Vitamin D and Fertility

In my fertility acupuncture practice, I always incorporate nutrition, supplements, and lifestyle modifications into each patient’s overall treatment plan. I find that my patients get quicker and more lasting results when they are able to take a portion of the treatment plan into their own hands. One of the most common and most beneficial supplements I use with my fertility patients is vitamin D.

What Is Vitamin D?

Vitamin D is a bit of a misnomer since technically it is not really a vitamin. Because most mammals can synthesize adequate amounts when their skin is exposed to sufficient sunlight, vitamin D is considered a hormone. The most important forms of vitamin D in humans are vitamin D2 and vitamin D3. Both forms can be acquired either from the sun or the diet, and both forms must be converted in the liver and kidneys to a biologically active form for the body to use.

A person’s ability to produce vitamin D from sunlight depends upon their skin color and body weight. Individuals with darker skin have lower vitamin D production, and overweight individuals cannot produce as much of the vitamin compared to people of normal weight. 

For many people living in climates like the North America and other temperate or northern regions, it is almost impossible to synthesize enough Vitamin D. This is because we spend so much time indoors or, when we do venture outdoors, we’re mostly clothed or covered with sunscreen.

Vitamin D and Immunity

Vitamin D is a powerful antioxidant which both helps the body absorb calcium and plays a pivotal role in the immune system. In fact, several studies show a correlation between Vitamin D levels and the incidence of viral infections. The lower one’s levels of Vitamin D are, the more likely they are to suffer from upper respiratory infections. 

Fertility and Vitamin D

Aside from its affects on immunity, vitamin D plays a significant role in fertility. Studies have shown that vitamin D is linked to ovarian function, follicle growth, and ovarian reserve. There also seems to be a connection between vitamin D and ovulatory dysfunction related to PCOS. According to a study published in Fertility and Sterility in 2014, “vitamin D alters AMH signaling, FSH sensitivity, and progesterone production and release, indicating a possible physiologic role for vitamin D in ovarian follicular development and luteinization.” In other words, there is a strong evidence that vitamin D levels affect egg quality and ovulation.

Additionally, the active form of vitamin D, calcitriol, plays an important role in the production of estrogen. It also regulates many of the genes responsible for embryo implantation. The uterus and placenta produce calcitriol when a woman conceives, boosting the uterus’ ability to fight off infections while keeping the fetus intact. 

IVF Success Rates and Vitamin D

Perhaps even more significant, at least from an evidence-based perspective, is vitamin D’s role in IVF success. A study published in the Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM) showed that higher serum vitamin D levels translated to higher conception rates.

“Our work is the largest study to date to examine how vitamin D affects fertility in women who are undergoing IVF,” said one of the study’s authors, Alessio Paffoni, MSc. We found that women who had sufficient levels of vitamin D were more likely to produce high-quality embryos and more likely to become pregnant than women who were deficient in vitamin D.”

Women with adequate vitamin D levels, defined as above 20ng/ml, undergoing IVF were TWICE as likely to conceive as women with low vitamin D levels, defined as below 20ng/ml. There was about a 20% increase in pregnancy per each 10ng/ml rise in vitamin D, with the highest pregnancy rates in women with vitamin D levels around 50ng/ml.

How to Boost Vitamin D Levels

The best and easiest way to get vitamin D is through direct sunlight. In fact, 90% of our vitamin D typically comes from exposure to sunlight. Unfortunately, most Americans don’t spend enough time in the sun with enough skin exposed to synthesize adequate amounts necessary for optimal health and fertility. 

You can eat food rich in vitamin D but unless fish, like salmon, tuna, or mackerel, is a staple of your diet, it’s pretty unrealistic you will consume enough vitamin D via food. For instance, you would have to eat about a pound of salmon to get 3,000 iu of vitamin D. 

Finding a good vitamin D supplement is essential. Just about every one of my fertility patients is on a vitamin D supplement. I think I have only ever had 2 patients initially come to me with vitamin D levels at the 50ng/ml mark. Typically, the women I treat come in with levels well below 25ng/ml. 

Knowing how much to supplement is key. It’s virtually impossible to know how to dose vitamin D unless you run a blood test first. Ask your fertility acupuncturist, naturopath, or PCP to check your levels for you. It’s also helpful to run a 2nd test a month or 2 later to see how the serum levels have changed. You may need to start with a relatively high dose of vitamin D to get the levels up, but a long-term maintenance dose will have to be adjusted. 

Keep It Simple

When I work with fertility patients, I try to keep it simple where I can. Sometimes the most powerful things you can do to increase your chances of a successful pregnancy are really the easiest. I believe a daily supplement of vitamin D is one of the most important fertility boosters you can implement into your daily regimen.