The Role of Vitamin D in Fertility and during Pregnancy and Lactation: A Review of Clinical Data

Int J Environ Res Public Health. 2018 Oct 12;15(10):2241. doi: 10.3390/ijerph15102241.


Vitamin D deficiency is common and there exists a huge gap between recommended dietary vitamin D intakes and the poor vitamin D supply in the general population. While vitamin D is important for musculoskeletal health, there are accumulating data suggesting that vitamin D may also be important for fertility, pregnancy outcomes and lactation. Significant changes in vitamin D metabolism during pregnancy such as increased production of the "active vitamin D hormone" calcitriol support the important role of vitamin D in this setting. Observational studies show that vitamin D deficiency is a risk marker for reduced fertility and various adverse pregnancy outcomes and is associated with a low vitamin D content of breast milk. Meta-analyses of randomized controlled trials (RCTs) document that physiological vitamin D supplementation during pregnancy is safe and improves vitamin D and calcium status, thereby protecting skeletal health. Although certain RCTs and/or meta-analyses reported some other beneficial effects, it is still not clear whether vitamin D supplementation improves fertility or decreases the risk of adverse pregnancy outcomes such as low birth weight, pre-eclampsia and neonatal mortality, or reduces wheeze/asthma in the infants. Nevertheless, vitamin D supplementation in pregnant women is frequently required to achieve a sufficient vitamin D status as recommended by nutritional vitamin D guidelines. In this review, we provide an overview of systematic reviews, meta-analyses and large trials reporting clinical data on the role of vitamin D for fertility, pregnancy and lactation.

Keywords: 25-hydroxyvitamin D; DBP; autism; brain; breast milk; gestational diabetes; pre-eclampsia; vitamin D; vitamin D binding protein.

Publication types

  • Review

MeSH terms

  • Female
  • Fertility / physiology*
  • Humans
  • Lactation / physiology*
  • Pregnancy / physiology*
  • Vitamin D / metabolism*


  • Vitamin D