Do I need to take extra Vitamin D while I’m pregnant?

Monica Freidline, RN, NP, CNM is a Certified Nurse Midwife.  Before becoming a Certified Nurse Midwife, Monica was a Registered Labor & Delivery Nurse for 15 years. She practices at Capital Women’s Care. 

The Importance of Vitamin D Supplementation During Pregnancy

Vitamin D – also known as the “sunshine vitamin” – yields many health benefits; it promotes bone health, boosts immunity, and even helps to prevent some forms of depression. A less commonly known fact is that Vitamin D also plays a role in promoting a healthy pregnancy. Both expectant and breastfeeding moms can positively impact their infants’ health by obtaining an adequate amount of Vitamin D.

Vitamin D deficiency during pregnancy

In a society where we spend much of our time inside, it is common to be deficient in Vitamin D. Vitamin D deficiency during pregnancy occurs frequently, but is completely preventable. While most nutrients in circulation increase during pregnancy, hemodilution may cause Vitamin D concentrations to decrease as early as 10 weeks gestation. Therefore, most pregnant women have low Vitamin D blood levels.

Adequate Vitamin D levels during pregnancy promote bone development in utero, and therapeutic levels often help moms feel more energetic. Boosting Vitamin D levels may also help curb some of the normally expected emotions such as pre-labor anxiety and postpartum blues. While the complete role of Vitamin D during pregnancy is still in the discovery phase, some small, limited studies correlate Vitamin D deficiency with low birth weight, preeclampsia, and gestational diabetes. Larger studies need to be completed to confirm these possible correlations.

Maternal & infant Vitamin D deficiency

Maternal Vitamin D deficiency is more likely to occur in the winter months and among those who use regularly use sunscreen, cover most of their skin, and/or have heavily pigmented skin. Moms who take a daily Vitamin D supplement while breastfeeding can help prevent infant deficiency. Breastfeeding alone, however, is not enough to prevent rickets (weak, soft bones in children). It is also important to discuss infant Vitamin D supplementation if you are breastfeeding. Most pediatricians recommend a daily Vitamin D supplement for all breastfed infants.

Vitamin D sources & supplementation

Although sunlight is the best source of Vitamin D, many women experience unprotected sun exposure due to heightened awareness of the risk of skin cancer.  Foods like fatty fish ( such as wild caught salmon) are a good natural food source of Vitamin D, but frequent fish consumption causes concern for elevated mercury intake during pregnancy.  In the United States, we are fortunate to have access to dairy foods which are fortified with Vitamin D.  However, consuming fortified foods alone will not reverse Vitamin D deficiency. The most measurable and accurate way to remedy a depleted Vitamin D level is with supplementation.

The recommended form of Vitamin D supplement during pregnancy is D3. This is the natural form of Vitamin D our bodies make from sunlight.

Daily prenatal vitamins containing Vitamin D may not be enough to treat a deficiency during pregnancy. Most sources state 2,000-4,000 IU per day is safe during pregnancy.

Talk to your provider about monitoring Vitamin D levels and developing a recommended daily amount based on your individual needs. Both you and your baby will benefit from it!