e-Library of Evidence for Nutrition Actions (eLENA)

Iodine supplementation in pregnant and lactating women

Iodine is essential for healthy brain development in the fetus and young child. A woman’s iodine requirements increase substantially during pregnancy to ensure adequate supply to the fetus.

Most foods are relatively low in iodine content. To ensure that everyone has a sufficient intake of iodine, WHO and UNICEF recommend universal salt iodization as a global strategy. However, in certain countries salt iodization may not be feasible in all regions. Evidence suggests that in settings where universal salt iodization is not fully implemented, pregnant and lactating women and children under two years of age may not be receiving adequate amounts of iodized salt.

Depending on the percentage of households in a particular area with access to iodized salt, iodine supplementation may be necessary to ensure pregnant women are receiving adequate intake.

WHO recommendations

WHO and UNICEF recommend iodine supplementation for pregnant and lactating women in countries where less than 20% of households have access to iodized salt, until the salt iodization programme is scaled up.

Countries with a household access to iodized salt between 20 and 90% should make efforts to accelerate salt iodization or assess the feasibility of increasing iodine intake in the form of a supplement or iodine fortified foods by the most susceptible groups.


Additional information, including a suggested scheme for supplementation, can be found in the guidance summary, and in the guidance document under 'WHO documents' below.

WHO documents

WHO documents

GRC-approved guidelines

Status: not currently available

Other guidance documents


Related Cochrane reviews
Related systematic reviews
Clinical trials