Does Vitamin D Help You Get Pregnant?
Vitamin D deficiency has been linked to infertility and Vitamin D supplements have, in recent studies, shown to improve fertility. Dr Miller discusses the results of the largest Vitamin D and fertility study to date.
There's been a lot of interest lately about Vitamin D and fertility.
What is Vitamin D?
Let me give you a little background about vitamin D. Vitamin D is an oil soluble vitamin that has several important functions in the body. It helps to absorb dietary calcium and phosphorus from the intestines.
Vitamin D keeps the calcium and phosphate levels in the blood normal, thereby promoting bone health.
There are two main ways in which you get vitamin D in your body. Most of the vitamin D in humans is made in the skin when exposed to sunlight. The amount of sunlight needed to synthesize adequate amounts of vitamin D varies depending on the person's age, skin color, sun exposure and underlying medical problems.
The production of vitamin D from the skin decreases with age. In addition, people who have darker skin need more sun exposure to produce adequate amounts of vitamin D, especially during the winter months.
Vitamin D from the diet
Another important source of vitamin D are foods like sardines, salmon, eggs and liver.
However, in humans, less than 20% of vitamin D is obtained from the diet. In the United States, commercially fortified cow's milk is the largest source of dietary vitamin D.
The big risk is inadequate exposure to the sun. This is especially a problem in the winter, when you don't go outside as much and when you do you're generally covered up.
How can you tell if your vitamin D level is low?
It's pretty easy actually. A blood test from your doctor will tell you what your current vitamin D level is.
Do people with vitamin D deficiency have more problems with infertility?
Some studies have found that vitamin D deficiency is more common in fertility problems like polycystic ovary syndrome and uterine fibroids. Other studies have found that supplementing women with vitamin D improved the success of treatments ranging from Clomid to IVF.
One of the limitations of these studies is that they involved relatively small numbers of women.
Groundbreaking vitamin D study
It turns out that until 1985, adding vitamin D to margarine was required in the entire country of Denmark. Then, the requirement abruptly stopped.
Denmark also keeps registries of how many people are being treated for fertility problems and how many gave birth.
Recently, researchers used that change in vitamin D requirements to investigate the impact of vitamin D supplementation on women with infertility.
They looked at three groups:
- 1 - Women diagnosed with infertility during supplementation period
The vitamin D exposed group - this included over 6000 women who had their primary infertility diagnosis made between 1980 and 1985 when vitamin D fortification stopped.
- 2 - Women diagnosed with infertility right after supplementation stopped
A group of 1400 women who were diagnosed with infertility within 15 months after fortification stopped
- 3 - Women diagnosed with infertility a long time after supplementation stopped
A group of 8,500 women who were diagnosed with infertility more than 16 months after fortification was stopped.
The results were really interesting. Women in Group 1 (the vitamin D group) had an 87% higher chance of live birth compared to group 3 (the no vitamin D group).
Women in group 2, (who were diagnosed right after fortification stopped) were 52% more likely to have a live birth compared to the no supplement group.
One other interesting thing about this study: the benefits of vitamin D supplementation were just as strong in the dark winter months as in the sunnier summer months - which is a little strange since you might guess that more people would benefit in the winter.
Our bottom line: It seems pretty reasonable if you have infertility to check your vitamin D levels and get your levels into the normal range if they're low. Even if your levels are normal, take a prescription prenatal vitamin containing vitamin D.
We suggest that you take a look at green teas to boost your fertility. They are rich in Vitamin D, which is what you should be looking for to increase your chances of getting pregnant.