Hypervitaminosis D

Hypervitaminosis D, also known as vitamin D toxicity or vitamin d overdose, is what happens when you have too much vitamin D in your body. Excess vitamin D causes calcium to build up in the blood – this is known as hypercalcemia.

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Impact of hypervitaminosis D on fertility

There currently isn’t enough data to determine how hypervitaminosis D may impact fertility. Studies on animals find that it can harm the maturation of the egg after fertilization and it is associated with higher rates of newborn death, but these results have not yet been replicated in human studies.

However, hypercalcemia is known to have harmful impacts on pregnancy and newborns. For instance, too much calcium can restrict the baby’s growth in the womb and lead to miscarriage. It can also lead to pregnancy complications including severe hypertension (high blood pressure), preeclampsia, pancreatitis (inflammation of the pancreas), and kidney stones. Babies born to hypercalcemic mothers have higher rates of newborn death, severe hypocalcemia (abnormally low amount of calcium in the blood), and mild hypercalcemia.

Potential causes of hypervitaminosis D

Vitamin D toxicity usually happens when someone takes very high doses of vitamin D supplements (over 10,000 IU per day) over a long period of time – it doesn’t normally come from too much sun exposure or a vitamin D-rich diet. Guidelines from the World Health Organization state that adults up to 50 years old should take 200 IU of vitamin D per day.

An oversupply of vitamin D can also be due to a malfunction in how the body metabolizes vitamin D or a health condition that makes the body produce an excess of an active form of vitamin D (such as Williams-Beuren syndrome).

Symptoms of hypervitaminosis D

Vitamin D toxicity and hypercalcemia can lead to the following symptoms, among others:

If it goes on for a while, it may cause kidney stones and bone pain.

Diagnosis of hypervitaminosis D

Hypervitaminosis D is diagnosed based on the results of various tests. Your healthcare provider may order the following tests:

• Blood tests that check vitamin D levels, calcium, and phosphorus
• Urine tests that look for excess calcium
• Bone X-rays to see if you have bone loss

Treatment to improve fertility

To get your vitamin D back to a healthy level and raise your chances of a successful pregnancy, you should stop taking vitamin D supplements and reduce your calcium intake. Your doctor may also prescribe intravenous fluids and medications including corticosteroids or bisphosphonates to restore balance to your vitamin levels, correct dehydration, and improve kidney function. Therapy with glucocorticoids decreases calcium levels in the blood.

Be sure to have your vitamin D and calcium levels checked before you get pregnant to avoid harmful effects on your baby.

This article has been verified by a medical professional

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