Vitamin D supplementation during pregnancy
Vitamin D is known to play an important role in bone metabolism through regulation of calcium and phosphate equilibrium. Vitamin D is produced by the body during exposure to sunlight, but is also found in oily fish, eggs and fortified food products.
Vitamin D deficiency is thought to be common among pregnant women in some populations, and has been found to be associated with an increased risk of pre-eclampsia, gestational diabetes mellitus, preterm birth, and other tissue-specific conditions.
Vitamin D supplementation during pregnancy improves maternal vitamin D status and may reduce the risk of pre-eclampsia, low birthweight and preterm birth. However, the evidence currently available to directly assess the benefits and harms of the use of vitamin D supplementation alone in pregnancy for improving maternal and infant health outcomes is limited.
Pregnant women should be encouraged to receive adequate nutrition, which is best achieved through consumption of a healthy balanced diet.
Vitamin D supplementation is not recommended for pregnant women to improve maternal and perinatal outcomes.*
* This recommendation supercedes the previous recommendation found in the WHO guideline ‘Vitamin D supplementation in pregnant women’ (2012).
Additional information for this recommendation can be found in the guidance summary and in the guideline, under 'WHO documents' below.
Systematic reviews used to develop the guidelines
Other related systematic reviews
Effect of vitamin D supplementation during pregnancy on maternal and neonatal outcomes: a systematic review and meta-analysis of randomized controlled trials
Vitamin D during pregnancy and maternal, neonatal and infant health outcomes: a systematic review and meta-analysis