Testing for Vitamin D deficiency: What it is and why it matters

Vitamin D Testing in Pregnancy

Vitamin D is a vital nutrient essential for your body and overall health, especially during pregnancy. However, many people aren’t maintaining optimal levels. Vitamin D3 (cholecalciferol) is a form of Vitamin D that plays a crucial role in calcium absorption, bone health, and immune function.

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The ‘sunshine vitamin’ 
your body needs

It’s known as the "sunshine vitamin" because the body produces it when exposed to sunlight. However, not everyone gets enough sun exposure, making Vitamin D3 deficiency common, especially amongst people in the U.K.

For those who don’t get too much sun, their dose of Vitamin D3 can be supplemented through nutrition. Vitamin D3 is found in:

Oily Fish: Such as salmon, mackerel, and sardines

Fortified Foods: Such as milk, cereals, and orange juice

Egg Yolks: Such as milk, cereals, and orange juice

Supplements : Vitamin D3 supplements are often needed to meet daily requirements, especially in pregnancy

  • Why a Vitamin D blood test is essential for accurate health insights during pregnancy

  • Gauging Vitamin D levels through food frequency questionnaires can be challenging because vitamin D intake depends on multiple factors beyond diet, such as sun exposure, skin type, and geographic location.

    Foods naturally rich in Vitamin D are limited, and fortified foods vary in their Vitamin D content. Without precise measurements, it’s difficult to determine whether you’re getting enough to meet your needs, especially during pregnancy when requirements increase.

    In an ideal world, a Vitamin D blood test—like the one included with NurtureKit®—provides a more accurate picture of your Vitamin D status, enabling you to take targeted steps to ensure optimal levels for you and your baby.

0-20ng/mL

Low levels of Vitamin D3 can lead to bone demineralisation, weak immune function, and a higher risk of pregnancy complications.

20-30ng/mL

These levels show improvement, but they are still considered suboptimal, particularly during pregnancy.

30-50ng/mL

This is the ideal range, supporting bone health, immune function, and reduced risks during pregnancy.

  • Optimal Vitamin D levels, it's all about your status

  • Vitamin D deficiency is common, especially in groups that have limited sun exposure or specific dietary restrictions. Those most at risk include individuals who live in northern latitudes, people with darker skin tones (as melanin reduces the skin’s ability to produce Vitamin D), and those who spend little time outdoors.

    Pregnant women are particularly vulnerable, as their bodies require higher levels of Vitamin D to support both maternal and fetal health. Other at-risk groups include older adults, people with malabsorption conditions (such as celiac or Crohn’s disease), individuals following a vegan diet, and those who are overweight, as body fat can impair Vitamin D absorption.
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BENEFITS

Vitamin D3 during pregnancy

Vitamin D3 is necessary for calcium and phosphorus absorption, which helps maintain strong bones and teeth. It also supports immune function and overall well-being, making it especially important for both maternal and fetal health. Research shows that sufficient Vitamin D3 levels can:

Support bone health

Vitamin D3 helps regulate calcium and phosphorus absorption, promoting healthy bone development for both mother and baby. (Holick et al., New England Journal of Medicine, 2007.)

Boost the immune system

Vitamin D3 enhances immune function and may reduce the risk of infections during pregnancy.
(Martineau et al., The Lancet, 2017.)

Help reduce the risk of pre-eclampsia

Higher Vitamin D3 levels are linked to a lower risk of pre-eclampsia, a serious pregnancy complication characterised by high blood pressure. (Bodnar et al., Journal of Clinical Endocrinology & Metabolism, 2014.)

Improved birth weight

Vitamin D3 deficiency has been associated with lower birth weights. Maintaining optimal levels supports healthy fetal growth. (Merewood et al., Pediatrics, 2009)

Support maternal mental health

Adequate Vitamin D3 levels can help reduce stress and lower the risk of postpartum depression.
(Groves et al., Journal of Steroid Biochemistry and Molecular Biology, 2013.)

Support your Vitamin D with Nurture®

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