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

  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

  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

  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

  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

  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

  At inclusion in first trimester of pregnancy

• Ferritin

  From inclusion in first trimester to follow-up in third trimester, up to 9 months

• Hemoglobin

  From inclusion in first trimester to follow-up in third trimester, up to 9 months

• Metabolomics

  From inclusion in first trimester to follow-up in third trimester, up to 9 months

• C-reactive protein

  From inclusion in first trimester to follow-up in third trimester, up to 9 months

Study Arms (3)

Vitamin D Supplementation 20 µg/day

EXPERIMENTAL

Dietary supplements containing 20 µg of vitamin D per day will be provided to study subjects.

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.

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.

Other: Usual Antenatal Care

Interventions

Vitamin D Supplementation 20 µg/day DIETARY_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 20 µg/day

Vitamin D Supplementation 40 µg/day DIETARY_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.

Vitamin D Supplementation 40 µg/day

Usual Antenatal Care OTHER

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.

Usual Antenatal Care

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• pregnant women in gestational week \<15

You may not qualify if:

• 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

Sponsors & Collaborators

• Göteborg University: lead
• Vastra Gotaland Region: collaborator

Study Sites (1)

Antenatal Care

Gothenburg, Sweden

Location

MeSH Terms

Conditions

Vitamin D Deficiency; Pregnancy Complications

Condition Hierarchy (Ancestors)

Avitaminosis; Deficiency Diseases; Malnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases

Study Officials

• Hanna Augustin, Ass Prof

  Göteborg University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, CARE PROVIDER
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 9, 2021
• First Posted: April 15, 2022
• Study Start: April 14, 2022
• Primary Completion: July 18, 2024
• Study Completion: September 16, 2024
• Last Updated: March 11, 2026

Record last verified: 2025-10

Data Sharing

• IPD Sharing: Will not share

Locations

SE (1)