Four reasons you should take vitamin D during pregnancy

As a pregnant mom-to-be, I am always thinking about what I am putting into my body. I take my prenatal vitamins every day and ensure that I fuel my baby with healthy foods and lots of water. This includes a regular intake of vitamin D, which is in addition to my prenatal vitamin. When I spoke with my doctor, she told me that the amount of vitamin D in my prenatal vitamins may not have the amount that is recommended by medical organizations, which ranges from 600 IU to 2000 IU per day.[1][2]

Now that spring has arrived, the sun will thankfully provide some natural warmth and vitamin D. However, studies show that obtaining enough vitamin D from the sun while pregnant just isn’t enough.[3] Therefore, here are my FOUR reasons for taking a vitamin D supplement throughout my pregnancy:

My bone and teeth health

There is also interest by scientists that vitamin D may play a role in reducing the risk of preeclampsion, a condition characterized by high blood pressure during pregnancy, therefore there are studies looking into this.[4][5] A vitamin D supplement is often advised by healthcare professionals to support a healthy pregnancy. I spoke to my physician about it. You should speak to yours as well.

The baby’s development

Baby’s bones are growing throughout the pregnancy and are directly affected by what I ingest. Vitamin D helps my baby develop strong bones and teeth and it is also considered a factor for overall good health. The baby’s need for calcium for its bone development peaks during the third trimester. It is important for me to ensure that I am getting adequate amounts of vitamin D to help increase my calcium levels throughout my entire pregnancy and especially during the last trimester because the baby will take from me what it needs, reducing my levels even further.[6] If my vitamin D levels are already low, this will reduce my vitamin D levels even more. I want to remain strong for my baby, so it’s important that I do all that I can to ensure the greatest health for my baby but to also take good care of myself at the same time.

Interestingly, it has also been shown that pregnant mothers with lower vitamin D levels had an increased risk of having a baby with low birth weight and shorter infant height.[7] By taking a vitamin D supplement, I’m making sure that my baby is staying as strong and healthy as I am.

The difficulty of natural absorption

Natural sources of vitamin D such as sunshine, fish, and red meat are often unable to give me adequate amounts of vitamin D. This is due to living in a colder climate, not spending enough time outdoors, and/or being a vegetarian. I also have celiac disease, which means that my intestines don’t absorb vitamin D efficiently. Taking a vitamin D supplement ensures that I get the right amount of vitamin D when natural absorption just isn’t enough.

Other benefits

With all the new hormones and changes in my body, it is important that I also keep my overall health in check. Does vitamin D play a role beyond bones and growth? The research is ongoing to understand the relationship between maternal vitamin D and the health of mom and baby. I checked with my doctor before taking vitamin D supplements and I recommend that you do too. Everyone, especially every mom-to-be, is different so it is important that you connect with a professional who will help you decide what works best for you and your baby. Questions about the best dose sometimes depend on factors such as diet, where you live, the color of your skin, and how much time you spend in direct sunlight.

This post was reviewed and updated in October 2019 

[1] Health Canada, Vitamin D and Calcium: Updated Dietary Reference Intakes, http://www.hc-sc.gc.ca/fn-an/nutrition/vitamin/vita-d-eng.php#a6
[2] Institute of Medicine, Dietary Reference Intakes for Calcium and Vitamin D, 2011
[3] National Institute of Arthritis and Musculoskeletal and Skin Diseases. Pregnancy, Breastfeeding and Bone Health. Last reviewed 2018-12.
[4] Mirzakhani H. et al. Early pregnancy vitamin D status and risk of preeclampsia. J Clin Invest. 2016 Dec 1;126(12):4702-4715.
[5] Carol L Wagner et al. Health Characteristics and Ouotcomes of Two Randomized Vitamin D Supplementation Trials during Pregnancy: A Combined Analysis. J Steroid Biohem Mol Biol. 2013 Jul; 136:313-320.
[6] National Institute of Arthritis and Musculoskeletal and Skin Diseases. Pregnancy, Breastfeeding and Bone Health. Last reviewed 2018-12.
[7] Mahboobeh Shakeri and Sima Jafarirad. The relationship between maternal vitamin D status during third trimester of pregnancy and maternal and neonatal outcomes: A longitudinal study. Int J Reprod Biomed. 2019 Jan;17(1):33-40.