Vitamin D in Pregnancy

  • days left to enroll
  • participants needed
  • sponsor
    University of Aarhus
Updated on 6 May 2021


Danish pregnant women are recommended ad daily vitamin D supplement of 10 g. Despite the fact that 9 out of 10 women take vitamin D supplements, more than 40% of pregnant women are vitamin D deficient, putting them at an increased risk of pregnancy complications like fetal growth restriction and pre-eclampsia. Our hypothesis is that pregnant women would benefit from an increased intake og vitamin D and that an intake of 90g/day can reduce the prevalence of placenta-related pregnancy complications. Combining a double-blinded randomized trial (10g vs.90g) with collection of placental material, we want to test if the prevalence of pregnancy complications is reduced and explore how vitamin D affects placenta to improve our understanding of the disease pathology and risk factors.


As vitamin D (vit-D) is essential for growth and linked to placental function, health authorities recommend a daily 10g vit-D supplement in pregnancy. Despite the fact that 9 out of 10 women take supplements, more than 40% of pregnant women are vit-D deficient, putting them at an increased risk of pregnancy complications like fetal growth restriction and pre-eclampsia. These conditions affect 6-10 % of all pregnancies, increasing the risk of preterm delivery, perinatal morbidity and mortality. In worse case, preeclampsia may also be fatal for the pregnant women herself. Around 20% of vit-D intake comes from the diet (e.g. fish, egg yolk) and the rest from sun-exposure. However, in Denmark, there is not enough sunlight from October to March to fuel vit-D synthesis underlining the need for supplementation. The high prevalence of vit-D deficiency indicates that current guidelines are not sufficient. Indeed, todays recommendations date back to a small-scale 1986 Norwegian study not taking into account dietary differences such as the high intake of fish in Norway. Since then, accumulating evidence has linked exposure to pregnancy complications and vit-D deficiency per see to long-term health problems in the affected children. This include a higher risk of asthma, cardiovascular disease, diabetes, obesity schizophrenia, neurodevelopmental problems and multiple sclerosis. Notably, the affected women also suffer an increased risk of disease, e.g. heart disease in later life. Vitamin D supplements in the range of 90-100 g are safe in pregnancy, but it is not yet known if and to what extent increased vitamin D supplementation prevents pregnancy-related diseases. Combining clinical testing of 90 g vitamin D supplements, with identification of which placental pathways that are affected by vit-D would considerably improve our understanding of disease pathophysiology and the role of vit-D and improve the health of future generations in an easily implementable way.

Condition Gestational Diabetes, Diabetes Mellitus, Diabetes Mellitus Types I and II, Diabetes Prevention, Diabetes (Pediatric), Vitamin D Deficiency, Intrauterine Growth Retardation, Pre-Eclampsia, Preeclampsia, Vitamin Deficiency, Vitamin Deficiency, Pregnancy Complications, Pregnancy Complications, Diabetes Prevention, Diabetes Mellitus Types I and II, Diabetes (Pediatric), Preeclampsia, iugr, fetal growth restriction, fetal growth retardation, intrauterine growth restriction, toxemia of pregnancy
Treatment Vitamin D3 (90µg), Vitamin D3 (10µg)
Clinical Study IdentifierNCT04291313
SponsorUniversity of Aarhus
Last Modified on6 May 2021


Yes No Not Sure

Inclusion Criteria

All pregnant women attending the nuchal translucency scan in week 11-13 of gestation as part of the national prenatal screening program

Exclusion Criteria

Age< 18 years
Women with calcium metabolism disorders
Women who gets doctor prescribed vitamin D treatment
Women with chronic kidney disease
Clear my responses

How to participate?

Step 1 Connect with a study center
What happens next?
  • You can expect the study team to contact you via email or phone in the next few days.
  • Sign up as volunteer  to help accelerate the development of new treatments and to get notified about similar trials.

You are contacting

Investigator Avatar

Primary Contact


Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.

Learn more

If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.

Learn more

Complete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.

Learn more

Similar trials to consider


Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note