Impact of vitamin D deficiency on fertility
Vitamin D deficiency may lead to menstrual cycle disorders and interfere with ovulation. It’s also associated with polycystic ovary syndrome and low levels of AMH, which decreases the egg reserve.
Research has found that women with healthy levels of vitamin D get pregnant quicker with IVF and are more likely to have a live birth. And studies of women struggling to conceive have found that up to half had a vitamin D deficiency.
Furthermore, vitamin D deficiency can increase the risk of developing high blood pressure during pregnancy (preeclampsia) which can have serious health complications for both the mother and baby. Low levels of vitamin D in men has also been linked to poor semen quality.
Potential causes of vitamin D deficiency
Not getting enough vitamin D through your diet or from the sun is the main cause of a deficiency. It’s also possible that your body isn’t absorbing vitamin D as it should. Certain health conditions (kidney and liver diseases and cystic fibrosis), medications, obesity, or weight loss-surgeries are other potential causes of a deficiency.
People with darker skin and those who cover their skin when spending time outside are at greater risk of developing a vitamin D deficiency.
Symptoms of vitamin D deficiency
Signs of a vitamin D deficiency include:
- Fatigue
- Bone pain
- Weak, achy and crampy muscles
- Depression
Diagnosis of vitamin D deficiency
Your body produces 25-hydroxyvitamin D (also known as 25(OH)D) when you get vitamin D from foods and sunlight. Low levels of this in a blood test mean you have a deficiency.
Treatment of vitamin D deficiency to improve fertility
The World Health Organization recommends exposing your arms and face to the sun for 30 minutes per day to get your fill of vitamin D. But in some regions, it’s hard to do this year-round.
Luckily, it’s easy to treat vitamin D deficiency by taking dietary supplements. Children and adults up to age 50 (including pregnant and lactating women) are recommended to get 200 IU of vitamin D per day. Speak to your doctor about choosing the right dose for your vitamin D supplement. Be careful not to overdo it with the supplements, as too much vitamin D can have health complications.
You can also increase your intake by eating more foods with vitamin D, such as:
- Mushrooms
- Fatty fish (salmon, tuna, mackerel and sardines)
- Beef liver
- Egg yolks
- Cheese
Foods fortified with vitamin D include:
- Milk products (cow’s milk, soy, almond and oat milk)
- Cereals
- Fat spreads
- Meat products
If vitamin D has been added to a food, you should be able to see it on the label.
For more nutritional advice during your TTC journey, check out our article on fertility foods for women.
- Most info came from the current LEVY article on vitamin D.
- Vitamin D Deficiency. Cleveland Clinic. Accessed 12 September 2022.
- Singh V, M.D. et al.: Association between serum 25-hydroxy vitamin D level and menstrual cycle length and regularity: A cross-sectional observational study. Int J Reprod Biomed. 2021;19(11):979-986.
- Łagowska K: The Relationship between Vitamin D Status and the Menstrual Cycle in Young Women: A Preliminary Study. Nutrients. 2018;10(11):1729.

