Back to blog

Vitamin D and Pregnancy, Dr. Berger’s Corner: Health Topics from the Medical Director of CHA Fertility Center, Los Angeles

November 17, 2017

Dr. Berger’s Corner: Health Topics from the Medical Director of CHA Fertility Center, Los Angeles

Vitamin D and Pregnancy

There has been an enormous amount of publicity surrounding Vitamin D over the past couple of years. In pregnancy, the issues surrounding Vitamin D testing and replacement become critical because there are not one but two patients to consider. Despite the lack of clear guidelines, there is sufficient evidence to suggest that Vitamin D levels should be checked prior to and during pregnancy.
The growing baby needs Vitamin D, and those needs increase during the latter half of pregnancy, when bone growth and hardening are most prominent. Vitamin D travels to the baby by passive transfer, and the baby is entirely dependent on the mother’s own levels. Therefore, the levels in the mother are a direct reflection of the baby’s nutritional status.
Does My Prenatal Vitamin Have Enough Vitamin D?
The fact is, most prenatal vitamins do not provide enough Vitamin D. A recent study found women taking 4,000 IU of Vitamin D daily had the greatest benefits in preventing preterm labor/births and infections.

The same study confirmed that 4,000 IU of Vitamin D was not only safe for you, but for your baby, and the researchers from this study now recommend this daily dosage of Vitamin D for all pregnant women. The average prenatal vitamin only contains 400 IU of Vitamin D, so additional supplementation should be taken daily. But you should check the ingredients of your prenatal vitamin and check prior to adding more Vitamin D.

Why Do I Need Vitamin D During Pregnancy?
Vitamin D is beneficial for your own personal health. There is extensive research demonstrating the beneficial effects of Vitamin D for immune function, healthy cell division and bone health. Vitamin D is necessary for the absorption and metabolism of other nutrients, such as calcium and phosphorus. Many studies are finding a connection between low serum Vitamin D levels and an increased risk of certain types of cancers, autoimmune disease, neurological disease, insulin resistance, and cardiovascular disease. Deficiency with Vitamin D deficiency has also been linked to a severe pregnancy complication called preeclampsia.

What Contributes To Vitamin D Deficiency?
At this time, as much as 60% of the entire U.S. population is Vitamin D deficient. This includes pregnant women and women trying to conceive! There are many underlying factors related to this, and one of the most significant is the short list of foods that contain Vitamin D. These foods are egg yolk, salmon and cod liver oil, however, most Vitamin D is consumed through fortified foods like milk. For those suffering with lactose intolerance, fortified milk products are not a reliable source of Vitamin D consumption.

Additionally, many factors influence the body’s ability to make and absorb Vitamin D. These factors include: where you live, the season, how much time you spend outdoors without sunscreen, skin pigmentation, age, obesity, pollution, and having healthy intestines with optimal absorption capacity. These factors come in to play because Vitamin D is actually a hormone and needs sunlight in order for the body to manufacture it properly.

What Steps Can You Take To Get Vitamin D?
You can begin by making an effort to eat more Vitamin D containing foods. Next, research suggests sensible sun exposure (usually 5-10 min of exposure of the arms and legs or the hands, arms, and face, 2 or 3 times per week) can help as well. This means that there has to be at least some sun exposure without sunscreen/block!
However, the best way to really ensure adequate Vitamin D is through simple supplementation. When supplementing, your choices will be between two forms of Vitamin D. Ergocalciferol is the vegetarian form of Vitamin D and cholecalciferol is the animal-sourced form, usually derived from fish liver oil or lanolin from sheep.
The fish oil form is the most absorbable and utilized form for the body, but if you are vegan you should choose the one not derived from animal sources. Quality is important, so use a reputable brand when choosing your supplements.

Joshua J. Berger, MD, PhD, serves as the Medical Director of CHA Fertility Center in Los Angeles, California. Prior to his role as a fertility expert, Dr. Berger was a researcher involved with diet and obesity at UCLA who has trained athletes from around the world. He brings that unique knowledge to CHA in Los Angeles, California where elite athletes, actors/actresses and celebrities come for their care. Learn more at


CHA News, Health and Wellness, Pregnancy


 Get our CHA Fertility Newsletter

Mailing List Signup

  • Privacy Statement We respect your privacy and are committed to protecting it. CHA Fertility Center will not sell, license, transmit or disclose this information nor sell or rent your personal information to any third party outside of CHA Fertility Center/CHA Health Systems companies and associates.
  • This field is for validation purposes and should be left unchanged.