How Vitamin D Boosts Fertility

How Vitamin D Boost Fertility

The Role of Vitamin D in the Body

Vitamin D is a fat-soluble vitamin that our bodies make when our skin is exposed to ultraviolet light from the sun. Our liver and kidneys also join in converting vitamin D into a usable form. If you live above the 45th parallel, like we do here in Portland, OR, you likely do not get sufficient sunlight to produce enough vitamin D year-round. Some other factors that influence how much vitamin D you can make include: air quality (air pollution can block UV light), skin color (darker skin tones need longer UV light exposure to produce the same amount of vitamin D), and age (older people have less of the precursor to vitamin D). 

We can also get vitamin D from the foods we eat, like egg yolks, salmon, tuna, beef liver, and fortified foods, or from supplements. It doesn’t seem to matter how we get the vitamin D; our bodies can utilize any of the forms. What is crucial is that we get enough of it. Some research shows that over 40% of the US population is deficient in vitamin D.

Vitamin D Boosts Fertility

Vitamin D is important for fertility because it regulates the expression of many genes in reproductive tissues. There are vitamin D receptors dispersed all over the reproductive system. For people who produce sperm, deficient vitamin D is correlated with low sperm count and motility. Vitamin D influences hormone production and supports healthy testosterone levels. 

For people who produce eggs, having enough vitamin D is associated with higher chances of conceiving and carrying a pregnancy to term. One group of people who are particularly susceptible to vitamin D deficiency are those with polycystic ovarian syndrome (PCOS). Vitamin D may play a part in regulating ovulation, insulin resistance, and androgen hormones, which are common issues in patients with PCOS. Other research shows that low vitamin D levels may play a role in the development endometriosis due to vitamin D’s anti-inflammatory properties.

Supplement Vitamin D to Avoid Poor Pregnancy Outcomes

Vitamin D deficiency during pregnancy is associated with poor outcomes: miscarriage, gestational diabetes, preeclampsia, early delivery, and postpartum depression. One study showed that supplementing with 4,000 IU of vitamin D daily had the best outcome for avoiding preterm birth and infections. Most prenatal multivitamins contain only 400 IU.

A simple blood test will tell you if your vitamin D levels are within the normal range. For fertility, many providers suggest that it is optimal to have vitamin D levels in the middle of the normal range rather than at either end. If you choose to take a supplement, consider taking a pill that includes vitamin K2, which is a cofactor for better absorption (though, talk to your primary care provider if you are taking blood thinners like Warfarin, because vitamin K impacts blood clotting). Other cofactors that help with vitamin D absorption are zinc, boron, vitamin A, and magnesium.

Outside of fertility, vitamin D is essential for strong bones, and it can reduce inflammation, lower insulin resistance, and help prevent infections. Insufficient vitamin D is linked to autoimmune disorders, cardiovascular disease, diabetes, and an increased risk for certain types of cancers. The best way to know if you need to supplement with vitamin D is to ask for a blood test.

If this blog piqued your interest, here is a wonderful resource with everything you might want to know about vitamin D and the human body:

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Established patients can schedule online, patients who haven’t seen us at Kwan Yin Healing Center call (503) 701-8766, or email us to schedule your appointment.

About Lisa Tongel

We are practitioners of Acupuncture and Chinese Medicine specializing in fertility, IVF support, pregnancy care, reproductive health, and pelvic pain.