Clinical trial NCT05329428: PREDIN: Pregnancy and Vitamin D Intervention Study
Official title: PREDIN: Pregnancy and Vitamin D Intervention Study - A Randomized Controlled Trial
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: NA
Conditions: Vitamin D Deficiency
Vitamin D3 Deficiency
Pregnancy Complications
Lead sponsor: Göteborg University
Sponsor class: OTHER
Collaborators: name: Vastra Gotaland Region
First posted: 2022-04-15
Enrollment: 102
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

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.

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.

Eligibility criteria: Inclusion Criteria:

* pregnant women in gestational week \<15

Exclusion Criteria:

* 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

Primary outcomes:
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
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: 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
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: 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
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: 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
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: 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
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
Secondary outcomes:
measure: Gene variant related to vitamin D metabolism
timeFrame: At inclusion in first trimester of pregnancy
measure: Ferritin
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: Hemoglobin
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: Metabolomics
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: C-reactive protein
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: Interleukines
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: Cytokines
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: Cortisol
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: Parathyroid hormone
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: Estrogen
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: Progesterone
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: Dietary intake
timeFrame: At inclusion in first trimester and at follow-up in third trimester, up to 9 months
measure: Body weight development
timeFrame: From inclusion in first trimester to follow-up in third trimester, up to 9 months
measure: Incidence of pregnancy-induced hypertension
timeFrame: Up to delivery
measure: Incidence of pre-eclampsia
timeFrame: Up to delivery
measure: Incidence of gestational diabetes
timeFrame: Up to delivery (up to 9 months)
measure: Incidence of preterm delivery
timeFrame: Up to 37 completed weeks
measure: Incidence of small for gestational age (SGA)
timeFrame: At delivery
measure: Incidence of large for gestational age (LGA)
timeFrame: At delivery
measure: Incidence of Intrauterine growth restriction (IUGR)
timeFrame: At delivery
measure: Apgar scores
timeFrame: At 1, 5 and 10 minutes after delivery
measure: Incidence of Caesarean sections
timeFrame: At delivery
measure: Incidence of miscarriage
timeFrame: During the first 21+6 weeks of pregnancy
measure: Incidence of Intrauterine fetal demise (IUFD)
timeFrame: Any time during pregnancy after pregnancy week 22+0 (up to 9 months)
Other outcomes:
Locations:
city: Gothenburg
country: Sweden
facility: Antenatal Care
Study officials:
affiliation: Göteborg University
name: Hanna Augustin, Ass Prof
role: PRINCIPAL_INVESTIGATOR
References: